In my biology class, a girl proclaimed that humans were slowly “devolving” back into the pre-humanoid form. She was widely ridiculed, but is there any evidence or credibility to her theory?
No.
You should have thrown your feces at her.
Uhm, thanks for the in-depth answer?
Well that would prove her theory, wouldn’t it? 
While howling.
Not sure what other answer is possible. The idea has no evidential support, no scientific basis and is just plain silly. The only possible answer is “No, the theory has no evidence or credibility”.
She might just as well have propose that frogs are evolving wings so they don’t bump their arses on the ground when they hop. Actually, that is slightly more sensible than her suggestion.
NASCAR & pro bowling proves nothing.
In fact, recent evidence seems to support the hypothesis that humans now are evolving faster than ever, partially because of our (relatively recent) explosive population growth and correlated migration into new territories with new climates to adapt to.
However, if those findings don’t bear out, it may be the case that we are in some sort of an evolutionary equilibrium, i.e. a state with little (to no) selection pressure – beneficial mutations are not strongly favoured, and detrimental mutations not strongly selected against, as long as their effect isn’t too overwhelming (think, for instance, of poor eyesight – can get you killed in the wild, becomes wholly irrelevant in a civilised setting where glasses are readily available). The dominant mechanism for genetic variance within a population then isn’t natural selection any more, but rather genetic drift, which basically means that genes are distributed randomly among offspring, without either of them gaining any substantial (dis-)advantages. This lacks the ‘adaptive direction’ of evolution, but may, over time, increase the genetic variance within a population. Some might construe this as being a sort of ‘devolution’, however, it’s got nothing to do with changing back into primates.
It’s the girl’s proposal, so the proof is up to her not us. I doubt anybody on the board will agree with her and try to prove it is based on actual documented facts.
Is there significance to her ‘proclaiming’, rather than ‘nervously throwing out a wild idea’?
Was it religious?
Did she offer any support for her theory?
“God told me.”
“Based on a study, the theory could be tested by this research.”
There is no such thing as “devolution” (unless you’re talking about geographical politics of course). Evolution isn’t separated into distinct stages which can be “regressed” to, it’s just a constant unpredictable change. It’s improbable from a purely statistical point of view that we’ll continue to evolve in such a way to resemble our ancestors (although it can happen, for example some species of bat have re-adopted their ancestors’ burrowing habits). Feel free to laugh at the young lady in question with confidence.
Cite.
Not doubting you, but I’ve never heard of a burrowing and this sounds interesting.
Well it’s not burrowing in the sense that they live underground. IIRC they still live in caves but search for food by diving into and crawling around the organic detritus of nearby forests. Its been a while but I saw it on a wildlife documentary of some sort.
Give me a moment and I’ll try and google it.
Here we go;
Crawling bats: Mystacinidae - Wikipedia
Their ancestor: Icarops - Wikipedia
Oh those. They’re just New Zealand long ears. They also scavenge carrion, drink nectar, catch birds and eat eggs. That’s what happens when a mammal gets loose in an environment with no other mammals. So many unexploited niches, so little time to evolve. So they exploit multiple mammalian niches with a largely unmodified body plan.
One could argue that because of modern medical care, people who formerly (100,1000 yrs ago) would not have survived to reproduce are, in fact, now surviving to have kids of their own, thus passing on their craptastic genes future generations.
However, to suggest that we are regressing to a particular “pre-humanoid” form is to suggest that there are particular environmental forces that are causing our DNA to evolve in a particular direction, and I don’t think that’s the case. Quite the opposite, the paragraph highlights the fact that environmental pressures have been relaxed, and a wider variety of human genotypes are now being passed on to successive generations.
I burrow my feet under the bed covers (especially when the cats are there, since they’re nice and warm). Does that mean I’m devolving into some kind of underground creature?
No, it means you’ve just found a better way to keep warm. Individual creatures don’t evolve.
Also, as I said; there’s no such thing as devolution.
Anyway, 10:30, the other night, I go out in my yard, and there’s the Wurster kid, looking up in the tree. I say, ‘What are you looking for?’ He says ‘I’m looking for my burrow bat.’ I say, ‘Jumping Jesus on a Pogo Stick. Everybody knows the burrow bat lives. In a hole. In the ground. Why the hell do you think they call it a burrow bat, anyway?’
Do you think a kid like that will know what the Spudboys are doing to our soil?