tag:blogger.com,1999:blog-11390444.post113702216517770095..comments2023-10-23T09:26:24.969-10:00Comments on The Questionable Authority®: Applications of Evolution 3 - tradeoffs in resistance.TQAhttp://www.blogger.com/profile/01510784510555073197noreply@blogger.comBlogger8125tag:blogger.com,1999:blog-11390444.post-1137380086662863272006-01-15T16:54:00.000-10:002006-01-15T16:54:00.000-10:00Interesting post. I hadn't heard of the West Nile ...Interesting post. I hadn't heard of the West Nile connection. If historically there have been other pathogens affected by this polymorphism, then the reason both variants are floating around at notable frequencies in our species could be due to balancing selection. Even "in North America just a few years back," the effects of this variant could have been a complex equation involving many germ Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-11390444.post-1137139340244409992006-01-12T22:02:00.000-10:002006-01-12T22:02:00.000-10:00Bob, I'm actually somewhat familiar with the Santa...Bob, <BR/><BR/>I'm actually somewhat familiar with the Santa Rosalia paper. My advisor has assured me that it will feature prominently in my oral comps down the line. <BR/><BR/>I did try to cheat just a little there, and slide by without mentioning assortative mating, purely in the interests of keeping things simple. (One of the problems I'm finding as I study speciation is that it's such a TQAhttps://www.blogger.com/profile/01510784510555073197noreply@blogger.comtag:blogger.com,1999:blog-11390444.post-1137088800311762152006-01-12T08:00:00.000-10:002006-01-12T08:00:00.000-10:00Speciation is complex. In the documentary The Wild...Speciation is complex. In the documentary <I>The Wild Parrots of Telegraph Hill</I>, two species of South American conures are able to hybridize and produce fertile offspring. Because these species are normally geographically isolated, the chance to mate doesn't normally happen. But for escaped parrots in San Francisco, the geographical barriers no longer exist. Give them a few hundred years, andAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-11390444.post-1137085378293218922006-01-12T07:02:00.000-10:002006-01-12T07:02:00.000-10:00OK, i had to look up assortative mating. The argu...OK, i had to look up <I>assortative mating</I>. The argument still doesn't follow. If you have a geographically isolated population, then some local environment change, like malaria, could easily push for changes in that population. Sure, it will take many such changes to create a new species, but that doesn't mean it won't happen. <I>Assortative mating</I> is impossible for asexual microbes,Stephenhttps://www.blogger.com/profile/03934169832326108710noreply@blogger.comtag:blogger.com,1999:blog-11390444.post-1137047135701144212006-01-11T20:25:00.000-10:002006-01-11T20:25:00.000-10:00"If the allele is helpful in some locations and ha..."If the allele is helpful in some locations and harmful in others, it can actually lead to a situation in which you get genetic differences in different areas of the population. That's cool, because it is one of the many scenarios that can lead to one species dividing into two."<BR/><BR/>This won't work, as Joe Felsenstein pointed, um, out 25 years ago:<BR/>Felsenstein, J. (1981). Skepticism Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-11390444.post-1137042320495366132006-01-11T19:05:00.000-10:002006-01-11T19:05:00.000-10:00I remember this principle from Biology II when we ...I remember this principle from Biology II when we talked about the C allele in the sickle-cell anemia gene. Genes ALWAYS act in the context of the environment; biology is never as simple as the IDers want to pretend it to be.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-11390444.post-1137027140630108462006-01-11T14:52:00.000-10:002006-01-11T14:52:00.000-10:00I'm not surprised that lacking CCR5 has a disadvan...I'm not surprised that lacking CCR5 has a disadvantage, because it's normally involved in sensing chemokine gradients. Without the receptor cells like macrophages, which normally process and transport antigens to effector cells of the immune system would get a little 'confused'. They still function but their function is still somewhat reduced.<BR/><BR/>There are probably other organisms that thisJM O'Donnellhttps://www.blogger.com/profile/15032069850016819535noreply@blogger.comtag:blogger.com,1999:blog-11390444.post-1137024398469817462006-01-11T14:06:00.000-10:002006-01-11T14:06:00.000-10:00Interesting post, and a very interesting find on t...Interesting post, and a very interesting find on the ol' CCR5 receptor. I ran into it a few years back when doing some curiosity searches for a class paper on Pubmed, and the prevailing wisdom of the time (yes, only 4 years ago) suggested that the delta 25 mutation in the CCR5 receptor may have given resistence to a bacterial pathogen, yersinia pestis, the bubonic plague. Now, I think there's Karl Haro von Mogelhttps://www.blogger.com/profile/11409062416165090211noreply@blogger.com