Robert Sapolsky | 1:19:28
Push off into new terrain here yet another bucket. But before doing that various bits of feedback from Office Hours hearing from TAS getting a sense of where the grand gaping craters of confusion are so far, and apparently an awful lot of them were provided in the last few days of lectures with behavior, genetics, various issues that came up, clearly one of the most complicated, inaccessible subtle pain in the neck concepts in the whole class, which is this heritability business.
So memorize the following two sentences, because it all comes down to the difference between something that is inherited, and how heritable a trait is. The fact that humans overwhelmingly have five fingers reflects the fact that the number of fingers is an inherited trait. The fact that when there are some circumstances of humans having other than five fingers, it is overwhelmingly due to environmental something or others is an indication of the fact that nonetheless, very ability around the number of five fingers heritability is essentially 0%. So get those two sorted out, and you have those two concepts all under your belt, and very useful. Why is it useful?
First off, why is this one useful? Because it is important to know the distinction, everybody, for one thing out there tends to view these is telling the same thing. And insofar as they think it says the same thing, they think that both terms are referring to this, something that is genetically regulated, genetically determined, whatever, two totally different terms.
So one reason to obsess over this is that when the newspapers give us our sound bite of scientists report that it's usually this one that they're reporting with one of those marvelously misleading numbers, which then sets people up for thinking they've just been told, how much do genes determine some average feature of this trait, so important to tell them apart? The other reason of getting this sorted out is not only to unlearn the nonsense aspects of misinterpreting this term, but because understanding that term gives you a lot of insights into when and how you are getting gene environment interactions. caveat with that, saying when and how you're getting gene, you're always getting gene environment interactions.
Remember the quote from the other day, it's like saying, which contributes more to the volume of a square or the height or the length of the randiness or whatever? Yes, it's always gene environment interactions, saying, In what ways are there some of the more interesting ones, dramatic ones, in what realms understand this, and you avoid this confusion, understand this, and it gives you insights into gene environment interactions, okay, other issues that are coming up.