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Comment by verve_rat | Hacker News Reader

> Animals don't have to learn to walk.

Have you seen baby deer?

A baby deer is standing within minutes of being born and walking later that day. I don’t think humans are in any position to insult a baby deer’s ability to walk. A human takes about a year and is also terrible at it when starting out.

Shouldn't humans have far longer gestation periods (due to it being born 'early' as it otherwise would not fit though the birth canal) and maybe that's the issue at fault?

It seems there are two different classifications for species when it comes to how mobile they are near birth and how much care the newborns need.

Deer are precocial, while humans are altricial.

https://en.m.wikipedia.org/wiki/Precociality_and_altricialit...

Yet without any external inputs, the deer will eventually learn to walk by itself, suggesting some kind of internal hardwiring.

I guess I don’t understand what you mean “with no external inputs”. It’s in the physical world, with gravity. Isn’t that an external input? Driving the feedback loop of “I fall on my face if I do it wrong”?

I think it's more a "if I fall I'm gonna get eaten/injured and not be able to reproduce" kind of thing

That falling on the face is irrelevant, as it's just a byproduct of some pre-determined programming that is not learned. Surely if this was a learned experience the deer after failing on its face would quickly learn it's best to not try and stand up. Why am I standing when I just keep hitting my face into the ground? The reality is the drive programmed into the brain is to stand up at all costs, even if that means landing flat on your face once in a while.

I guess in my mental model, the deer continues to try and stand because it wants to things like food and water, and it sees other deer standing and walking around. Psychologists do talk about a state of "learned helplessness" if a living creature fails too often.

I don’t know anything about the state of research here, this is just what I always assumed. I’m sure there are built in drives and reflexes, etc. It seems perfectly reasonable that they could be "higher level" than the ones I assumed (food, water)

Yeah, they "learn" to walk pretty quickly. Far too fast for it to be purely learning.

Animals that are ready to go shortly after birth are called precocial. This includes chickens and most of the equines.

If you've ever seen a newborn foal stand up for the first time, it's clear that's a built-in behavior. Standing up on those long spindly legs usually works the first time. So does walking, and within hours, running.

Lying down, however, is not built-in. I've seen a foal try to get back down on the ground, which is clearly trial and error, often ending in a fall. There's no evolutionary pressure to have that work right the first time.

Yeah but deer are legitimately bad at walking.

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