I’ve been doing some learning about human pre-history and one question I have is what made humans only evolve in Africa? I know there were other hominid groups like Neanderthals and Denisovans but I don’t know as much about them. Did some of the other hominid groups spring out of other parts of world independently but just didn’t make it through the evolutionary arms race or did all hominids come out of Africa. If so, why? When lots of animals seem to have developed independently into similar ways like the different types of anteater type animals. I’m coming at this from a perspective of just liking to learn about human history and pre-history. The science behind evolution isn’t something I’m versed in
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Think of it this way.
Why were you and your siblings only born from one mother? Couldn’t you be born from multiple?
As in, humans can have only one origin, and it just happened to be Africa. Since if another one has sprung up in Americas, they wouldn’t be human.
To a certain extent, that’s just where it happened to occur.
Part of the answer is simply, “great apes existed in this part of Africa.” It’s though that one of the main drivers of our evolution was the growing prevalence of grasslands in Africa.
As forests became less common, our arboreal ancestors adapted by relying more on bipedal locomotion. This allowed them to see over the grasses to spot predators and prey, and helped aid them in developing very efficient running and sweating.
Already being highly social and intelligent, their flexible shoulders and gripping hands that evolved for moving around in trees turned out to be extremely useful for tool use and throwing things.
It seems that we didn’t see creatures like us evolve elsewhere because places where the other great apes live remained forested.
You’re confusing convergent evolution with evolution.
Evolution is when things are descendent from an ancestor species. Chimps and humans have a shared ancestor but evolved down different niches. We share traits with Chimps because we have a shared ancestor and evolution is conservative. It doesn’t really delete things, just adding.
Convergent evolution is that a shared characteristic is advantageous for multiple species, regardless of their origin; they develop a similar tool because of similar behavioral patterns rather than shared origin.
being homo sapiens-like is not the end goal of all hominids. it’s just how it went for us. looking at our evolutionary cousins, we see things like paranthropus, who went in their own evolutionary direction. there is a theory that homo floresiensis descended from asian homo erectus, but it lacks proof yet
As the other guy said. Your confusing how we define the evolution of animals and place them on the evolution tree.
Humans and Neanderthals both came from the same shared ancestor. That’s why we both have the homo pre tag on our species name.
The best shared ancestor I know of is Homo heidelbergensis. This means that this forbearer was spreading around the world at its own pace and at different times separated into different branches of homo. Ours separated in Africa and Neanderthals somewhere in Europe.
These separations likely happened because of different environments demanding different adaptations and promoting better breeding to people with the right mutations.
It’s not like we just popped up randomly in Africa, our adaptations were the best in that time and location. We could not have formed as homo sapiens unless we were part of the homo family.
Modern Humans and Neanderthals evolved from the same parent species, Homo heidelbergensis (Hh). Modern Humans evolved from them in Africa, while Neanderthals evolved from them in Europe and Asia. We don’t know much about Denisovians yet (or even if they are their own species!), but they likely evolved in Europe and Asia as well. Where Hh evolved is currently debated; the evidence points more toward Africa than Eurasia, but not conclusively so.
So it’s inaccurate to say that “humans” only evolved in Africa unless you are very specifically talking only about Homo sapiens.
The most accurate thing we can say is that Hh was a badass species that evolved in many different ways, but that one of those ways in particular out of northeastern Africa would eventually become dominant, leading to the eventual replacement of the others.
Australia and the Americas did not see hominid evolution but Africa, Europe, and Asia were just teeming with different versions of us, once upon a time.
The hominid family of great apes evolved in Africa.
Around 2 million years ago, groups of Homo Erectus began migrating out of Africa, into Europe and Asia.
They continued to evolve. In Europe they became Neanderthals. In Africa, some of them became Homo Sapiens.
Around 100 to 200 thousand years ago, Homo Sapiens began to migrate out of Africa again. Wherever they went, they competed, and in some cases interbred, with the other hominids they met. And the rest is history.
A single species does not independently evolve in different places.
One species may migrate to different places and then diverge into multiple species. For example, the various species of New World monkeys are descended from African monkeys that migrated to South America some 40 million years ago.
Different species may also independently evolve into similar forms and roles, despite not being directly related. For example, the echidna in Australia has some similarities to anteaters in South America, but those traits evolved independently.
In the case of hominids, we all descend from a common ancestor that split from chimpanzees some 6 million years ago in Africa. Since then, the hominid family emerged around 3 million years ago and split into a variety of species, many of which migrated out of Africa at various points in time.
Homo sapiens, the only surviving hominid species, likely emerged in the horn of Africa some 300,000 years ago. There were likely a number of early migrations out of Africa which mostly died off or retreated back. It is believed that present-day humans living outside of Africa all descend from one major migration around 70,000 years ago.
That homo sapiens only evolved in Africa isn’t as significant as that they out-competed all the other hominid species once they began to spread and encounter them, and they spread very fast.
The simplest answer for how and why anything evolves is that a member of a species acquired a trait due to a random mutation, that mutation was either beneficial or not detrimental to
survivalreproduction, and it was passed on.If you like, it’s not that no one else could have evolved big brains, it’s just that homo sapiens got big brains first and killed everyone else before they could get big brains.
Think of evolution like a chain. Each human has a parent who has a parent who has a parent, and they’re all connected. In human evolution, everyone’s chain links all the way back to Africa. If you go even further, the chains of all great apes link back to the same point as well.
So why didn’t we evolve elsewhere? Or anything close to us evolving elsewhere? To make an extreme point, the same reason your parents don’t have any kids on mars. Your parents have never been to mars, so you don’t have any Martian siblings.
But if your parents travel to mars and have kids and they have kids who have kids, now you have two populations of humans evolving in parallel.
This is how we got species like Neanderthals and homo floresiensis (hobbits). Common ancestor left Africa and moved around all over the world, allowing species to evolve in different places in parallel to each other. Yet all of them still trace their ancestors back to Africa