Why only "out of Africa?"

[EWyatt]

My first posting in this forum, so....

The consensus is that humans (sapiens) slowly made their way out of Africa around 100K years ago (or so) and eventually populated the Earth.  Considering that mammals survived the KT extinction around 66 MYA and were present worldwide, why wouldn't they evolve likewise throughout the planet, as they did in Africa apparently.  Or perhaps they did (though I haven't read about it) considering the many different "races" in the world today.  Why would Africa be the only sweet spot?  Or could it be that there WERE other Homo "evolutions" worldwide, but natural selection edited the others out somehow and left Africa as the only birthplace of Homo Sapiens. 

This may be an over-simplistic question, but it's all I've got for now.  Help!

 

EW

[Itoero]

The reason why we  developed/evolved in/from Africa is because the 'apes' we evolved from, lived in Africa.

Other monkeys/apes simply did not evolve into humans.

Here you find a list of many fossils they found concerning human evolution and a lot of info: https://en.wikipedia.org/wiki/List_of_transitional_fossils#Human_evolution

 

Edited August 14, 2018 by Itoero

[Ten oz]

It is believed that human life initially evolved in Africa but many animals evolved elsewhere and continue to. Even types of humans evolved after leaving Africa. Neanderthals (which were human) evolved to become Neanderthals in Eurasia for example. Evolution doesn't have a "sweet spot". 

[mistermack]

The OP is fairly typical of how a lot of people see evolution. They think it had a purpose, and that purpose was us. It's a fundamental misunderstanding of what evolution is and what it's for.

There is no purpose to evolution. We humans are not the desired final product. And so there is no "sweet spot". Africa isn't a sweet spot. It's just a spot. 

Take away humans, and Africa is no sweeter than anywhere else. It's not about a place. It's about a line of apes that took a different direction. Or to be more accurate, directions, as there were a lot of slightly different species before our own line. Just as there are bonobos and chimpanzees, our ancestors split into several different lines.

[EWyatt]

21 hours ago, mistermack said:

The OP is fairly typical of how a lot of people see evolution. They think it had a purpose, and that purpose was us. It's a fundamental misunderstanding of what evolution is and what it's for.

There is no purpose to evolution. We humans are not the desired final product. And so there is no "sweet spot". Africa isn't a sweet spot. It's just a spot. 

Take away humans, and Africa is no sweeter than anywhere else. It's not about a place. It's about a line of apes that took a different direction. Or to be more accurate, directions, as there were a lot of slightly different species before our own line. Just as there are bonobos and chimpanzees, our ancestors split into several different lines.

Sorry for simply being "typical," which explains the reason I asked.  I only wanted others' opinions.  But being atypical, you supplied an answer that makes sense: that those African apes took a different evolutionary direction from all the other apes in the world.  And that surely doesn't make their homeland a sweet spot.  Oh no.

EW (they)

22 hours ago, Itoero said:

The reason why we  developed/evolved in/from Africa is because the 'apes' we evolved from, lived in Africa.

Other monkeys/apes simply did not evolve into humans.

 

A good, solid answer,  Thanks.

The next question could be: why didn't other apes evolve as he Africans did.  Environment, chance, slight genetic differences... etc?  But I'm afraid to ask, here.

[Ten oz]

55 minutes ago, EWyatt said:

The next question could be: why didn't other apes evolve as he Africans did.  Environment, chance, slight genetic differences... etc?  But I'm afraid to ask, here.

Genes mutate. Everyone, all animals, have mutations. Those mutations range from benign to causing severe disabilities. Under good conditions where a population is thriving there is enough genetic diversity within a species that single mutations are not bred for generations. When something in the environment, natural or artificial, limits reproduction and only those with specific mutations are able to reproduce that is when species begins to diverge. Often a species just goes extinct when environments change enough to impact reproduction. Sometimes enough individuals in a species hang on due to a mutation they have which enables them to make it, reproduce, and continue on. That is how Natural Selection works. When all is well and reproduction is healthy species generally stay the same with limited change on millenia.

If a species of ape didn't evolve it is because it didn't need to.

 

[Itoero]

There must have been many 'things'  that allowed for example the evolution of bipedalism and our kind of intelligence. Biological evolution is about adapting to a changing environment. The environment in Africa was obviously very favorable for human evolution.

Edited August 15, 2018 by Itoero

[CharonY]

2 hours ago, Ten oz said:

If a species of ape didn't evolve it is because it didn't need to.

There is little, if anything that does not evolve during sufficiently long time frames.

[Ten oz]

31 minutes ago, CharonY said:

There is little, if anything that does not evolve during sufficiently long time frames.

Of course. My post was meant to be simple. Those who do not understand evolution do not recognize the differences between Chimpanzee and Bonobo. They see Human as some massive leap which evolution can't account for. 

[mistermack]

3 hours ago, EWyatt said:

Sorry for simply being "typical," which explains the reason I asked.  I only wanted others' opinions.  But being atypical, you supplied an answer that makes sense: that those African apes took a different evolutionary direction from all the other apes in the world.  And that surely doesn't make their homeland a sweet spot.  Oh no.

Again, you are posting from a position of little understanding of evolution. It's not unusual for species to take different evolutionary paths. You could just as correctly say that it was the other apes took a different evolutionary direction to us. And it was the rest of the world that was the sweet spot. Why do you pick Africa as the sweet spot? There was an Asian ape that stood ten feet tall, and weighed up to half a ton. 

The answer is that you are making the wrong assumption that we are somehow special. To us, yes we are. To evolution, we're just another ape. 

Actually, Africa WAS a sweet spot for apes, tens of millions of years ago. The recent history of apes has been of decline from a golden age. The general opinion is that apes have been losing out competitively to monkeys, who can eat fruit when it's unripe, that would give us and other apes a bad stomach. 

[zapatos]

3 hours ago, mistermack said:

Again, you are posting from a position of little understanding of evolution.

Perhaps we should aim for simply answering questions and increasing understanding without the observations about a person's relative ignorance on a particular subject.

[swansont]

16 hours ago, EWyatt said:

Sorry for simply being "typical," which explains the reason I asked.  I only wanted others' opinions.  But being atypical, you supplied an answer that makes sense: that those African apes took a different evolutionary direction from all the other apes in the world. 

What other apes in the world? Where did apes exist, outside of Africa, when the human lineage began splitting off?

[mistermack]

9 hours ago, zapatos said:

Perhaps we should aim for simply answering questions and increasing understanding without the observations about a person's relative ignorance on a particular subject.

Well, I was replying it that case to a sarcastic post, so why not? 

It's too tempting, if a post is sarcastic AND on the wrong track. Anyway, I really don't mind, if someone points out my own lack of knowledge on a subject. (which happens a lot) It's not good for the ego but it's an incentive to look stuff up. 

1 hour ago, swansont said:

What other apes in the world? Where did apes exist, outside of Africa, when the human lineage began splitting off?

There are Orang Utans and lots of Gibbons in Asia, and there was the extinct Gigantopithecus that I mentioned earlier. So their ancestors would have been around. Probably others too I imagine. 

[Sensei]

29 minutes ago, mistermack said:

There are Orangutans and lots of Gibbons in Asia, and there was the extinct Gigantopithecus that I mentioned earlier. So their ancestors would have been around. Probably others too I imagine. 

How about extending question to "where did monkey exist, outside of Africa,  ...."?

Howler monkey and few others in Central and South America..

https://en.wikipedia.org/wiki/New_World_monkey

Macaque in North Africa (Morocco) and Asia, including Japan islands.

 

 

Edited August 16, 2018 by Sensei

[mistermack]

10 minutes ago, Sensei said:

Howler monkey and few others in Central and South America..

https://en.wikipedia.org/wiki/New_World_monkey

Macaque in North Africa (Morocco) and Asia, including Japan islands.

Those are all monkeys though, not apes.

[Sensei]

2 minutes ago, mistermack said:

Those are all monkeys though, not apes.

And so what? If apes in Africa would not evolve to humans, they could evolve to "apes v2.0" and later to "humans v2.0"..

Japanese monkeys started catching and eating fishes. That's quite good start. Predators require bigger brain to predict behavior of prey.

https://www.japantimes.co.jp/news/2016/02/03/national/year-miyazaki-islands-fish-eating-monkeys/

 

 

[mistermack]

16 minutes ago, Sensei said:

Predators require bigger brain to predict behavior of prey.

That doesn't follow. Eagles eat monkeys. Sharks eat seals and dolphins. Crocodiles kill people. Snakes eat monkeys and apes. It's not really a rule that predators require a big brain. 

[Sensei]

33 minutes ago, mistermack said:

That doesn't follow. Eagles eat monkeys. Sharks eat seals and dolphins. Crocodiles kill people. Snakes eat monkeys and apes. It's not really a rule that predators require a big brain. 

What I meant was that if they would continue catching fishes, generation by generation, their brain would evolve bigger and bigger, as evolution would promote individuals with bigger brain, as they would more easily catch prey and have more offspring.

BTW, you should compare e.g. eagle brain size with pigeon brain size, etc. at least in the same division of animals. Your examples are not their staple food, just accidental (except sharks and seals). Sharks have bigger brain than seals.

 

Edited August 16, 2018 by Sensei

[zapatos]

1 hour ago, mistermack said:

Well, I was replying it that case to a sarcastic post, so why not?

Yeah, sorry. I tried to delete my post but I waited too long.

[swansont]

58 minutes ago, Sensei said:

And so what?

Because we are descended from apes, not monkeys.  

1 hour ago, mistermack said:

 There are Orang Utans and lots of Gibbons in Asia, and there was the extinct Gigantopithecus that I mentioned earlier. So their ancestors would have been around. Probably others too I imagine. 

The next step is to make the argument that they were candidates for evolving into bipedal, large-brained creatures with opposable thumbs, while being further removed from the apes that actually did give rise to humans, while living in the environment that they did.

That applies to the argument about monkeys, too.  

 

 

[iNow]

5 minutes ago, swansont said:

Because we are descended from apes, not monkeys.  

Slight picked nit. We ARE apes, and we share common ancestors with other apes.

I know you’re well aware of this already, it just didn’t come through in the way you wrote this and I’m feeling pedantic for some reason. 

[swansont]

Just now, iNow said:

Slight picked nit. We ARE apes, and we share common ancestors with other apes.

I know you’re well aware of this already, it just didn’t come through in the way you wrote this and I’m feeling pedantic for some reason. 

Yes. We are apes descended from other, older ape species. The point being that if you pick a different ancestral group, you have a harder time coming up with a scenario where they would have evolved into human-like creatures. They evolved along the path they did for a reason (many reasons, in fact), and did not evolve along alternate paths for reasons.

Taking the discussion to a more absurd level, one could ask why some ancestral line of frogs didn't give rise to a human-like species. The general answer would be similar — how do you get along that path of steps of creatures which are adapted to their environment, with the features you are looking for? e.g. why would they become bipedal? What advantage does that give?

Take mistermack's mention of Gigantopithecus. Why would a species that might have been 3m tall develop bipedal locomotion? How would you support the weight of a 400-500 or perhaps 600 kg creature?  Which means that the answer is very Willie Sutton-like (and someone already pointed this out): they came from Africa because that's where the species were that would have given rise to humans.

 

[mistermack]

We humans really are freaks when it comes to intelligence. But it doesn't mean that there's anything special about Africa. It happened there, and didn't arise elsewhere, so it's obviously a unique combination of things peculiar to Africa. I suppose you can regard that as special if you like. But only in the sense that everywhere is special in it's own way.

Africa happened to be the home of our ancestor that gave rise to us, chimpanzees and gorillas. So it wasn't so special that we HAD to evolve as we did. Like the rest of evolution, it's down to chance.

What's definite, is that our own line firstly became bipedal, a long time before there were clear signs of a bigger brain. But after that, we did eventually started evolving the big brain, and the chimps and gorillas did not. So it was something about the lifestyle of bipedal apes that gave rise to more intelligence. There are various ideas about that, but no real consensus. The only thing you can be sure of, is that the more advanced intellectually were surviving in bigger numbers than the more primitive, over millions of years. 

So really, it's likely to have been behaviour, and not the location, that put us on the road to the present. Chimps and Gorillas and Bonobos did perfectly well in Africa, without needing to evolve a bigger brain.

 

[Itoero]

4 hours ago, mistermack said:

What's definite, is that our own line firstly became bipedal, a long time before there were clear signs of a bigger brain

That's logic but do you have evidence for this?

I've read that our intelligence probably as a means of surviving and reproducing in large and complex social groups evolved. https://en.wikipedia.org/wiki/Evolution_of_human_intelligence

 

 

[mistermack]

25 minutes ago, Itoero said:

That's logic but do you have evidence for this?

I've read that our intelligence probably as a means of surviving and reproducing in large and complex social groups evolved. https://en.wikipedia.org/wiki/Evolution_of_human_intelligence 

It's in the fossil record. There were fully bipedal apes, that had brains comparable to modern chimpanzees. They date to five or six million years ago. If you search for australopithecus afarensis, or adipithecus ramidus, you will find loads of evidence. 

So it's solid fossil evidence of apes with modern human feet, not ape feet. Also, there are fossilised footprints from the same date, showing upright walking by the same feet. Search for Laetoli Footprints.

Complex social groups do encourage some intelligence, but there are plenty of monkeys and apes who live in similar groups. 

Edited August 16, 2018 by mistermack