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Gtronns t1_jdurnmt wrote

Reply to comment by jlpulice in Why are nonhuman erect bipedal animals so rare? by violetmammal4694

Ive heard that as the climate in africa changed, the trees receded from the region, but we stayed put.

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jlpulice t1_jdus9q8 wrote

I’m a PhD candidate in biomedical sciences, but people I’ve met in human evolutionary biology feel extremely confident the switch to bipedalism was about energetics of long distance travel. May be due to that too but it’s a walking thing!

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Gtronns t1_jdutbga wrote

Yeah, the idea was that once there were no more (significantly less) trees, we had a lot of walking to do. My point though, is that the trees left us, not us leaving the trees.

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Jonah_the_Whale t1_jdvqefw wrote

I don't understand. What about the vast herds of migrating quadrupeds? They seem to manage pretty well.

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[deleted] t1_jdvr7mz wrote

[removed]

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Krail t1_je2qpqb wrote

Those herds of migrating quadrupeds evolved from land-based quadruped ancestors, like most mammals. They already had an effective mode of locomotion for their environment that could develop and become more refined.

Our most direct ancestors were tree dwellers, with hands for hands and hands for feet, with hands and feet that were both built for gripping branches, and shoulders and hips that were both built for climbing and swinging. So as our ancestor's environment became less tree-dense, we came from a very different starting point that animals that were already quadrupeds.

For whatever reason, it was more advantageous for our ancestors to develop bipedalism rather than returning to being quadrupeds. There are lots of factors here, and we don't know all of them. One very likely factor is that, we already had limbs adapted for grabbing stuff, and having two limbs free for holding and carrying things has proven to be extremely advantageous for us.

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AvcalmQ t1_jdwhsz6 wrote

This content makes my current state of endurance even more disgraceful

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Lonely-Description85 t1_jdw3xk7 wrote

In Northern Africa sure. The Sahara was once a jungle...you may have something there. I never thought about that.

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Gtronns t1_jdw5plw wrote

Exactly. There are some great theories out there by evolutionary biologists.

So the idea is that we adapted a long time into trees, then the trees receded, and we adapted to the ground.

Now that we had gripping hands, and feet that could walk us places, we started being able to shape our environment and our tools, which led to greater intelligence.

Combine all of that, leads to us spreading out. Humans that went borth to Europe adapted to the lack of sunlight evolved. The humans that went on to asia evolved differently, to their climate, and they were the ones that were the ones that kept migrating, until they got to the americas (land bridge from russia to alaska that was exposed when ocean water receded into the ice caps - ocean water evaporates, clouds flow over the continents, it snows/rains, that precipitation turns to ice and stays as ice, ie a glacier, thus leading to the exposed land bridge). There they kept migrating south. The evidence for this is found in similarities that asians and native americans share genetically.

TL;DR We evolved in trees, trees stopped growing where we were, we evolved for the ground, ground got dry, we evolved to travel. We traveled far while the oceans were low. Go humans!!

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Lonely-Description85 t1_jdw7lyh wrote

There is biological evidence, can't find link atm, that when our species first started to eat saltwater fish was when our brains' frontal and temporal lobes really started to develop. Our occipitals were already highly evolved from our ape ancestors. So as we started to initially travel along ocean and river lines, eating omega rich foods skyrocketed our cognitive development even more.

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Gtronns t1_jdw86h9 wrote

Yeah, ive heard some theories like that, basically we are hairless water apes.

Ive also heard that we made leaps and bounds intelligence wise once when we started cooking our food with fire. Some theories say that we started eating cooked food after scavenging the remains after a forest fire, and finding cooked meat. Hard to say what actually happened, but i find that one to be a fun one.

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Lonely-Description85 t1_jdw9g6x wrote

It would make sense, the smell of a well cooked deer from a forest fire might have engaged the hunger mechanism in our ancestors, I could get behind that idea.

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Gtronns t1_jdw9nex wrote

"Dammmmn tuk-tuk, what smells so gooooood?" grunts and points to brunt deer in response

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