I couldn’t find great explanations online, so here’s my explanation after a bit of Googling. I welcome corrections from real experts.
Organisms exhibit phenotypic plasticity when they act differently in different environments. The phenotype (manifested traits: color, size, etc) manifests differently, even though two organisms might share the same genotype (genetic makeup).
Panel 1: organisms are not phenotypically plastic and do not adapt to a spider-filled environment. Panel 2: a plastic organism might do the bad thing, and then learn not to do it again, increasing its fitness. Panel 3: genetic assimilation hard-codes important commonly learned lessons, cutting out the costs of learning.
The most obvious example of phenotypic plasticity is learning. Learning lets you adapt to environments where your genotype would otherwise do poorly.
The Baldwin effect is: evolution selects for genome-level hardcoding of extremely important learned lessons. This might even look like, the mom learned not to eat spiders, but her baby is born knowing not to eat spiders.
[disclaimer: not an expert, possibly still confused about the Baldwin effect]
A bit of feedback on this explanation: as written, it didn’t make clear to me what makes it a special effect. “Evolution selects for genome-level hardcoding of extremely important learned lessons.” As a reader I was like, what makes this a special case? If it’s useful lesson then of course evolution would tend to select for knowing it innately—that does seem handy for an organism.
As I understand it, what is interesting about the Baldwin effect is that such hard coding is selected for more among creatures that can learn, and indeed because of learning. The learnability of the solution makes it even more important to be endowed with the solution. So individual learning, in this way, drives selection pressures. Dennett’s explanation emphasizes this—curious what you make of his?
As a reader I was like, what makes this a special case? If it’s useful lesson then of course evolution would tend to select for knowing it innately—that does seem handy for an organism.
Right, I wondered this as well. I had thought its significance was that the effect seemed Lamarckian, but it wasn’t. (And, I confess, I made the parent comment partly hoping that someone would point out that I’d missed the key significance of the Baldwin effect. As the joke goes, the fastest way to get your paper spell-checked is to comment it on a YouTube video!)
curious what you make of his?
Thanks for this link. One part which I didn’t understand is why closeness in learning-space (given your genotype, you’re plastic enough to learn to do something) must imply that you’re close in genotype-space (evolution has a path of local improvements which implement genetic assimilation of the plastic advantage). I can learn to program computers. Does that mean that, given the appropriate selection pressures, my descendents would learn to program computers instinctively? In a reasonable timeframe?
It’s not that I can’t imagine such evolution occurring. It just wasn’t clear why these distance metrics should be so strongly related.
Reading the link, Dennett points out this assumption and discusses why it might be reasonable, and how we might test it.
The Baldwin effect
I couldn’t find great explanations online, so here’s my explanation after a bit of Googling. I welcome corrections from real experts.
Organisms exhibit phenotypic plasticity when they act differently in different environments. The phenotype (manifested traits: color, size, etc) manifests differently, even though two organisms might share the same genotype (genetic makeup).
The most obvious example of phenotypic plasticity is learning. Learning lets you adapt to environments where your genotype would otherwise do poorly.
The Baldwin effect is: evolution selects for genome-level hardcoding of extremely important learned lessons. This might even look like, the mom learned not to eat spiders, but her baby is born knowing not to eat spiders.
(No, it’s not Lamarckian inheritance. That’s still wrong.)
[disclaimer: not an expert, possibly still confused about the Baldwin effect]
A bit of feedback on this explanation: as written, it didn’t make clear to me what makes it a special effect. “Evolution selects for genome-level hardcoding of extremely important learned lessons.” As a reader I was like, what makes this a special case? If it’s useful lesson then of course evolution would tend to select for knowing it innately—that does seem handy for an organism.
As I understand it, what is interesting about the Baldwin effect is that such hard coding is selected for more among creatures that can learn, and indeed because of learning. The learnability of the solution makes it even more important to be endowed with the solution. So individual learning, in this way, drives selection pressures. Dennett’s explanation emphasizes this—curious what you make of his?
https://ase.tufts.edu/cogstud/dennett/papers/baldwincranefin.htm
Right, I wondered this as well. I had thought its significance was that the effect seemed Lamarckian, but it wasn’t. (And, I confess, I made the parent comment partly hoping that someone would point out that I’d missed the key significance of the Baldwin effect. As the joke goes, the fastest way to get your paper spell-checked is to comment it on a YouTube video!)
Thanks for this link. One part which I didn’t understand is why closeness in learning-space (given your genotype, you’re plastic enough to learn to do something) must imply that you’re close in genotype-space (evolution has a path of local improvements which implement genetic assimilation of the plastic advantage). I can learn to program computers. Does that mean that, given the appropriate selection pressures, my descendents would learn to program computers instinctively? In a reasonable timeframe?
It’s not that I can’t imagine such evolution occurring. It just wasn’t clear why these distance metrics should be so strongly related.
Reading the link, Dennett points out this assumption and discusses why it might be reasonable, and how we might test it.