Comment by vinceguidry | Hacker News Reader

Comment by vinceguidry | Hacker News Reader

The article makes a few generalizations about evolution that don't really hold up. The idea that evolution does not have agency needs to be re-examined in the light of the fact that animals themselves have far more agency than we realized.

To use the author's example, cheetahs may well have all decided as a group to run faster, in the sort of 'social learning' way that we're just now starting to really get a grip on. I mean, adaptations don't just happen, beings have to use their abilities, and then the cells will respond by getting thicker, stronger, more responsive. Think about lifting weights. If agency isn't responsible for evolutionary advantages, then what is? Random differences? Really?

Evolution is way more complex than we realize. Every year, we come across crazy things that happen in our own bodies that just totally blow our minds. Right now I think our broader understanding of how evolution works is hampered by the fact that we just don't know yet how genomes hold on to experiences and then pass them along to our offspring. So we assume that every life form is a blank slate, limited to just the same genetic code all their fellow life forms share.

But just because we share the same template in one, specific way doesn't mean there can't be a ton of ways that fertilized zygotes can be different from each other too. And that those differences could result from the things our parents did in their lives.

"...we don't know how genomes hold on to experiences and then pass them along to our offspring. "

Err they don't. That's Lamarckism theory, and I wasn't aware there was even a shred of evidence towards it.

Sometimes when you don't know how something happens, its because it isn't actually happening

> Err they don't. That's Lamarckism theory, and I wasn't aware there was even a shred of evidence towards it.

There is quite a bit from the last few years. Gene expression in particular is a field we continue to learn a lot about [0] and several studies have suggested Lamarckism might have some merit [1].

Saying there isn't a "shred of evidence" is just scientifically untrue. There is some legitimate evidence that limited information could be passed from mother to child prenatally.

Your post is the classic Dunning–Kruger effect. Few in evolutionary biology would be as "sure" as you are, and you get less and less sure the more you learn.

[0] http://www.ncbi.nlm.nih.gov/books/NBK43787/ [1] https://en.wikipedia.org/wiki/Lamarckism#Epigenetic_inherita...

Macro-scale evolution does not go through epigenetics, but mostly "knob tweaks".

Because, why? Why exactly can't large scale evolutionary change by powered by single mother-child genetic signals? That makes just as much or as little sense as claiming that evolution is powered primarily through a single random mutation.

Actually, there has been some interesting demonstrating that epigenetic influences can affect gene expression in the offspring. Which isn't quite Lamarckism, but does imply some level of passing along experiences to the offspring.

Which isn't to say that the post to which you were replying didn't misunderstand what was meant by the word "agency".

I used to laugh at people who believed in an agency model and thought that humans were the "most evolved" (as opposed to fast breeding special like cockroaches, or for that matter cousins of ours like chimpanzees). I ascribed it to the hierarchical victorian world in which Darwin published (and the famous picture from that era of ape -> man). But of course it's ancient.

I had something I'd wanted to say but it got lost in the above post. I'm just now remembering what that was so I'll try again to explain it.

You don't actually need any information or experience to pass through to the next generation for behavior today to affect long-term evolution. Even if the only thing that's going on is that a population is using social learning to bring individuals closer to their genetic potential in one way, that way will be selected for in future generations. The genome itself could acquire adaptations during life, and those adaptations will then pass to their offspring. One would expect these 'mutations' to be really small, but add up quickly over successive generations.

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