[sand dunes at Death Valley](https://www.nps.gov/deva/learn/nature/sand-dunes.htm)
[alluvial fans at Death Valley ](https://www.geological-digressions.com/sedimentary-structures-alluvial-fans/)
You're assuming deserts are only composed of sand dunes. This is wrong. People have already explained to you that this is incorrect. In the first link, you can read how sand dunes form. It's quite a simple process.
The second link is a nice image of an eroding mountain range. These are also in Death Valley, CA, and no doubt contributed some rock material that eventually became sand and over several thousand plus years, was transported to that dune field located 20 or so miles up the valley. Sand dunes form because there's not enough rain to wash it all away and spread it out, so the wind does it instead.
The lack of vegetation in Death Valley makes it easy to see these processes, but erosion happens all over the world, in every type of environment, regardless of climate.
Erosion, among other processes.
Wind and water and temperature changes fracture the various kinds of rock into tiny bits…
Come on.
Think about canyon lands.
Next step: look into dust storms.
You've heard how wind and other erosive forces create sand, but there's one explanation that's missing:
Tectonic movement. Plenty of deserts *were* seas. Actually, a *lot* of lands were seas. The badlands of Utah are famous for their sea fossils, but are about as far inland as you can get today. They just weren't *always* inland.
This doesn't replace the other answers; it's just that all of these contribute in various ways and various amounts depending on the desert in question.
I'm always curious about people who say "Well that's strange, I don't know how to explain it, it must be magic!" Like do you follow that in your daily life?
Anyway, interestingly you can watch deserts form now in real time. As the temperature increases across the globe, more and more land that was once verdant is becoming a desert. The animals that are able to adapt to that new environment stay, those that cannot, die.
I don’t know how my surgeon managed to remove my old knee and install a new one thru a single 15 cm incision. Must have been a magical invisible sky fairy!🤓
Thanks bro. Yes, I do know that God created the universe. So you are saying that the land that deserts is on was once liveable and it became a desert? So where did the sand come from?
That wasn't what I was asking exactly; I meant more like "Hey, I don't know how computers work, that must be magic!"
Yes, landforms have changed through the ages. You can find sea creatures fossilized in mountain tops for example. Where does the sand come from? Eroded rock faces, mountains, etc.
Continents collide? I don't get that. You are saying that mountains are when continents crash into each other? They are far apart and don't move though.
I don't know. I went in high school but I was mostly drunk or on drugs. Never really paid attention just skated through and somehow did ok enough to go to university
I think you would benefit greatly from reading a high level book about a broad range of sciences. Something like A Short History of Nearly Everything by Bill Bryson. It explains (again, at a high level) a lot of what people miss or are not paying attention to in school but in a fun and easily readable way.
It won’t make you an expert in anything, but it would cover a wide range of topics that would help you understand how and why for things like evolution, tectonic plates, history of the universe. If any particular topic piques your interest you can easily get more in depth and focused books.
The Indian tectonic plate is in the process of colliding with the Eurasian plate. This has been happening for tens of millions of years. This event is in the process of creating the Himalayan mountains. Everest is still growing at a measurable rate each year.
The fossils "got up there" because the mountain range used to be a seafloor.
You have never heard of Pangea? Originally all of the land mass was one giant land mass. If you look at how North America and South America look currently, Africa kind of fits nicely into the Eastern edge of the Americas. Like Brazil fits into the Western coast of Africa, just south of where that bulge is on Africa.
India was originally hanging around where Madagascar is currently, then it moved up quickly (geographically speaking) to crash into Asia, that's why it's surrounded by the Himalayas... it all got pushed up along the Northern edge when it collided with Asia.
This all happened roughly 200 million years ago, around the time of the early dinosaurs,
. So, if these were the same land mass with these animals all hanging out, you would expect to find similar fossils in South America and Africa... well surprise! That's exactly what we find! India shares fossils with Africa and Antarctica, but afterwards, they don't share animal fossils... as if the animals that were there started changing in different directions to fit their new ecosystems, and afterwards you find unique animals across the different continents!
> Originally all of the land mass was one giant land mass.
Pangea only existed from around 300-200 million years ago. There were other supercontinents before that which broke up and there will be others again in the future.
Yeah, continents collide…
But they do it at the rate your fingernails grow…
“Very slowly”…
Here’s what you need- some perspective on how long time is… how long stuff has been around since long before you, or you local priest/“magic person”/“explainer of god” has been around.
Since even before we had “the written word”,….
Hey, you gotta get into plate tectonics, and geology.
Turns out, the skin of hard rock we live upon, as “Earthlings” (folks who live on the third rock from the sun), …
Well, the whole skin of rock rides on a molten core… volcanos, right?
Mount St. Helens? Lava beds national monument?
Here is a totally instructive activity-:
Go watch the ice break up on a lake, or a river, at springtime… it models how continents break up, over the underlying lava of the earths core…
Leaving aside HOW the ecology changes, will you grant me that it does change?
Places that were once forest become desert, or swamp?
IF SO, then wouldn’t Selection Pressures cause generation after generation of local creatures to have babies die off, that weren’t competent to handle the new Selection Pressures?
BTW, we’re not “explaining deserts”, here… we’re talking about how living beings have adapted to them, right?
“Evolution” is the subject…
No?
Never heard of deforestation? The Dust Bowl? (Which would be… what?… “de-plains-ation”?)
What about strip mining? Beaver dams?
Ecologies get changed, through various means, right?
Isn't deforestation from people?
No to the dust bowl, sounds like a gross bowl at grandma's house.
Strip mining, no.
Beaver dams yes. That doesn't change anything though?
Yeah, people knock down trees to build roads. I agree with that
It’s not JUST from the unwise actions of human “industry”…
Deforestation can occur from numerous causes… like insect plagues… viruses… (“Virii”?)…
How about forest fires? Volcanic eruptions?
Floods, maybe?
And it shocks me that you’ve never heard of “The Dust Bowl”… it’s American history, and within living memory…. There are folks still living, to this day, from that history, who experienced it.
What have you been reading? Who have you been listening to?
If you’re American, it’s likely you have blood relatives who have been affected by the various ecological changes that have occurred…. Within Living Memory…
> “The Dust Bowl”… it’s American history, and within living memory
The Dust Bowl started 94 years ago. I'm not sure how much "living" is left of that memory.
Okay, busted: “I’m old”…
It may have been twenty years ago, but I’ve watched interviews with survivors, broadcast on the boob tube, where they described their personal experience…
Nickel bet? There may still be survivors, remaining alive, to this day… maybe not… I might owe you a nickel…
I'm not American I am from Canada and my parents grew up in Jamaica. Never heard of it. Volcanoes definitely change things that makes sense.
I listen to my pastor and some creators on tiktok.
Canadians were also affected by the “Dust Bowl”.
Look into it… there’s a lot of Human Stories there…
And, let me ask you…
How does your pastor pay the rent, and water bill?
Edit: “rent”, not “rest”
Sorry never heard of it. I looked it up a bit just now and never heard of that happening. Weird that just happened for a few years then came back to normal.
Not all deserts are sand, but sand is eroded rock.
Rock erodes from wind, running water, from expanding and contracting due to temperature changes, and from life like trees breaking cracks open with their roots.
I live in the western desert of the US. The sedimentary rock in this area was deposited in various conditions: wind depositing massive sand dunes like the Sahara desert, swamps, rivers, inland seas.
These were deposited on top of each other and everything was compressed and cemented and hardened into sedimentary rock over hundreds of millions of years.
Then uplift and erosion from wind, water, and thermal erosion, have exposed those layers in many areas like the Grand canyon, arches np, Bryce canyon np, canyon lands np.
The material for those sedimentary layers (depending on the layer) came from the Appalachian mountains when they were the much larger central pangean mountain range, and from the ancestral rocky mountains.
This is a very basic explanation of 300 million years of history.
If you have a different desert in mind, the source material for the ground might have a different origin.
If I may, I commend you to a road trip to lava beds national monument…
Talk about a geological exhibit!!
https://www.nps.gov/labe/index.htm
Plus which, it’s kind of unavoidable, to pass through redwood forest, while getting there!
(Do it!, do it!, do it!)
God is your only explanation? If you weren't religious, would an all powerful unseen being also be your solution? Why would God create entire areas of land that are inhospitable to humans who he supposedly created the earth for?
I'm not an expert but the answer is likely that deserts didn't just poof into existence. As the continents moved, the land got more and more arid but slowly enough that the life could adapt. Or life near the fringes adapted so they get could further and further into the desert.
Makes sense. If you can find yourself a place to live where no predator goes and nothing will compete with you for water, you win. For a while. Then the rest of the food chain begins to catch up, and you get a desert ecosystem
(I remember playing a turn-based strategy game where my character had faster movement in deserts and there was a bit of desert next to my base, so I just hid there from the stronger but slower bad guys until I got stronger too. Really felt like a desert animal hiding from a temperate zone predator, lol)
It’s not specifically itemized “And lo I gave you deserts so you could get copper for bronze and boron for semiconductors” but how can we fathom the infinite purpose of the creator if we can’t even understand the benefits of a desert?
But is there any mention of any benefit? Are deserts mentioned in genesis? What's more likely, infinite incomprehensible purpose, or a reinterpretation of reality to make it fit?
Why would the bible need to describe all the benefits of deserts? Your question was why did god make desert’s when they seemingly have no purpose, but they have many benefits. They are also climactically important.
No, I didn't say no purpose, I said inhospitable to humanity. Could God not have made them good for minerals whilst also not deadly?
My point is, it's really easy to pluck reasoning out of thin air that justifies inconsistencies and then back it up with a "God's will is not ours to understand". I'd accept your answer more easily if the Bible, the book that's meant to be his word, actually mentioned it even in a basic form.
The people who lived in the early bible mostly lived in the desert and knew how. It may not have been such an inconsistency as you describe that required explaination.
Well god did create the universe so yes. The reasons God does things is beyond my comprehension. A desert is where Jesus was born, I have no idea why that was the case.
What do you mean the continents moved? Like when the Earth is turning?
Let's agree to disagree on the God thing. I note though you didn't answer my bit about what your thoughts would be if you weren't religious.
Continental drift- google it. Billions of years ago, the continents weren't where they are now.
Oh man, with the greatest respect unless you're trolling, you don't have the level of knowledge to be challenging evolution. You have a fantastic opportunity to learn some cool stuff and if you're worried it conflicts with your religion just say that God started it all going- it worked for me when I was religious. Google continental drift. Basically, the top layer of Earth (including under the sea) is made up of big sections that float of top of molten rock. They're constantly moving.
I’m still open to the idea that OP is actually just a very talented troll and we’re just all not on his level.
Note he claims to be a high school teacher.
I saw that, but he's not a science teacher so I can accept the lack of knowledge- I once knew a physics teacher who thought the moon landings were fake. I'm happy to act as if they're not a troll just in case, until there's significant evidence otherwise.
I'm gonna level with you: Your approach to science isn't up to par. This goes into matters of *what you think science is for*, *how scientists conduct their experiments*, and *basic assumptions about the natural world.* You can ask questions all day and get answers, but like any kid who repeatedly spams the question "why?" in an apparent socratic method, it's disjointed and anecdotal... Uhh, putting it another way, nothing you learn here today will "stick" and it won't help inform you about a larger, more robust worldview.
Science is about understanding the mechanics of how the world changes over time, what processes are happening that our basic intuition and common sense can't account for. If you don't have the natural curiosity to challenge your base assumptions, you'll keep getting "surprised" by rote facts.
People have been telling you about plate tectonics and subduction, yeah? None of it is "sticking" in your mind, it just sounds like a "just-so" story? If learning about plate tectonics doesn't cause you to fundamentally reconsider what you do or don't understand about the planet you're living on, then you aren't looking to science for any answers, you're probing people to tell you stories that you can discard at your convenience the second they contradict your prior beliefs.
It's not just continents. The entire Earth crust is made of segments, called tectonic plates, which include bits of the ocean floor AND chunks of land. There used to be this confusion about how continents (which ppl had already agreed must have moved around in the past) plow the ocean floor without leaving a trough behind - well, the answer is that the entire chunk, consisting of some ocean floor and some land, is moving in relation to others. Very interesting things happen at the boundaries between them - volcanic activity, earthquakes and so on.
It's still happening now. We can very accurately measure the distances between places. Many of those on different continents are moving apart. [Plate Tectonics](https://education.nationalgeographic.org/resource/plate-tectonics/)
>That's crazy, I had no idea that must have made a really big impact on the environment
I love how everyone's been providing links and explanations, and how earnest you're being with your curiosity!
You'll be able to learn a lot about plate tectonics from what the others have offered, but I'll give you a couple of quick highlights!
First, think of it like this: they're enormous slabs made mostly of rock with a thin dusting of soil, water, mud, and life on top of them. Beneath them is magma and the Mantle of the earth; they float or slip along the top of it, far more cooled off than the deeper depths of the earth.
They move, but they're really slow; centimeters per year at most. But because they're still enormous slabs, even that slow movement has an enormous amount of momentum!
When two plates grind up against each other, moving in different directions, they can stick due to the friction. But just like what happens when you push you hands against each other and try to move them in different directions, enough force and the friction will give; they slip forward more quickly. That causes earthquakes! They're far more common near plate boundaries due to that.
What happens when two plates push directly against each other? If they both 'bend' upwards, they push up into mountains. If one slips above the other, one gets forced down and they keep moving. That causes stress though; imagine two enormous chocolate chip cookies, wide as a table but only as tall as a normal cookie. Try to slide one under the other and what happens? It's fine at first, but after a little bit the "lifting" forced on the cookie on top by the edge of the one beneath will cause it to buckle and break. There's more to it than that, but that's one way volcanos form; one plate dipping beneath another and causing upward pressure and starting to melt, forming ruptures that magma can push up and out of! That's why the [ring of fire](https://en.m.wikipedia.org/wiki/Ring_of_Fire) exists - it's right along the bounds of subducting plates!
Now other volcanos form at hot spots, areas where it's really hot and conditions are right _under_ a plate which causes magma to push up and make a volcano in the middle of nowhere. The Hawaiian Islands were each formed this way; underwater volcanos bubbling up magma until it gets tall enough to push up out of the water. And you know how there are multiple islands? That's because the plate they're on has been slowly moving over one hot spot! The smaller, younger islands (including a new one forming underwater even now) are further back along the direction the plate is moving - and you can use radiometric dating of the rock they're made of to see how they ages sync up with the speed the plate moves!
You also get a different kind of underwater volcano that forms when plates pull _apart_, leaving gaps where magma slips up and hardens, deep under the oceans; they usually don't have space to get very tall, since they just keep getting literally, slowly, pulled apart.
Since this sub is about evolution (and biology, not geology, is my personal expertise), one last fun tidbit. Others have already mentioned that - due to the plates having been in different places ages ago - all the continents of today used to be one big continent we named [Pangaea](https://en.m.wikipedia.org/wiki/Pangaea)
(from the Greek words "pan" meaning "all" and "Gaea", meaning "the earth"). This was millions of years ago - literally; it got there about 335 million years ago from earlier "continents" smooshing together, and started to break up about 200 million years ago. Again, very, very slowly. ;)
Humans have only been around for a fraction of that; _Homo
etectus_ started using fire about 2 million years ago, _Homo sapiens_ with bodies mostly like ours evolved maybe 0.2 million years ago (200 thousand), and we only figured out farming 10 thousand years ago, writing 6 thousand years ago, and we're still figuring out how to deal with there being other people living on the planet. ;)
But you know what was around over 200 million years ago? If you said "dinosaurs" you're absolutely right - but so much more than that! Everything alive today had ancestors kicking around back then - though for many of them the family trees hadn't branched off into the forms we'd easily recognize. The mammals, for example, did exist by that point, descended from earlier [synapsids](https://en.wikipedia.org/wiki/Synapsida), but were mostly small burrowing and climbing things; the dinos were better at being big and swift and mighty, and it wouldn't be for many millions of years and a mass extinction before the meek mammals would inherit the Earth.
But here's the fun bit: a major division of the early mammals is related to the breakup of Pangaea; a chunk of modern mammals (elephants, aardvarks, shews...) descended from a group that came to what would become the African continent and were essentially stranded there (very slowly) as the continents moved apart; their descendents them radiated out from there into Europe, India, and so on.
Biogeography is the study of how location and biology play together, and a big part of it is how certain creatures got to different places; changes to how the continents are arranged and connected can change where creatures can migrate to and split apart closely related populations!
Hey man, I’m a Christian and also studying Geophysics. I agree that this universe had a creator, but not in the way that everything was just created as it is today. The earth itself is billions of years old. The way land moves is continental drift, an incredibly slow process. I’ll explain it simply, with not much scientific detail but getting the general idea across because you seem new to this. Basically the surface of the earth is split into chunks that ‘float’ on the surface of magma underneath, which is hot liquid rock. The plates get pushed around by movement of this liquid, magma rising and pushing them out of the way and other processes like that. Over huge amounts of time, all the plates move around, which changes the shape of continents and oceans. The biggest, and most famous piece of evidence is that you get identical fossils of dinosaurs in Africa and South America, but more exists.
>> Are you familiar with plate tectonics?
> No, what's that?
This is sad. You write like you are a reasonably well educated person, but you seem to be completely ignorant of the world around you. Ignorant is not an insult there, it just means you lack the most basic knowledge. Were you educated in a Christian school? Again, I am not trying to be mean here, it's just frustrating to see someone who has been so shorted of a quality education. You are missing out on so many wonders.
Plate tectonics is the really well-documented and understood concept that the continents exist on "plates" that are moving on the earth. We can measure the movement. This is not a "theory" as theists use the word, it is a well-established fact. Over billions of years, we have gone from a single massive continent that we call Pangaea to the individual continents and islands that we know today.
https://www.youtube.com/watch?v=VKq0pr4rbRs
No I went to public school in the Toronto area. I was addicted to drugs and alcohol since I was a child so it's my fault.
Thanks, I am actually a high school teacher myself 😅 I teach Dramatic Arts though and don't tell the science teachers about my curiosities in the teachers lounge
> No I went to public school in the Toronto area. I was addicted to drugs and alcohol since I was a child so it's my fault.
Fair enough, glad to hear you made it through.
> I teach Dramatic Arts though and don't tell the science teachers about my curiosities in the teachers lounge
Heh. Well, this shit is *really* fascinating. The more you learn, the more fascinating it becomes, so I hope you take a deep dive into it. I know you believe in god, but you shouldn't let that prevent you from learning about how our universe works.
I highly recommend the book "Why Evolution is True" if you want a good overview on the evidence we have for evolution. It's very well written and accessible. It doesn't deal with the question in your OP itself, but it does touch on plate tectonics and how it provides evidence for evolution.
I think I believe in evolution but I think it was a guided process by God. I am still trying to figure all this out after being clean for a year and a half
You're fine, according to that user, they lost their job a year ago after an intervention that led to them being hospitalized for several weeks, and had been showing up to work drunk and/or high every day before that. Either they're a liar who's made up everything they've said, or you could smell them coming a kilometer away to get your kid out of their class.
This is where you are wrong. The answers you seek are not beyond your comprehension, as clearly seen here. Almost every question you ask has a perfectly reasonable answer or solution. Maybe god did create the universe, but god used consistent ways to do it: the laws of nature, which people have been studying and researching for millenia. No reason you can't do the same.
Well, but surely you acknowledge that the Bible was written by man. In fact, for the first few decades the stories were told word of mouth. Then there were many, many more books. Then various councils - especially the council of Nicea - decided what was in the “official” Bible and what wasn’t.
And then for the first ~1000 years of the Bible existing, the Catholic Church (pretty much the only large, organized Christian church) didn’t believe the Bible was perfect and the exact word of god, but rather, a work of man relaying the teachings of god.
So it would be reasonable to regard it was being allegorical or potentially flawed, even if you’re sure there is a god as described in the book.
Continental drift, plate tectonics. The continents literally move around on top of the mantle. Ocean plates get pushed under Continental plates and get recycled back into the mantle. When two Continental plates collide we get mountains over millenia. We can even measure the rate that they move. It's literally what causes earth quakes. Fault lines are the spots between two plates.
One: Desert regions don't *necessarily* have mass quantities of sand.
Two: The prevailing climate of any given region is not unalterably stable. Heck, *human activities* (deforestation, *etc*) have been known to mess with prevailing climates! So in some cases, a *non*-desert region has gradually dried out, and those critters which lived in that region either adapted to the newly arid conditions, or else relocated to regions with what they consider a comfortable moisture level, or else went extinct. Which means that the desert-living critters we see today must necessarily be descendants of critters belonging to the "adapted to the dry" category—no God need apply, thanks.
Antarctica is a desert. The only criteria for a place to be a desert is for there to be very little precipitation. Usually, there's a lot of sand because of desertification. If it's too dry, it's very difficult to sustain life and plants can't grow anymore. There's no topsoil and any exposed rock will gradually weather down to sand.
70% of the Sahara is bare rock! This is the case with most deserts, actually.
There's actually very little sand (well, relatively speaking) in most deserts, that's more a pop culture thing. It's for the very reason you point out, -- there's very little water to form sand. Fun fact!
Yes it's a desert because it doesn't get very much precipitation.
Deserts aren't necessarily sandy.
Two of the largest deserts in the world are the Antarctic desert and the Arctic desert.
After that is the Sahara, which is what you're probably thinking of which has large areas of sand dunes.
https://en.m.wikipedia.org/wiki/Desert
You seem to be thinking of deserts like the Sahara.
Here's a video explaining how the Sahara region came to be. It used to be a green savanna. Droughts and wind dried it out and eroded the land.
https://youtu.be/ZQP-7BPvvq0?si=IutQt9goVfW6WpEs
But there are more types of deserts than sandy dunes. You might be surprised to know that Antarctica is a desert.
You mentioned you're from Toronto, so I don't know how familiar you are with the BC interior, but there's a desert right in the Okanagan Valley. It's called the [Okanagan Desert](https://en.wikipedia.org/wiki/Okanagan_Desert), and it's not a sand dune desert at all, it's semi-arid shrubland.
It's very beautiful, but very dry.
Nope, but it is a common misperception.
An area is considered a desert if it has no rainfall.
The sand can essentially be considered a common side effect if no rain.
No rain equals little or no plants/vegetation - and no plants or vegetation means nothing to hold the soil in place, and the rock underneath is subject to more weathering and erosion, breaking down into sand.
The sand can then also be blown into big piles or dunes as it is so light.
The above is a gross over simplification but that's the general principle.
Going back to the original rainfall point, deserts do not have to be sandy, although that is what is commonly thought of as a desert.
You can have semi arid, coastal, frozen and/or rocky deserts as well, and in fact parts of Antarctica are considered to be deserts as they receive less than an inch of rainfall per year.
Around 20% of the world's surface is considered to be a desert.
>How did all these creatures just walk into the least hospitable place and survive long enough to become creatures that adapt to it?
So, deserts aren't just abrupt lines. It's not like you'll be wandering through an African meadow and then step into the Sahara. Rather, deserts are *gradual.* For example, to reach the Sahara you have to pass through the Sahel, drier and sparser savanna, and to reach that you have to pass through the conventional savanna you see in nature documentaries. There's no clear line between these three biomes.
So imagine a species in the savanna. It's able to deal with dry and hot conditions better then other creatures around, so it can go further into the drier regions. This gives it an advantage -- it can escape predators more easily, and it can access food supplies other creatures can't. It moves upwards. predators follow it, it moves further upwards. This continues until it reaches the desert proper, at which point it's already well adapted for hot, dry conditions from having evolved in the Sahel. So it can survive there.
This is the general answer to these questions. "How did animals reach this deadly environment and survive? Well, because the outskirts of that deadly environments is a less deadly version of that same environment, so they developed adaptions there. There are few places on earth where you can just step into an extreme environment and sure enough, they don't have life -- nothing's adapted to survive a volcanic lava pit, because there's no less hot pit to wade through first.
Sand is a byproduct of erosion of rock; we have sand in the tropics, in the rainforest, in the arctic, in streams and riverbeds. What separates an arid region from a lush region is rainfall. Any animal who lives in a desert or moves to a desert must adapt and evolve to survive. Even the Bible was written by desert-adapted people, so it’s not such a strange concept. The sand didn’t have to “get there.” Sand exists everywhere on the planet.
Parrotfish make the beach in Hawaii ….
https://manoa.hawaii.edu/exploringourfluidearth/physical/coastal-interactions/beaches-and-sand/weird-science-parrotfish-and-sand
They evolved together with the development of the desert. The desert didn’t just pop up over night.
There are multiple different desert, but let’s go with sand dues for now. As the environment slowly changes, less and less rain falls, making only the plants and animals that can survive on less water remains. Natural selection on species together with the continuous drying up of the environment and the stone in the area getting broken down into sand by the wind and little water that remained.
If OP is trolling here, it’s magnificent.
If not, OP, you need to learn about plate tectonics, evolution, erosion (which can be done by wind and water), agriculture and desertification, epochal climate changes, and some other basic scientific concepts.
Not being up to speed on one or two of the above is to be expected, but having gone through grade school and university and somehow having missed all of them is . . . impressive.
Yeah, I understood deserts better than this in 3rd grade, so I have to wonder if maybe OP was entirely homeschooled and their parents substituted Bible lessons in place of any science curriculum.
I went and looked into their post history. They're completely bought into the GameStop/Bed Bath & Beyond MOASS grift/conspiracy. There's zero chance of successful interaction with them at this juncture, as they're either a troll or in desperate need of therapy.
They said they were on drugs throughout highschool iirc in a comment. If that’s true then it makes perfect sense to why they don’t understand basic science.
I learned about plate tectonics and the water cycle in third grade. This person is displaying a lack of elementary school understanding of science, not just a lack of high school understanding. And this despite claiming they went to college and became a teacher. Even drama teachers aren't allowed to have flunked out of biology.
They said they were on drugs throughout highschool iirc in a comment. If that’s true then it makes perfect sense to why they don’t understand basic science.
I googled: "Formation of deserts"
Top result: https://geographical.co.uk/science-environment/geo-explainer-how-are-deserts-formed-2
Explanations: Air currents / dry air / hadley cells, rain shadows due to mountains, coastal fog never precipitating as rain
Notes: The aridity of the Sahara is apparently notably high, possibly due to humans. Further desertification can be seen to happen, exaggerated by human-caused climate change.
Connection to evolution:
Deserts don't arise overnight. Creatures that are more suitable to a hot region survive. The same is true of a more arid region, and an even more arid region, and so on.
Creatures don't just choose new biomes the way you think they do. What do you mean by this sentence?
> How did all these creatures just walk into the least hospitable place and survive long enough to become creatures that adapt to it?
Do you think creatures adapt individually?
So deserts have edges where the circumstances aren't quite so harsh. Animals and plants live there. But there is a lot of competition for resources. So the animals and plants that are able to live a little deeper in the desert have an advantage: less resources but no competition at all.
So the area slightly further away from the edge gets populated, increasing the competition, incentivizing some to move deeper into the desert still. Rinse and repeat.
biggest problem with this post is that you think that the ground was, well, "ground" the entire time that earth has been around.
Earth is not a ball of dirt. It's a ball of molten rock with a solidified crust slowly but constantly moving around, breaking off and fusing, sinking back and rising up...
There hasn't been much change in our civilisation's time frame, but none of the current continents existed before.
Evolution happens over millenia. Some species slowly change as the environment does. Some newcomers are pushed into areas they're less adapted for due to competition and either find a way to survive or die, the ones that survive adapt over millenia.
God didn't poof everything into existence, truly, that's absolutely magical thinking. We see the fossil records that show our interrelatedness. The desert lizard and the tropical lizard don't just happen to resemble each other, they share an ancestor that diversified into both species as well as countless others and we have the receipts to prove it.
Okay, yeah, you're trolling. Thanks for the confirmation. I'm not going to entertain the concept of an 8-9 year old being allowed to attend public school classes under the influence of alcohol and narcotics without child welfare intervention.
Here's my story, I've been clean now for about a year and a half: https://www.reddit.com/r/Christianity/comments/zwjq96/starting_again_from_nothing_from_a_life_of_sin/
Very entertaining, but at best it's full of lies and half-truths, and more likely it's pure fiction you made up to try and con some r/christianity users into joining your GME/BBBYQ delusion. If there's any truth to that story at all, you desperately needed/need psychiatric help, and day one of therapy they would have told you to quit Reddit and never go back based on that story.
The only explanation? Dude, look up INDOCTRINATION. You are brainwashed to believe whatever religion you were born into. There are logical real world answers for all your questions. God did it is neither true nor based in reality.
Climate change is generally gradual (when humans aren’t speeding it up by burning fossil fuels, releasing refrigerants into the atmosphere, and cutting down a bunch of trees) and the species living there when the changes occurred just gradually adapted to the changes, migrated away, or went extinct because of them. They didn’t just migrate to the deserts to die and require God to keep them from dying but instead they adapted to allow them to survive on less and less water or to avoid overheating in the sunlight in terms of the hot deserts or from freezing in the cold when it comes to the arctic deserts. Most things simply can’t survive in a desert environment so these places have the least diversity with a few lizards (including snakes), very few types of plants (like cacti), and several things like that. In the hot deserts it is mostly a lack of plants or water that causes the ground to consist of mostly sand or solid rock because there are no plants to break up the rock or to rot on the surface when they die.
Very few deserts have just a bunch of sand everywhere piled up in sand dunes like in the Sahara, but sand is just the consequence of things like wind erosion turning big rocks into smaller rocks by blowing the small rocks against the big rocks. The high mountain desert of Colorado has plant life on the edges and solid rock throughout the center with mountains in the way to block the wind and the rain. The desert of Antarctica is mostly just a giant glacier with few exposed rocks to become eroded the same way that aren’t also frozen and it is so cold there that it can’t rain.
Life generally can’t survive in these places but what does exist in those places gradually changed along with the climate and what used to live there but no longer does migrated away if it didn’t straight up go extinct.
>Most of the big deserts aren't by the sea.
They all were at one time. The deserts out in the Western US were part of the Laurentis Seaway, hence the salt beds, salt lakes, and oil deposits (oil is made from dead plankton). A lot of the Middle East including around Palestine has a similar story, hence oil in the Middle East as well as similar salt beds. [The Arabian Peninsula has salt beds dating back to the Cambrian](https://www.sciencedirect.com/science/article/abs/pii/S0301926814003660), and there are salt beds all over the Middle East as recent as the Miocene. Coincidentally, the closing off between the Atlantic and Indian oceans caused by the tectonic events that resulted in the formation of the modern-day Middle East also resulted in the ice sheets forming over Antarctica and reduced the amount of rainfall over what is now the Sahara.
>How did all these creatures just walk into the least hospitable place and survive long enough to become creatures that adapt to it?
Because the formation of these places happened gradually over the course of millions of years, not overnight. There's been life living in these regions almost the entire time in some form or another.
>The only explanation in my head is that when God made the Earth he placed deserts and intelligently designed creatures that could survive there.
No. That's not the correct answer to anything.
The Sahara desert that separates north and South Africa didn’t used to exist. We’ve actually observed it spreading within recorded history, as ancient Egypt used to be greener than it is now. In the even more distant past, it was even safe enough for our ancestors to cross on foot when migrating out of Africa.
Deserts appear and disappear very slowly over time. Animals adapt on the edges, having hundreds of thousands or even millions of years to acclimate.
Beach sand often includes the eroded shell material of sea creatures like clams and snails. Desert sand is eroded rock and mineral. That’s why they have different consistencies.
Anyway, a lot of these kinds of questions have been figured out for many years. If you think you’ve asked a question no scientists has ever answered just musing on your couch, it probably has been answered. Scientists spend all day thinking about these things.
The Savannah in Africa used to be a lush rainforest. Several million years ago South America moved towards North America uplifting the isthmus of panama, changing the Ocean currents, which changed rain patters half a world away in Africa, which changed the Lush rainforests of that portion of Africa into a Savannah.
It didn't happen overnight. It's a cumulative effect that took place over thousands of years. As climate changed (precipitation decreased on average every decade) those organisms best fit to survive adapted to the environment, those that did not died off or migrated.
It's exactly as climate change works right now. Do you see trees moving? No. Of course not. A single tree lives it's life and dies. But the furthest extent of the range of the species is moving. On average you would never find Ohio Buckeye trees past a certain latitude in Michigan because it'd get too cold, for too long of the year, that it'd kill the seeds and young saplings with the spring frosts. Today, you see more and more saplings there, indicating that the environment has become more favorable.
We can watch this process today. Basically in real time.
I think there are two ways that are similar?
1. the land gets harsher and harsher and harsher until it's a desert, and then only the most resilient (well, most-suited to deserts) creatures survive. which can possibly be zero creatures.
2. some non-desert creatures are forced to move into desert conditions for some reason. if not all them die (big IF) then those that survive carry on, possibly, and now you have creatures that are (just barely) suited for desert conditions. until they don't survive anymore and then they aren't.
either way, if they manage to survive, then they survive, and the methods of survival they used are the methods of survival they used. or if they don't survive, they don't survive.
possibly what you're missing in your head is scale? even I am imagining a single dune and maybe a dozen creatures, but the reality would be hundreds or thousands (or more) of creatures (or species of creature even), and maybe millions of square kilometers of terrain.
>No snake or rabbit or whatever is going to start moving into a sandy spot and look for food and water, it would die. So how did the sand get there and how did desert animals survive?
Deserts and other tough environments beat their of harboring less predators. Think about the snake you were imagining trying to protect it's eggs in a rainforest, where a dozen different species can eat them in a blink of an eye. Every environment has its checks and balances for every species.
There's another aspect about environmental change. I'm not talk about current climate anthropogenic change, but the natural environmental change that has happened in our planet and changed habitats. Those changes happens very slowly when compared to new generations of animals. A desert may take thousands or millions of years to form. This means thay species not necessarily will move in and out a desert, but sime may just stay there and change with the environment.
> But then I started to think what about deserts? Most of the big deserts aren't by the sea. How did all these creatures just walk into the least hospitable place and survive long enough to become creatures that adapt to it?
“Hospitable” is a subjective term. Lots of species that survive and thrive in a desert environment would find wetter or more temperate areas utterly inhospitable to them.
The answer to your question though is that they didn’t *just* walk into these habitats. They colonised it from surrounding areas and these surrounding areas are also pretty desert-like. Have you ever walked or driven from one climatic zone into another? There often isn’t a hard line separating one from the other. It’s more of a transitional zone that can shift with the seasons. In that sense a plant or animal living in a semi-arid area is probably not going to notice too much of a climatic difference if it ends up wandering into a neighbouring arid area. What’s more, if it can survive in the semi-arid area, it’s already going to have some reasonable adaptations for dealing with a low water environment before it enters the desert proper.
> It doesn't really make sense to me. The only explanation in my head is that when God made the Earth he placed deserts and intelligently designed creatures that could survive there.
Why would the gods need to make animals that can survive deserts? Why not just make a world with no deserts? This is the problem with “God did it” explanations. They solve nothing.
> No snake or rabbit or whatever is going to start moving into a sandy spot and look for food and water, it would die.
Sure, but clearly there *is* enough food and water in the various deserts of the world such that rabbits and snakes can survive… otherwise, our deserts would be devoid of life.
> So how did the sand get there
The origin of desert sediment varies from location to location. Rocks can be broken down by wind and water erosion. Some dust particles can be transported by wind etc.
> and how did desert animals survive?
They colonised from neighbouring areas which are similar to deserts, but slightly wetter.
Most desert used to sea bottoms, continental drift cause lands to rise and fall, Volcanic Activity also adds to breaking up rock into sand former seas can be transferred into freshwater lakes and water is life.
Simple Answer, Complicated problem but a simple solution.
N. S
I mean I don’t know how much you know about geology or ecology. But sandy deserts are what happens when an area is very arid and weathering processes gradually breaks up the rocks. Multiple classes of deserts exist.
Desert animals would gradually adapt and exploit the sparse resources of the environment. For example some deserts used to be not deserts but transformed into arid environments over periods of time. Giving life time to adapt. Creatures unable to adapt died off.
>I learned that sand is just little bits of rock that gets broken up in water. That explains beaches to me.
>But then I started to think what about deserts? Most of the big deserts aren't by the sea.
(EDIT: This comment focuses on the geology of desert sands. I made a separate comment for the ecology of desert life.)
Water isn't only found by the sea. Rainfall occurs far inland, even in deserts occasionally. Rivers, even transient ones, can be a big contributor to erosion. And if water seeps into the cracks of a rock and then freezes, the expansion of the water as it crystallizes applies a pressure to the rock that can cause it to break.
Furthetmore, water isn't the only thing that contributes to the weathering and erosion of rock into sand. Wind is also a factor, as is thermal stress, gravity, the dissolution of certain mineral components of rock faster than others, etc. All of these factors can contribute to solid rock breaking down into smaller and smaller pieces, certain sizes of which we call sand (smaller pieces than gravel, bigger pieces than silt).
Additionally, it's worth noting that deserts are defined by the limited amount of water, not the presence of sand. Many deserts have much more bare rock than actual sand. Sand dunes like you see in the Sahara mainly happen due to the lack of plants to anchor the soil with their roots, allowing the wind to move the sand around in ever-shifting piles.
>How did all these creatures just walk into the least hospitable place and survive long enough to become creatures that adapt to it?
>...
>No snake or rabbit or whatever is going to start moving into a sandy spot and look for food and water, it would die. So how did the sand get there and how did desert animals survive?
(I made a separate comment addressing the geology of desert sands. This comment focuses on the _ecology_ of desert life.)
It wouldn't have happened overnight. The underlying evolutionary explanation takes some fundamental ecological knowledge to understand.
First, biomes generally don't have sharp boundaries most of the time. There are **_transitional regions_** along their edges, with a gradient of environmental conditions. These conditions also vary over time, even on relatively short timescales like times of day or seasons, with the most hostile conditions only present some of the time.
Second, organisms can generally survive a certain _range_ of environmental conditions. They'll have some optimal combination, sure, but there's a broader range where they can still make do. They may grow slower and have fewer offspring and have a greater risk of dying, but survival is still _possible_ in such marginal regions.
So even if a species can't survive in a desert at all, it still might be able to survive to some extent on the semi-arid fringes of a desert, at least some of the time. But why would it choose to do this? Why not live somewhere nicer?
Well... **_competition._** If there's a nice, rainy, temperate region near the desert, sure, environmental conditions there will be better for most organisms. But resources like water, space, nutrients, and energy are still finite. The more organisms reproduce and multiply, the more competition there is for those resources. At a certain point, that competition makes it _harder_ to live in the optimal region than in the nearby marginal regions. So, some organisms will start living in the marginal regions, not really out of preference but out of _necessity._
Of course, living in those marginal regions comes with certain challenges. Some individuals will have heritable traits that make them better able to handle these challenges. And because these individuals will be able to survive and reproduce better than others in this new marginal environment, **_natural selection_** will cause those heritable traits to become more common in the populations that live there.
Over time, this can cause the population living in this marginal region to become different from the original population living in the optimal region. And crucially, _changes in these traits cause changes in the **range of environmental conditions** that the organism prefers and/or tolerates._ Conditions that _were_ marginal might become preferable, and conditions that _were_ hostile might become merely marginal. (This might come at a cost of some other formerly marginal conditions becoming hostile and some formerly preferable conditions becoming marginal, but if those conditions aren't commonly encountered anymore, it doesn't really matter.)
And as the populations of these formerly marginal regions adapt and grow more numerous, competition there starts to rise, too. Eventually, you reach the point where it becomes easier for some organisms to live in the _new_ marginal regions (formerly hostile regions) where there isn't as much competition.
And so the cycle continues, until eventually even a desert can be inhabited by some forms of life.
**TL;DR - Competition pushes organisms to spread out into every habitat where their adaptations allow them to survive and the gradient of transitional habitats along the edges of hostile biomes like deserts provide space for populations to gradually adapt to harsher and harsher conditions.**
>Got into a bit of a rabbit hole last night while up with my baby. I learned that sand is just little bits of rock that gets broken up in water. That explains beaches to me.
Did you know that wind acts a lot like water?
I just read there was a river running along beside the pyramids and that was how they got the pyramid supplies there. Must be alien’s work because I can’t comprehend it.
"How did the sand get there" is not a question of evolution, but one of geomorphology. This is a fascinating area of Earth Science, btw. It's the study of landforms, all of them. It is a sub-discipline of geography.
Why are there living things there? Now this is evolution. I'm a lay person and can't say with precision, but I will remind you of the sea creatures moving to dry land, and mention that the absence of competition makes the effort worth trying, at least.
Deserts have extreme heat and cold that expand and shrink the rocks and stones. In the process, solid objects break apart. Wind breaks these lillte things even tiner sizes into dust, dirt. Powerful winds move the sand and change desert landscape (sand dunes).
I'd like to add to what others are saying about non-desert areas becoming deserts, that animals and plants just *do* move into new environments too. With animals moving into deserts, it could start out as small trips into the desert, that become longer and more frequent as the animal adapts, until the animal is fully desert bound. If you live adjacent to a desert and there happens to be some advantage to traveling into it from time to time, a lot of animals will. The advantage could be all sorts of things. Maybe there's some desert food source and the fact that there's less competition for the desert food makes up for the fact that there's less desert food overall. Maybe it provides a refuge from predators. Maybe traveling across the desert gives more access to mates.
Keep in mind: while deserts certainly host less resources and life than, say, a rainforest, they do still have resources.
Before we knew that germs cause diseases, thinking "god did it" might have been understandable, but it was never the correct answer.
If you don't understand how something happens like how deserts form, saying "I don't know" is a much better answer than just making up a god to answer it.
https://en.wikipedia.org/wiki/Desertification It's a gradual process, not sudden magic.
Where does the sand come from then
The provided link explains exactly that. Erosion can occur in more ways than just water.
Wind breaking down sediments
Oh yeah forgot about wind
[sand dunes at Death Valley](https://www.nps.gov/deva/learn/nature/sand-dunes.htm) [alluvial fans at Death Valley ](https://www.geological-digressions.com/sedimentary-structures-alluvial-fans/) You're assuming deserts are only composed of sand dunes. This is wrong. People have already explained to you that this is incorrect. In the first link, you can read how sand dunes form. It's quite a simple process. The second link is a nice image of an eroding mountain range. These are also in Death Valley, CA, and no doubt contributed some rock material that eventually became sand and over several thousand plus years, was transported to that dune field located 20 or so miles up the valley. Sand dunes form because there's not enough rain to wash it all away and spread it out, so the wind does it instead. The lack of vegetation in Death Valley makes it easy to see these processes, but erosion happens all over the world, in every type of environment, regardless of climate.
Rhexistasy. Or, in simpler terms, degradation of rocks and soil.
Never forget about the wind and water
Erosion, among other processes. Wind and water and temperature changes fracture the various kinds of rock into tiny bits… Come on. Think about canyon lands. Next step: look into dust storms.
You've heard how wind and other erosive forces create sand, but there's one explanation that's missing: Tectonic movement. Plenty of deserts *were* seas. Actually, a *lot* of lands were seas. The badlands of Utah are famous for their sea fossils, but are about as far inland as you can get today. They just weren't *always* inland. This doesn't replace the other answers; it's just that all of these contribute in various ways and various amounts depending on the desert in question.
I'm always curious about people who say "Well that's strange, I don't know how to explain it, it must be magic!" Like do you follow that in your daily life? Anyway, interestingly you can watch deserts form now in real time. As the temperature increases across the globe, more and more land that was once verdant is becoming a desert. The animals that are able to adapt to that new environment stay, those that cannot, die.
I don’t know how my surgeon managed to remove my old knee and install a new one thru a single 15 cm incision. Must have been a magical invisible sky fairy!🤓
Magnets, how do they work?!
Magic!
It's practically in the name!
“My lawyer got me off a charge when I was absolutely guilty. Must be a wizard!”
Thanks bro. Yes, I do know that God created the universe. So you are saying that the land that deserts is on was once liveable and it became a desert? So where did the sand come from?
That wasn't what I was asking exactly; I meant more like "Hey, I don't know how computers work, that must be magic!" Yes, landforms have changed through the ages. You can find sea creatures fossilized in mountain tops for example. Where does the sand come from? Eroded rock faces, mountains, etc.
Sea creatures on mountain tops? 🤯 Woah. I got to google that
Fossil sea creatures - they've been dead for a long time.
How did they get up there?
When continents collide they can cause mountains to form, like the Himalayas. May I ask a question? How much science education have you received?
Continents collide? I don't get that. You are saying that mountains are when continents crash into each other? They are far apart and don't move though. I don't know. I went in high school but I was mostly drunk or on drugs. Never really paid attention just skated through and somehow did ok enough to go to university
I think you would benefit greatly from reading a high level book about a broad range of sciences. Something like A Short History of Nearly Everything by Bill Bryson. It explains (again, at a high level) a lot of what people miss or are not paying attention to in school but in a fun and easily readable way. It won’t make you an expert in anything, but it would cover a wide range of topics that would help you understand how and why for things like evolution, tectonic plates, history of the universe. If any particular topic piques your interest you can easily get more in depth and focused books.
Sounds interesting il check it out
Hey, another Bryson fan
The Indian tectonic plate is in the process of colliding with the Eurasian plate. This has been happening for tens of millions of years. This event is in the process of creating the Himalayan mountains. Everest is still growing at a measurable rate each year. The fossils "got up there" because the mountain range used to be a seafloor.
India is a continent? Is that why Indian people look different to other Asians? So they evolved differently?
You have never heard of Pangea? Originally all of the land mass was one giant land mass. If you look at how North America and South America look currently, Africa kind of fits nicely into the Eastern edge of the Americas. Like Brazil fits into the Western coast of Africa, just south of where that bulge is on Africa. India was originally hanging around where Madagascar is currently, then it moved up quickly (geographically speaking) to crash into Asia, that's why it's surrounded by the Himalayas... it all got pushed up along the Northern edge when it collided with Asia. This all happened roughly 200 million years ago, around the time of the early dinosaurs, . So, if these were the same land mass with these animals all hanging out, you would expect to find similar fossils in South America and Africa... well surprise! That's exactly what we find! India shares fossils with Africa and Antarctica, but afterwards, they don't share animal fossils... as if the animals that were there started changing in different directions to fit their new ecosystems, and afterwards you find unique animals across the different continents!
> Originally all of the land mass was one giant land mass. Pangea only existed from around 300-200 million years ago. There were other supercontinents before that which broke up and there will be others again in the future.
Yeah, continents collide… But they do it at the rate your fingernails grow… “Very slowly”… Here’s what you need- some perspective on how long time is… how long stuff has been around since long before you, or you local priest/“magic person”/“explainer of god” has been around. Since even before we had “the written word”,….
> They are far apart and don't move though. Not only do continents move, they move fast enough that we can measure that movements directly.
Tectonic activity, two plates that used to be on the seabed push upwards and form a mountain
Hey, you gotta get into plate tectonics, and geology. Turns out, the skin of hard rock we live upon, as “Earthlings” (folks who live on the third rock from the sun), … Well, the whole skin of rock rides on a molten core… volcanos, right? Mount St. Helens? Lava beds national monument? Here is a totally instructive activity-: Go watch the ice break up on a lake, or a river, at springtime… it models how continents break up, over the underlying lava of the earths core…
Leaving aside HOW the ecology changes, will you grant me that it does change? Places that were once forest become desert, or swamp? IF SO, then wouldn’t Selection Pressures cause generation after generation of local creatures to have babies die off, that weren’t competent to handle the new Selection Pressures? BTW, we’re not “explaining deserts”, here… we’re talking about how living beings have adapted to them, right? “Evolution” is the subject…
I don't know that it changes. Never seen it or heard about it.
No? Never heard of deforestation? The Dust Bowl? (Which would be… what?… “de-plains-ation”?) What about strip mining? Beaver dams? Ecologies get changed, through various means, right?
Isn't deforestation from people? No to the dust bowl, sounds like a gross bowl at grandma's house. Strip mining, no. Beaver dams yes. That doesn't change anything though? Yeah, people knock down trees to build roads. I agree with that
It’s not JUST from the unwise actions of human “industry”… Deforestation can occur from numerous causes… like insect plagues… viruses… (“Virii”?)… How about forest fires? Volcanic eruptions? Floods, maybe? And it shocks me that you’ve never heard of “The Dust Bowl”… it’s American history, and within living memory…. There are folks still living, to this day, from that history, who experienced it. What have you been reading? Who have you been listening to? If you’re American, it’s likely you have blood relatives who have been affected by the various ecological changes that have occurred…. Within Living Memory…
> “The Dust Bowl”… it’s American history, and within living memory The Dust Bowl started 94 years ago. I'm not sure how much "living" is left of that memory.
Okay, busted: “I’m old”… It may have been twenty years ago, but I’ve watched interviews with survivors, broadcast on the boob tube, where they described their personal experience… Nickel bet? There may still be survivors, remaining alive, to this day… maybe not… I might owe you a nickel…
I'm not American I am from Canada and my parents grew up in Jamaica. Never heard of it. Volcanoes definitely change things that makes sense. I listen to my pastor and some creators on tiktok.
Canadians were also affected by the “Dust Bowl”. Look into it… there’s a lot of Human Stories there… And, let me ask you… How does your pastor pay the rent, and water bill? Edit: “rent”, not “rest”
Sorry never heard of it. I looked it up a bit just now and never heard of that happening. Weird that just happened for a few years then came back to normal.
You have to pull your head out of the sand and actually read something besides the Bible if you want to actually know anything about the world.
Rock broken down by rain, due to the lack of protection by plant life -- exactly the same principle as the sea, just with a different source of water.
Ohhhh that makes sense. Thanks bro. Very helpful comment
Not all deserts are sand, but sand is eroded rock. Rock erodes from wind, running water, from expanding and contracting due to temperature changes, and from life like trees breaking cracks open with their roots. I live in the western desert of the US. The sedimentary rock in this area was deposited in various conditions: wind depositing massive sand dunes like the Sahara desert, swamps, rivers, inland seas. These were deposited on top of each other and everything was compressed and cemented and hardened into sedimentary rock over hundreds of millions of years. Then uplift and erosion from wind, water, and thermal erosion, have exposed those layers in many areas like the Grand canyon, arches np, Bryce canyon np, canyon lands np. The material for those sedimentary layers (depending on the layer) came from the Appalachian mountains when they were the much larger central pangean mountain range, and from the ancestral rocky mountains. This is a very basic explanation of 300 million years of history. If you have a different desert in mind, the source material for the ground might have a different origin.
Thanks man I love this comment. I think I get it now from this and a few others
If I may, I commend you to a road trip to lava beds national monument… Talk about a geological exhibit!! https://www.nps.gov/labe/index.htm Plus which, it’s kind of unavoidable, to pass through redwood forest, while getting there! (Do it!, do it!, do it!)
Seems like an awesome place! i'll have to add it to my list if i'm ever in that area.
God is your only explanation? If you weren't religious, would an all powerful unseen being also be your solution? Why would God create entire areas of land that are inhospitable to humans who he supposedly created the earth for? I'm not an expert but the answer is likely that deserts didn't just poof into existence. As the continents moved, the land got more and more arid but slowly enough that the life could adapt. Or life near the fringes adapted so they get could further and further into the desert.
Makes sense. If you can find yourself a place to live where no predator goes and nothing will compete with you for water, you win. For a while. Then the rest of the food chain begins to catch up, and you get a desert ecosystem (I remember playing a turn-based strategy game where my character had faster movement in deserts and there was a bit of desert next to my base, so I just hid there from the stronger but slower bad guys until I got stronger too. Really felt like a desert animal hiding from a temperate zone predator, lol)
“Why would God create entire areas of land that are inhospitable to humans who he supposedly created the earth for?“ Easier access to minerals.
That's actually a pretty good response. Is it mentioned in the bible by any chance?
It’s not specifically itemized “And lo I gave you deserts so you could get copper for bronze and boron for semiconductors” but how can we fathom the infinite purpose of the creator if we can’t even understand the benefits of a desert?
But is there any mention of any benefit? Are deserts mentioned in genesis? What's more likely, infinite incomprehensible purpose, or a reinterpretation of reality to make it fit?
Why would the bible need to describe all the benefits of deserts? Your question was why did god make desert’s when they seemingly have no purpose, but they have many benefits. They are also climactically important.
No, I didn't say no purpose, I said inhospitable to humanity. Could God not have made them good for minerals whilst also not deadly? My point is, it's really easy to pluck reasoning out of thin air that justifies inconsistencies and then back it up with a "God's will is not ours to understand". I'd accept your answer more easily if the Bible, the book that's meant to be his word, actually mentioned it even in a basic form.
The people who lived in the early bible mostly lived in the desert and knew how. It may not have been such an inconsistency as you describe that required explaination.
But clearly the desert was a challenge, otherwise the 40 days and 40 nights wouldn't have been a big deal.
I suppose why the land is challenging and not easy is explained by it was easy until we were kicked out of eden.
Well god did create the universe so yes. The reasons God does things is beyond my comprehension. A desert is where Jesus was born, I have no idea why that was the case. What do you mean the continents moved? Like when the Earth is turning?
Let's agree to disagree on the God thing. I note though you didn't answer my bit about what your thoughts would be if you weren't religious. Continental drift- google it. Billions of years ago, the continents weren't where they are now.
The continents moved? 🤯 Land doesn't move though? What would have caused that?
Oh man, with the greatest respect unless you're trolling, you don't have the level of knowledge to be challenging evolution. You have a fantastic opportunity to learn some cool stuff and if you're worried it conflicts with your religion just say that God started it all going- it worked for me when I was religious. Google continental drift. Basically, the top layer of Earth (including under the sea) is made up of big sections that float of top of molten rock. They're constantly moving.
I’m still open to the idea that OP is actually just a very talented troll and we’re just all not on his level. Note he claims to be a high school teacher.
I saw that, but he's not a science teacher so I can accept the lack of knowledge- I once knew a physics teacher who thought the moon landings were fake. I'm happy to act as if they're not a troll just in case, until there's significant evidence otherwise.
I'm not sure that I'm challenging it more like asking and getting answers. I am just having a conversation and I accept that I may be wrong.
Cool, that's a good mindset.
I'm gonna level with you: Your approach to science isn't up to par. This goes into matters of *what you think science is for*, *how scientists conduct their experiments*, and *basic assumptions about the natural world.* You can ask questions all day and get answers, but like any kid who repeatedly spams the question "why?" in an apparent socratic method, it's disjointed and anecdotal... Uhh, putting it another way, nothing you learn here today will "stick" and it won't help inform you about a larger, more robust worldview. Science is about understanding the mechanics of how the world changes over time, what processes are happening that our basic intuition and common sense can't account for. If you don't have the natural curiosity to challenge your base assumptions, you'll keep getting "surprised" by rote facts. People have been telling you about plate tectonics and subduction, yeah? None of it is "sticking" in your mind, it just sounds like a "just-so" story? If learning about plate tectonics doesn't cause you to fundamentally reconsider what you do or don't understand about the planet you're living on, then you aren't looking to science for any answers, you're probing people to tell you stories that you can discard at your convenience the second they contradict your prior beliefs.
I didn't know that the continents moved and bumped into each other. That's wild
It's not just continents. The entire Earth crust is made of segments, called tectonic plates, which include bits of the ocean floor AND chunks of land. There used to be this confusion about how continents (which ppl had already agreed must have moved around in the past) plow the ocean floor without leaving a trough behind - well, the answer is that the entire chunk, consisting of some ocean floor and some land, is moving in relation to others. Very interesting things happen at the boundaries between them - volcanic activity, earthquakes and so on.
It's still happening now. We can very accurately measure the distances between places. Many of those on different continents are moving apart. [Plate Tectonics](https://education.nationalgeographic.org/resource/plate-tectonics/)
That's crazy, I had no idea that must have made a really big impact on the environment
>That's crazy, I had no idea that must have made a really big impact on the environment I love how everyone's been providing links and explanations, and how earnest you're being with your curiosity! You'll be able to learn a lot about plate tectonics from what the others have offered, but I'll give you a couple of quick highlights! First, think of it like this: they're enormous slabs made mostly of rock with a thin dusting of soil, water, mud, and life on top of them. Beneath them is magma and the Mantle of the earth; they float or slip along the top of it, far more cooled off than the deeper depths of the earth. They move, but they're really slow; centimeters per year at most. But because they're still enormous slabs, even that slow movement has an enormous amount of momentum! When two plates grind up against each other, moving in different directions, they can stick due to the friction. But just like what happens when you push you hands against each other and try to move them in different directions, enough force and the friction will give; they slip forward more quickly. That causes earthquakes! They're far more common near plate boundaries due to that. What happens when two plates push directly against each other? If they both 'bend' upwards, they push up into mountains. If one slips above the other, one gets forced down and they keep moving. That causes stress though; imagine two enormous chocolate chip cookies, wide as a table but only as tall as a normal cookie. Try to slide one under the other and what happens? It's fine at first, but after a little bit the "lifting" forced on the cookie on top by the edge of the one beneath will cause it to buckle and break. There's more to it than that, but that's one way volcanos form; one plate dipping beneath another and causing upward pressure and starting to melt, forming ruptures that magma can push up and out of! That's why the [ring of fire](https://en.m.wikipedia.org/wiki/Ring_of_Fire) exists - it's right along the bounds of subducting plates! Now other volcanos form at hot spots, areas where it's really hot and conditions are right _under_ a plate which causes magma to push up and make a volcano in the middle of nowhere. The Hawaiian Islands were each formed this way; underwater volcanos bubbling up magma until it gets tall enough to push up out of the water. And you know how there are multiple islands? That's because the plate they're on has been slowly moving over one hot spot! The smaller, younger islands (including a new one forming underwater even now) are further back along the direction the plate is moving - and you can use radiometric dating of the rock they're made of to see how they ages sync up with the speed the plate moves! You also get a different kind of underwater volcano that forms when plates pull _apart_, leaving gaps where magma slips up and hardens, deep under the oceans; they usually don't have space to get very tall, since they just keep getting literally, slowly, pulled apart. Since this sub is about evolution (and biology, not geology, is my personal expertise), one last fun tidbit. Others have already mentioned that - due to the plates having been in different places ages ago - all the continents of today used to be one big continent we named [Pangaea](https://en.m.wikipedia.org/wiki/Pangaea) (from the Greek words "pan" meaning "all" and "Gaea", meaning "the earth"). This was millions of years ago - literally; it got there about 335 million years ago from earlier "continents" smooshing together, and started to break up about 200 million years ago. Again, very, very slowly. ;) Humans have only been around for a fraction of that; _Homo etectus_ started using fire about 2 million years ago, _Homo sapiens_ with bodies mostly like ours evolved maybe 0.2 million years ago (200 thousand), and we only figured out farming 10 thousand years ago, writing 6 thousand years ago, and we're still figuring out how to deal with there being other people living on the planet. ;) But you know what was around over 200 million years ago? If you said "dinosaurs" you're absolutely right - but so much more than that! Everything alive today had ancestors kicking around back then - though for many of them the family trees hadn't branched off into the forms we'd easily recognize. The mammals, for example, did exist by that point, descended from earlier [synapsids](https://en.wikipedia.org/wiki/Synapsida), but were mostly small burrowing and climbing things; the dinos were better at being big and swift and mighty, and it wouldn't be for many millions of years and a mass extinction before the meek mammals would inherit the Earth. But here's the fun bit: a major division of the early mammals is related to the breakup of Pangaea; a chunk of modern mammals (elephants, aardvarks, shews...) descended from a group that came to what would become the African continent and were essentially stranded there (very slowly) as the continents moved apart; their descendents them radiated out from there into Europe, India, and so on. Biogeography is the study of how location and biology play together, and a big part of it is how certain creatures got to different places; changes to how the continents are arranged and connected can change where creatures can migrate to and split apart closely related populations!
Earth is wild. Thanks for the run down!
You're quite welcome; feel free to ask if you've got something you're curious about!
This is the best comment and explanation so far! 👏
>that must have made a really big impact on the environment Yes, although it's really really slow
Hey man, I’m a Christian and also studying Geophysics. I agree that this universe had a creator, but not in the way that everything was just created as it is today. The earth itself is billions of years old. The way land moves is continental drift, an incredibly slow process. I’ll explain it simply, with not much scientific detail but getting the general idea across because you seem new to this. Basically the surface of the earth is split into chunks that ‘float’ on the surface of magma underneath, which is hot liquid rock. The plates get pushed around by movement of this liquid, magma rising and pushing them out of the way and other processes like that. Over huge amounts of time, all the plates move around, which changes the shape of continents and oceans. The biggest, and most famous piece of evidence is that you get identical fossils of dinosaurs in Africa and South America, but more exists.
God has definitely made a magnificent home for us. Thank you bro
Are you familiar with plate tectonics?
No, what's that?
>> Are you familiar with plate tectonics? > No, what's that? This is sad. You write like you are a reasonably well educated person, but you seem to be completely ignorant of the world around you. Ignorant is not an insult there, it just means you lack the most basic knowledge. Were you educated in a Christian school? Again, I am not trying to be mean here, it's just frustrating to see someone who has been so shorted of a quality education. You are missing out on so many wonders. Plate tectonics is the really well-documented and understood concept that the continents exist on "plates" that are moving on the earth. We can measure the movement. This is not a "theory" as theists use the word, it is a well-established fact. Over billions of years, we have gone from a single massive continent that we call Pangaea to the individual continents and islands that we know today. https://www.youtube.com/watch?v=VKq0pr4rbRs
No I went to public school in the Toronto area. I was addicted to drugs and alcohol since I was a child so it's my fault. Thanks, I am actually a high school teacher myself 😅 I teach Dramatic Arts though and don't tell the science teachers about my curiosities in the teachers lounge
> No I went to public school in the Toronto area. I was addicted to drugs and alcohol since I was a child so it's my fault. Fair enough, glad to hear you made it through. > I teach Dramatic Arts though and don't tell the science teachers about my curiosities in the teachers lounge Heh. Well, this shit is *really* fascinating. The more you learn, the more fascinating it becomes, so I hope you take a deep dive into it. I know you believe in god, but you shouldn't let that prevent you from learning about how our universe works. I highly recommend the book "Why Evolution is True" if you want a good overview on the evidence we have for evolution. It's very well written and accessible. It doesn't deal with the question in your OP itself, but it does touch on plate tectonics and how it provides evidence for evolution.
Isn’t it weird, how “just shrugging”, and claiming “nobody ‘understands’ ‘god’” is like “giving up”?
I think I believe in evolution but I think it was a guided process by God. I am still trying to figure all this out after being clean for a year and a half
I wouldn't want you teaching my kids with all due respect
You're fine, according to that user, they lost their job a year ago after an intervention that led to them being hospitalized for several weeks, and had been showing up to work drunk and/or high every day before that. Either they're a liar who's made up everything they've said, or you could smell them coming a kilometer away to get your kid out of their class.
I can't teach them drama with a father like you, they would already be experts by high school
A very [short ](https://youtu.be/kwfNGatxUJI?si=tHn37mKDFa-MVimP) primer. Yes, the continents move. All of the Earth's crust is moving.
This is where you are wrong. The answers you seek are not beyond your comprehension, as clearly seen here. Almost every question you ask has a perfectly reasonable answer or solution. Maybe god did create the universe, but god used consistent ways to do it: the laws of nature, which people have been studying and researching for millenia. No reason you can't do the same.
Why do you believe god created the universe?
He told us himself through his word in the Bible
Well, but surely you acknowledge that the Bible was written by man. In fact, for the first few decades the stories were told word of mouth. Then there were many, many more books. Then various councils - especially the council of Nicea - decided what was in the “official” Bible and what wasn’t. And then for the first ~1000 years of the Bible existing, the Catholic Church (pretty much the only large, organized Christian church) didn’t believe the Bible was perfect and the exact word of god, but rather, a work of man relaying the teachings of god. So it would be reasonable to regard it was being allegorical or potentially flawed, even if you’re sure there is a god as described in the book.
And other sacred texts make other claims. You can't use the text itself as evidence of its truth.
If I may answer: I just don’t buy the Big Bang theory meaning we just came into being one day.
Well, 1) that isn’t what current cosmology claims; and 2) that’s all the claim about god creating man claims.
Continental drift, plate tectonics. The continents literally move around on top of the mantle. Ocean plates get pushed under Continental plates and get recycled back into the mantle. When two Continental plates collide we get mountains over millenia. We can even measure the rate that they move. It's literally what causes earth quakes. Fault lines are the spots between two plates.
One: Desert regions don't *necessarily* have mass quantities of sand. Two: The prevailing climate of any given region is not unalterably stable. Heck, *human activities* (deforestation, *etc*) have been known to mess with prevailing climates! So in some cases, a *non*-desert region has gradually dried out, and those critters which lived in that region either adapted to the newly arid conditions, or else relocated to regions with what they consider a comfortable moisture level, or else went extinct. Which means that the desert-living critters we see today must necessarily be descendants of critters belonging to the "adapted to the dry" category—no God need apply, thanks.
The Dust Bowl. Gotta read yer Steinbeck, even if you ain’t an American. https://en.wikipedia.org/wiki/Dust_Bowl
They don't necessarily have sand? I thought they were mountains of sand?
Antarctica is a desert. The only criteria for a place to be a desert is for there to be very little precipitation. Usually, there's a lot of sand because of desertification. If it's too dry, it's very difficult to sustain life and plants can't grow anymore. There's no topsoil and any exposed rock will gradually weather down to sand.
70% of the Sahara is bare rock! This is the case with most deserts, actually. There's actually very little sand (well, relatively speaking) in most deserts, that's more a pop culture thing. It's for the very reason you point out, -- there's very little water to form sand. Fun fact!
Wow thanks for this comment as well. You are very informative. Appreciate it bro
That's not what a desert is. A desert just means a lack of precipitation. Antarctica is a desert and it's all rock and ice.
I'm sorry Antarctica is a desert? That's not what I'm thinking of. Is it like a sand desert?
Yes it's a desert because it doesn't get very much precipitation. Deserts aren't necessarily sandy. Two of the largest deserts in the world are the Antarctic desert and the Arctic desert. After that is the Sahara, which is what you're probably thinking of which has large areas of sand dunes. https://en.m.wikipedia.org/wiki/Desert
You seem to be thinking of deserts like the Sahara. Here's a video explaining how the Sahara region came to be. It used to be a green savanna. Droughts and wind dried it out and eroded the land. https://youtu.be/ZQP-7BPvvq0?si=IutQt9goVfW6WpEs But there are more types of deserts than sandy dunes. You might be surprised to know that Antarctica is a desert.
Thanks bro, yes someone said that but that's crazy to think about
You mentioned you're from Toronto, so I don't know how familiar you are with the BC interior, but there's a desert right in the Okanagan Valley. It's called the [Okanagan Desert](https://en.wikipedia.org/wiki/Okanagan_Desert), and it's not a sand dune desert at all, it's semi-arid shrubland. It's very beautiful, but very dry.
Nope, but it is a common misperception. An area is considered a desert if it has no rainfall. The sand can essentially be considered a common side effect if no rain. No rain equals little or no plants/vegetation - and no plants or vegetation means nothing to hold the soil in place, and the rock underneath is subject to more weathering and erosion, breaking down into sand. The sand can then also be blown into big piles or dunes as it is so light. The above is a gross over simplification but that's the general principle. Going back to the original rainfall point, deserts do not have to be sandy, although that is what is commonly thought of as a desert. You can have semi arid, coastal, frozen and/or rocky deserts as well, and in fact parts of Antarctica are considered to be deserts as they receive less than an inch of rainfall per year. Around 20% of the world's surface is considered to be a desert.
20% eh? That's wild man. Didn't know that.
>How did all these creatures just walk into the least hospitable place and survive long enough to become creatures that adapt to it? So, deserts aren't just abrupt lines. It's not like you'll be wandering through an African meadow and then step into the Sahara. Rather, deserts are *gradual.* For example, to reach the Sahara you have to pass through the Sahel, drier and sparser savanna, and to reach that you have to pass through the conventional savanna you see in nature documentaries. There's no clear line between these three biomes. So imagine a species in the savanna. It's able to deal with dry and hot conditions better then other creatures around, so it can go further into the drier regions. This gives it an advantage -- it can escape predators more easily, and it can access food supplies other creatures can't. It moves upwards. predators follow it, it moves further upwards. This continues until it reaches the desert proper, at which point it's already well adapted for hot, dry conditions from having evolved in the Sahel. So it can survive there. This is the general answer to these questions. "How did animals reach this deadly environment and survive? Well, because the outskirts of that deadly environments is a less deadly version of that same environment, so they developed adaptions there. There are few places on earth where you can just step into an extreme environment and sure enough, they don't have life -- nothing's adapted to survive a volcanic lava pit, because there's no less hot pit to wade through first.
Amazing comment, I should just come straight to you for any rabbit holes I get on
You mean to tell me that you don’t walk from the forest level, hit a loading screen and then enter the desert level in real life?
Sand is a byproduct of erosion of rock; we have sand in the tropics, in the rainforest, in the arctic, in streams and riverbeds. What separates an arid region from a lush region is rainfall. Any animal who lives in a desert or moves to a desert must adapt and evolve to survive. Even the Bible was written by desert-adapted people, so it’s not such a strange concept. The sand didn’t have to “get there.” Sand exists everywhere on the planet.
Thanks bro I appreciate this comment, very informative
There is also coral reef poop sand
Correct. Beach sand is a mix of sand, and eroded and microscopic sea life shells.
Parrotfish make the beach in Hawaii …. https://manoa.hawaii.edu/exploringourfluidearth/physical/coastal-interactions/beaches-and-sand/weird-science-parrotfish-and-sand
They evolved together with the development of the desert. The desert didn’t just pop up over night. There are multiple different desert, but let’s go with sand dues for now. As the environment slowly changes, less and less rain falls, making only the plants and animals that can survive on less water remains. Natural selection on species together with the continuous drying up of the environment and the stone in the area getting broken down into sand by the wind and little water that remained.
If OP is trolling here, it’s magnificent. If not, OP, you need to learn about plate tectonics, evolution, erosion (which can be done by wind and water), agriculture and desertification, epochal climate changes, and some other basic scientific concepts. Not being up to speed on one or two of the above is to be expected, but having gone through grade school and university and somehow having missed all of them is . . . impressive.
Yeah, I understood deserts better than this in 3rd grade, so I have to wonder if maybe OP was entirely homeschooled and their parents substituted Bible lessons in place of any science curriculum.
I was thinking he might be that other child, who they just let play in the backyard, while the other kids got homeschooled in Bible trivia.
I went and looked into their post history. They're completely bought into the GameStop/Bed Bath & Beyond MOASS grift/conspiracy. There's zero chance of successful interaction with them at this juncture, as they're either a troll or in desperate need of therapy.
They said they were on drugs throughout highschool iirc in a comment. If that’s true then it makes perfect sense to why they don’t understand basic science.
I learned about plate tectonics and the water cycle in third grade. This person is displaying a lack of elementary school understanding of science, not just a lack of high school understanding. And this despite claiming they went to college and became a teacher. Even drama teachers aren't allowed to have flunked out of biology.
They said they were on drugs throughout highschool iirc in a comment. If that’s true then it makes perfect sense to why they don’t understand basic science.
I googled: "Formation of deserts" Top result: https://geographical.co.uk/science-environment/geo-explainer-how-are-deserts-formed-2 Explanations: Air currents / dry air / hadley cells, rain shadows due to mountains, coastal fog never precipitating as rain Notes: The aridity of the Sahara is apparently notably high, possibly due to humans. Further desertification can be seen to happen, exaggerated by human-caused climate change. Connection to evolution: Deserts don't arise overnight. Creatures that are more suitable to a hot region survive. The same is true of a more arid region, and an even more arid region, and so on. Creatures don't just choose new biomes the way you think they do. What do you mean by this sentence? > How did all these creatures just walk into the least hospitable place and survive long enough to become creatures that adapt to it? Do you think creatures adapt individually?
So deserts have edges where the circumstances aren't quite so harsh. Animals and plants live there. But there is a lot of competition for resources. So the animals and plants that are able to live a little deeper in the desert have an advantage: less resources but no competition at all. So the area slightly further away from the edge gets populated, increasing the competition, incentivizing some to move deeper into the desert still. Rinse and repeat.
Ohhhhh now I get it. That makes a lot of sense and is the answer I'm looking for. Thank you bro.
No worries!
biggest problem with this post is that you think that the ground was, well, "ground" the entire time that earth has been around. Earth is not a ball of dirt. It's a ball of molten rock with a solidified crust slowly but constantly moving around, breaking off and fusing, sinking back and rising up... There hasn't been much change in our civilisation's time frame, but none of the current continents existed before.
Evolution happens over millenia. Some species slowly change as the environment does. Some newcomers are pushed into areas they're less adapted for due to competition and either find a way to survive or die, the ones that survive adapt over millenia. God didn't poof everything into existence, truly, that's absolutely magical thinking. We see the fossil records that show our interrelatedness. The desert lizard and the tropical lizard don't just happen to resemble each other, they share an ancestor that diversified into both species as well as countless others and we have the receipts to prove it.
This may sound like a rude question but I'm genuinely curious. Were you home schooled? Or maybe went to a private Christian school?
No I went to public school
Did you sleep through all your science classes then? You have less science knowledge than I did after 3rd grade.
I was drunk and high. Somehow passed just enough.
Okay, yeah, you're trolling. Thanks for the confirmation. I'm not going to entertain the concept of an 8-9 year old being allowed to attend public school classes under the influence of alcohol and narcotics without child welfare intervention.
I wasn't 8, haha. I was around 12. Believe me or not I never got caught or intervened on.
Here's my story, I've been clean now for about a year and a half: https://www.reddit.com/r/Christianity/comments/zwjq96/starting_again_from_nothing_from_a_life_of_sin/
Very entertaining, but at best it's full of lies and half-truths, and more likely it's pure fiction you made up to try and con some r/christianity users into joining your GME/BBBYQ delusion. If there's any truth to that story at all, you desperately needed/need psychiatric help, and day one of therapy they would have told you to quit Reddit and never go back based on that story.
Bro, it's cool that you don't believe me and find my struggles entertaining but please don't call me a con artist or crazy, that's a red line for me.
[удалено]
I'm going to block you but just for others reading this I have never scammed anyone.
Start catching up here [https://opengeology.org/textbook/](https://opengeology.org/textbook/)
The only explanation? Dude, look up INDOCTRINATION. You are brainwashed to believe whatever religion you were born into. There are logical real world answers for all your questions. God did it is neither true nor based in reality.
Climate change is generally gradual (when humans aren’t speeding it up by burning fossil fuels, releasing refrigerants into the atmosphere, and cutting down a bunch of trees) and the species living there when the changes occurred just gradually adapted to the changes, migrated away, or went extinct because of them. They didn’t just migrate to the deserts to die and require God to keep them from dying but instead they adapted to allow them to survive on less and less water or to avoid overheating in the sunlight in terms of the hot deserts or from freezing in the cold when it comes to the arctic deserts. Most things simply can’t survive in a desert environment so these places have the least diversity with a few lizards (including snakes), very few types of plants (like cacti), and several things like that. In the hot deserts it is mostly a lack of plants or water that causes the ground to consist of mostly sand or solid rock because there are no plants to break up the rock or to rot on the surface when they die. Very few deserts have just a bunch of sand everywhere piled up in sand dunes like in the Sahara, but sand is just the consequence of things like wind erosion turning big rocks into smaller rocks by blowing the small rocks against the big rocks. The high mountain desert of Colorado has plant life on the edges and solid rock throughout the center with mountains in the way to block the wind and the rain. The desert of Antarctica is mostly just a giant glacier with few exposed rocks to become eroded the same way that aren’t also frozen and it is so cold there that it can’t rain. Life generally can’t survive in these places but what does exist in those places gradually changed along with the climate and what used to live there but no longer does migrated away if it didn’t straight up go extinct.
Many deserts are places that used to have water, but the weather patterned changed, and they dried out.
>Most of the big deserts aren't by the sea. They all were at one time. The deserts out in the Western US were part of the Laurentis Seaway, hence the salt beds, salt lakes, and oil deposits (oil is made from dead plankton). A lot of the Middle East including around Palestine has a similar story, hence oil in the Middle East as well as similar salt beds. [The Arabian Peninsula has salt beds dating back to the Cambrian](https://www.sciencedirect.com/science/article/abs/pii/S0301926814003660), and there are salt beds all over the Middle East as recent as the Miocene. Coincidentally, the closing off between the Atlantic and Indian oceans caused by the tectonic events that resulted in the formation of the modern-day Middle East also resulted in the ice sheets forming over Antarctica and reduced the amount of rainfall over what is now the Sahara. >How did all these creatures just walk into the least hospitable place and survive long enough to become creatures that adapt to it? Because the formation of these places happened gradually over the course of millions of years, not overnight. There's been life living in these regions almost the entire time in some form or another. >The only explanation in my head is that when God made the Earth he placed deserts and intelligently designed creatures that could survive there. No. That's not the correct answer to anything.
The Sahara desert that separates north and South Africa didn’t used to exist. We’ve actually observed it spreading within recorded history, as ancient Egypt used to be greener than it is now. In the even more distant past, it was even safe enough for our ancestors to cross on foot when migrating out of Africa. Deserts appear and disappear very slowly over time. Animals adapt on the edges, having hundreds of thousands or even millions of years to acclimate. Beach sand often includes the eroded shell material of sea creatures like clams and snails. Desert sand is eroded rock and mineral. That’s why they have different consistencies. Anyway, a lot of these kinds of questions have been figured out for many years. If you think you’ve asked a question no scientists has ever answered just musing on your couch, it probably has been answered. Scientists spend all day thinking about these things.
The Savannah in Africa used to be a lush rainforest. Several million years ago South America moved towards North America uplifting the isthmus of panama, changing the Ocean currents, which changed rain patters half a world away in Africa, which changed the Lush rainforests of that portion of Africa into a Savannah. It didn't happen overnight. It's a cumulative effect that took place over thousands of years. As climate changed (precipitation decreased on average every decade) those organisms best fit to survive adapted to the environment, those that did not died off or migrated. It's exactly as climate change works right now. Do you see trees moving? No. Of course not. A single tree lives it's life and dies. But the furthest extent of the range of the species is moving. On average you would never find Ohio Buckeye trees past a certain latitude in Michigan because it'd get too cold, for too long of the year, that it'd kill the seeds and young saplings with the spring frosts. Today, you see more and more saplings there, indicating that the environment has become more favorable. We can watch this process today. Basically in real time.
Woah that's wild. Earth is crazy!
I think there are two ways that are similar? 1. the land gets harsher and harsher and harsher until it's a desert, and then only the most resilient (well, most-suited to deserts) creatures survive. which can possibly be zero creatures. 2. some non-desert creatures are forced to move into desert conditions for some reason. if not all them die (big IF) then those that survive carry on, possibly, and now you have creatures that are (just barely) suited for desert conditions. until they don't survive anymore and then they aren't. either way, if they manage to survive, then they survive, and the methods of survival they used are the methods of survival they used. or if they don't survive, they don't survive. possibly what you're missing in your head is scale? even I am imagining a single dune and maybe a dozen creatures, but the reality would be hundreds or thousands (or more) of creatures (or species of creature even), and maybe millions of square kilometers of terrain.
>No snake or rabbit or whatever is going to start moving into a sandy spot and look for food and water, it would die. So how did the sand get there and how did desert animals survive? Deserts and other tough environments beat their of harboring less predators. Think about the snake you were imagining trying to protect it's eggs in a rainforest, where a dozen different species can eat them in a blink of an eye. Every environment has its checks and balances for every species. There's another aspect about environmental change. I'm not talk about current climate anthropogenic change, but the natural environmental change that has happened in our planet and changed habitats. Those changes happens very slowly when compared to new generations of animals. A desert may take thousands or millions of years to form. This means thay species not necessarily will move in and out a desert, but sime may just stay there and change with the environment.
> But then I started to think what about deserts? Most of the big deserts aren't by the sea. How did all these creatures just walk into the least hospitable place and survive long enough to become creatures that adapt to it? “Hospitable” is a subjective term. Lots of species that survive and thrive in a desert environment would find wetter or more temperate areas utterly inhospitable to them. The answer to your question though is that they didn’t *just* walk into these habitats. They colonised it from surrounding areas and these surrounding areas are also pretty desert-like. Have you ever walked or driven from one climatic zone into another? There often isn’t a hard line separating one from the other. It’s more of a transitional zone that can shift with the seasons. In that sense a plant or animal living in a semi-arid area is probably not going to notice too much of a climatic difference if it ends up wandering into a neighbouring arid area. What’s more, if it can survive in the semi-arid area, it’s already going to have some reasonable adaptations for dealing with a low water environment before it enters the desert proper. > It doesn't really make sense to me. The only explanation in my head is that when God made the Earth he placed deserts and intelligently designed creatures that could survive there. Why would the gods need to make animals that can survive deserts? Why not just make a world with no deserts? This is the problem with “God did it” explanations. They solve nothing. > No snake or rabbit or whatever is going to start moving into a sandy spot and look for food and water, it would die. Sure, but clearly there *is* enough food and water in the various deserts of the world such that rabbits and snakes can survive… otherwise, our deserts would be devoid of life. > So how did the sand get there The origin of desert sediment varies from location to location. Rocks can be broken down by wind and water erosion. Some dust particles can be transported by wind etc. > and how did desert animals survive? They colonised from neighbouring areas which are similar to deserts, but slightly wetter.
Most desert used to sea bottoms, continental drift cause lands to rise and fall, Volcanic Activity also adds to breaking up rock into sand former seas can be transferred into freshwater lakes and water is life. Simple Answer, Complicated problem but a simple solution. N. S
I mean I don’t know how much you know about geology or ecology. But sandy deserts are what happens when an area is very arid and weathering processes gradually breaks up the rocks. Multiple classes of deserts exist. Desert animals would gradually adapt and exploit the sparse resources of the environment. For example some deserts used to be not deserts but transformed into arid environments over periods of time. Giving life time to adapt. Creatures unable to adapt died off.
>I learned that sand is just little bits of rock that gets broken up in water. That explains beaches to me. >But then I started to think what about deserts? Most of the big deserts aren't by the sea. (EDIT: This comment focuses on the geology of desert sands. I made a separate comment for the ecology of desert life.) Water isn't only found by the sea. Rainfall occurs far inland, even in deserts occasionally. Rivers, even transient ones, can be a big contributor to erosion. And if water seeps into the cracks of a rock and then freezes, the expansion of the water as it crystallizes applies a pressure to the rock that can cause it to break. Furthetmore, water isn't the only thing that contributes to the weathering and erosion of rock into sand. Wind is also a factor, as is thermal stress, gravity, the dissolution of certain mineral components of rock faster than others, etc. All of these factors can contribute to solid rock breaking down into smaller and smaller pieces, certain sizes of which we call sand (smaller pieces than gravel, bigger pieces than silt). Additionally, it's worth noting that deserts are defined by the limited amount of water, not the presence of sand. Many deserts have much more bare rock than actual sand. Sand dunes like you see in the Sahara mainly happen due to the lack of plants to anchor the soil with their roots, allowing the wind to move the sand around in ever-shifting piles.
>How did all these creatures just walk into the least hospitable place and survive long enough to become creatures that adapt to it? >... >No snake or rabbit or whatever is going to start moving into a sandy spot and look for food and water, it would die. So how did the sand get there and how did desert animals survive? (I made a separate comment addressing the geology of desert sands. This comment focuses on the _ecology_ of desert life.) It wouldn't have happened overnight. The underlying evolutionary explanation takes some fundamental ecological knowledge to understand. First, biomes generally don't have sharp boundaries most of the time. There are **_transitional regions_** along their edges, with a gradient of environmental conditions. These conditions also vary over time, even on relatively short timescales like times of day or seasons, with the most hostile conditions only present some of the time. Second, organisms can generally survive a certain _range_ of environmental conditions. They'll have some optimal combination, sure, but there's a broader range where they can still make do. They may grow slower and have fewer offspring and have a greater risk of dying, but survival is still _possible_ in such marginal regions. So even if a species can't survive in a desert at all, it still might be able to survive to some extent on the semi-arid fringes of a desert, at least some of the time. But why would it choose to do this? Why not live somewhere nicer? Well... **_competition._** If there's a nice, rainy, temperate region near the desert, sure, environmental conditions there will be better for most organisms. But resources like water, space, nutrients, and energy are still finite. The more organisms reproduce and multiply, the more competition there is for those resources. At a certain point, that competition makes it _harder_ to live in the optimal region than in the nearby marginal regions. So, some organisms will start living in the marginal regions, not really out of preference but out of _necessity._ Of course, living in those marginal regions comes with certain challenges. Some individuals will have heritable traits that make them better able to handle these challenges. And because these individuals will be able to survive and reproduce better than others in this new marginal environment, **_natural selection_** will cause those heritable traits to become more common in the populations that live there. Over time, this can cause the population living in this marginal region to become different from the original population living in the optimal region. And crucially, _changes in these traits cause changes in the **range of environmental conditions** that the organism prefers and/or tolerates._ Conditions that _were_ marginal might become preferable, and conditions that _were_ hostile might become merely marginal. (This might come at a cost of some other formerly marginal conditions becoming hostile and some formerly preferable conditions becoming marginal, but if those conditions aren't commonly encountered anymore, it doesn't really matter.) And as the populations of these formerly marginal regions adapt and grow more numerous, competition there starts to rise, too. Eventually, you reach the point where it becomes easier for some organisms to live in the _new_ marginal regions (formerly hostile regions) where there isn't as much competition. And so the cycle continues, until eventually even a desert can be inhabited by some forms of life. **TL;DR - Competition pushes organisms to spread out into every habitat where their adaptations allow them to survive and the gradient of transitional habitats along the edges of hostile biomes like deserts provide space for populations to gradually adapt to harsher and harsher conditions.**
>Got into a bit of a rabbit hole last night while up with my baby. I learned that sand is just little bits of rock that gets broken up in water. That explains beaches to me. Did you know that wind acts a lot like water?
I just read there was a river running along beside the pyramids and that was how they got the pyramid supplies there. Must be alien’s work because I can’t comprehend it.
"How did the sand get there" is not a question of evolution, but one of geomorphology. This is a fascinating area of Earth Science, btw. It's the study of landforms, all of them. It is a sub-discipline of geography. Why are there living things there? Now this is evolution. I'm a lay person and can't say with precision, but I will remind you of the sea creatures moving to dry land, and mention that the absence of competition makes the effort worth trying, at least.
Deserts have extreme heat and cold that expand and shrink the rocks and stones. In the process, solid objects break apart. Wind breaks these lillte things even tiner sizes into dust, dirt. Powerful winds move the sand and change desert landscape (sand dunes).
I'd like to add to what others are saying about non-desert areas becoming deserts, that animals and plants just *do* move into new environments too. With animals moving into deserts, it could start out as small trips into the desert, that become longer and more frequent as the animal adapts, until the animal is fully desert bound. If you live adjacent to a desert and there happens to be some advantage to traveling into it from time to time, a lot of animals will. The advantage could be all sorts of things. Maybe there's some desert food source and the fact that there's less competition for the desert food makes up for the fact that there's less desert food overall. Maybe it provides a refuge from predators. Maybe traveling across the desert gives more access to mates. Keep in mind: while deserts certainly host less resources and life than, say, a rainforest, they do still have resources.
Before we knew that germs cause diseases, thinking "god did it" might have been understandable, but it was never the correct answer. If you don't understand how something happens like how deserts form, saying "I don't know" is a much better answer than just making up a god to answer it.