# What is protein homology? **URL:** \ **Category:** Factual Questions\ **Created:** [August 7, 2000, 1:13pm UTC](https://boards.straightdope.com/t/what-is-protein-homology/28414 "2000-08-07T13:13:39Z")\ **Posts on this page:** 6\ **Page:** 2
**Author:** ![Ben](https://avatars.discourse-cdn.com/v4/letter/b/df788c/32.png) [@Ben](https://boards.straightdope.com/u/Ben)\ **Post date:** [August 9, 2000, 12:20am UTC](https://boards.straightdope.com/t/what-is-protein-homology/28414/21 "2000-08-09T00:20:19Z")
> [@](#): > > \*Originally posted by Myrr21 \* > \*\*Errr, did you read my post? \*\* Yes, but my post wasn’t a criticism of yours. I was just chiming in. -Ben ---
**Author:** ![Ben](https://avatars.discourse-cdn.com/v4/letter/b/df788c/32.png) [@Ben](https://boards.straightdope.com/u/Ben)\ **Post date:** [August 9, 2000, 12:24am UTC](https://boards.straightdope.com/t/what-is-protein-homology/28414/22 "2000-08-09T00:24:25Z")
> [@](#): > > \*Originally posted by LateComer \* > \*\*Two great thinkers who can explain the most esoteric science in language that High School kids can understand whil not talking down to anybody. \*\* What do you mean by “talking down”? I’ve heard it before, I have a vague idea what it means, but I’m not sure what, precisely, “talking down to the reader” consists of. -Ben ---
**Author:** ![wevets](https://avatars.discourse-cdn.com/v4/letter/w/e9a140/32.png) [@wevets](https://boards.straightdope.com/u/wevets)\ **Post date:** [August 9, 2000, 12:35am UTC](https://boards.straightdope.com/t/what-is-protein-homology/28414/23 "2000-08-09T00:35:15Z")
> [@](#): > > \*Originally posted by LateComer \* > Stephen Jay Gould and the late Isaac Asimov. Richard Dawkins is another author you might want to look into. ---
**Author:** ![Myrr21](https://avatars.discourse-cdn.com/v4/letter/m/e495f1/32.png) [@Myrr21](https://boards.straightdope.com/u/Myrr21)\ **Post date:** [August 9, 2000, 12:52am UTC](https://boards.straightdope.com/t/what-is-protein-homology/28414/24 "2000-08-09T00:52:01Z")
> [@](#): > > \*Originally posted by Ben \* > \*\* > > > [@](#): > > > > \*Originally posted by Myrr21 \* > > \*\*Errr, did you read my post? \*\* > > Yes, but my post wasn’t a criticism of yours. I was just chiming in. > > -Ben \*\* I was just curious…seeing as you \* did \* quote my post. Ahh well. 🙂 ---
**Author:** ![APB9999](https://avatars.discourse-cdn.com/v4/letter/a/8e8cbc/32.png) [@APB9999](https://boards.straightdope.com/u/APB9999)\ **Post date:** [August 9, 2000, 3:34am UTC](https://boards.straightdope.com/t/what-is-protein-homology/28414/25 "2000-08-09T03:34:26Z")
> [@](#): > > One more question, please. Does the protein sequence (the string of letters) change within a species over time? Yes. Any mutation that occurs in offspring will be passed on to that individual’s offspring (assuming of course that it is either a neutral or beneficial mutation). So that new sequence will come to prevalence in the species if, say, that particular hereditary line is the only one to survive a massive die-off. More likely it will come to prevalence through breeding: if more and more individuals carry that new sequence (through successful breeding), eventually it may characterize the whole population or species. It’s pretty obvious how this occurs with beneficial mutations, but it could happen with a neutral mutation, too: If that neutral mutation happened to occur in an individual who had some OTHER advantage/s, it could spread simply because kiddies get the whole packege of genes passed on from generation to generation, not just one gene at a time. And then, sometimes, it can just happen _by chance_ that a neutral mutation spreads through the population (low probability, usually, but on the evolutionary scale you could theoretically see it) Obviously, the above is a gross simplification of a very complex process, but I hope you can see the general picture. Protein sequences can change over time at every level: in individual hereditary lines, at the population level, at the species level, and at every taxonomic level above species. ---
**Author:** ![manhattan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/manhattan/32/7_2.png) [@manhattan](https://boards.straightdope.com/u/manhattan)\ **Post date:** [August 9, 2000, 10:30pm UTC](https://boards.straightdope.com/t/what-is-protein-homology/28414/26 "2000-08-09T22:30:58Z")
Gould, Asimov and Dawkins are all excellent suggestions. Can someone recommend a book or a chapter that directly addresses protein homology? [Previous page](https://boards.straightdope.com/t/what-is-protein-homology/28414.md?page=1)