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  • Toes are just so weird, I mean have you ever looked at them, theyre so stubby and useless,

  • why can’t we have cool grippy toes like chimpanzees?

  • Hey guys Julia here for Dnews. This little piggie went to market and this little piggie

  • is...well, it makes no sense. It looks like nothing else in the animal kingdom. Seriously.

  • have you ever just looked at your toes and thought why? Well, Hallo Pjotter asked us

  • how our toes evolved. And that’s a good question.

  • Toes likely evolved from the same bones that became fins, wings, or hooves in other species.

  • The dominating scientific theories are that fingers and toes are exclusive features of

  • tetrapods, or vertebrates with limbs. But according to one study, toes may have evolved

  • even before fish left the ocean. The study, published in the journal Nature, found 385

  • million years ago, a fish named Panderichthys, had homologous bones to our fingers and toes.

  • Either way, phalanges are over hundreds of millions of years old.

  • Human toes, specifically, are a little newer to the scene. Of all the other living primates,

  • were the only ones that exclusively walk upright on two legs. Other primates, like

  • chimps, have little grippy feet and ours are just kind of weird looking in comparison,

  • but research shows they used to be grippy back in the day. According to a study published

  • in the journal Foot and Ankle International, our ancestors Australopithecus afarensis,

  • which lived 3.5 million ago years ago, had feet that looked remarkably like a chimpanzee’s!

  • Fast-forward to homo habilis an ancestor who lived 1.76 million years ago. And her feet

  • looked a lot like ours do now. We traded in our opposable toe for shorter toes overall,

  • and gained an arch in our foot. What happened in that interim? Well in short, our ancestors

  • came down from the trees and started walking on land. As our foot evolved to support walking

  • on the ground, we started moving faster and faster, eventually learning to run. These

  • changes forced our feet to evolve to deal with both balance and propulsion in a highly

  • efficient way. Basically, our feet became more springy and shock-absorbent.

  • And there's a study to back this up in the Journal of Experimental Biology, showing basically,

  • these toes are made for running. The researchers created models which showed that longer-toed

  • individuals do more mechanical work to stabilize their joints and ligaments. This means they

  • use more energy to run the same distance as shorter-toed people.

  • This supports what’s called theendurance running hypothesisor the idea that our

  • ancestors were really good at running long distances in order to chase down and wear

  • out prey. In this kind of hunting style, those with long toes are evolutionarily selected

  • against because it takes them more work to do run down the same prey. The researchers

  • also found shorter toes might reduce the risk of injury meaning, long-toed people would

  • expend more energy to run the same distance, AND run a higher risk of injury while doing

  • it!

  • So, our toes, while short and stubby, maybe have evolved to help us run, keep our balance,

  • and absorb impact. So, the next time you go for a jog thank your toes, even though they

  • can’t help you climb trees anymore.

  • The weird thing though I keep hearing about toes, is that our pinky toe is going away,

  • that were evolving out of it. It’s just a useless vestigial structure. But that’s

  • more old wives tale than anything else. As for one of our other useless lumps left over

  • from evolution: the appendix, it might not be so useless after all, Tara has the whole

  • story, right here.

Toes are just so weird, I mean have you ever looked at them, theyre so stubby and useless,

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足の指はなぜこんなに変な形に進化したのか?#進化した足の指はなぜこんなに変に見えるのか? (Why Did Our Toes Evolve To Look So Weird? #AskDNews)

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    陳叔華 に公開 2021 年 01 月 14 日
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