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0 pointsthrowup2389mo ago0 comments

Here’s where it helps to have at least some background in biology: what you propose is not a radical hypothesis. In fact I’d be hard pressed to find a single neuroscientist who disagrees with that hypothesis except in its most nuanced details.

We have no idea how that information is transmitted from generation to generation but we have enough animal behavior research to know that many animals instinctually identify visual cues like predators pretty much from the moment they are born. We also have decent evidence that the inheritance may not be entirely genetic in origin, because nearly identical populations in different locales may have wildly different behaviors (like the animals in the Galapagos islands, who aren’t afraid of humans because they’ve had no predators).

The three main candidates for how this information is transmitted are: genetics, epigenetics, and embryonic development. The latter two fields are still in their infancy but that leaves more room for just so stories.

Always beware of anyone using evolutionary biology to make an argument about the development of species.

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xg159mo ago

That sounds entirely reasonable and also extremely exciting. I didn't know there is so much research on that topic going on. Thank you for explaining that.

> Always beware of anyone using evolutionary biology to make an argument about the development of species.

From what I understand so far, I can just say that I dislike arguments of the form "feature X provides evolutionary advantage Y to the species, and that explains why the species evolved it".

In fact, it doesn't explain anything: Being able to shoot laser beams out of ones eyes would provide a large evolutionary advantage, but I still don't expect any future children of mine to spontaneously develop that ability - because there is no feasible way how the body could change to realize that ability, how that change would be transmitted from the parents or how it would even develop in the first place.

I think it could still be a useful shorthand if you already know that an aspect of the body is influenced by evolution, to explain the "direction" this feature took.

But I think I see what you mean, there is a risk of getting caught up in "it could have happened like this" speculation that is not grounded in any reality anymore.

throwup238OP9mo ago

> But I think I see what you mean, there is a risk of getting caught up in "it could have happened like this" speculation that is not grounded in any reality anymore.

Almost but not quite. Evolutionary laser beams can be discounted out of hand but when we’re talking about a feature (phenotype) that already exists, it is somewhat grounded in reality because we have incontrovertible proof that it can evolve. That opens it up to wild speculation about convoluted evolutionary paths and, since 500+ millions of years of natural selection is nothing if not convoluted, very many of them sound very reasonable.

The added complication is that most of the evidence doesn’t exist anymore or is so degraded our current technology can’t recover the data. Figuring out the “direction” of evolution is nearly impossible because we have few intermediate genetic samples for organisms beyond ~500-1000kYa. The science of extracting DNA from recent fossils is also in its infancy.

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