tag:blogger.com,1999:blog-14297067.post7524003967131973864..comments2023-07-18T03:08:21.050-07:00Comments on PanCrit.Org: Gregory Cochran and Henry Harpending: The 10,000 Year ExplosionChris Hibberthttp://www.blogger.com/profile/12235621011708498622noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-14297067.post-45666574394906170352009-10-17T11:09:45.127-07:002009-10-17T11:09:45.127-07:00Hmmm. This was my own loose summary of the contin...Hmmm. This was my own loose summary of the continuing evolutionary environment they describe. I can't find a place where they talk about lower population density as a wellspring of new or newly introduced diseases.<br /><br />But I think this is right, even though the accepted version is that denser populations are reservoirs of diseases, and locations where existing diseases recombine and mutate. But I think it's away from major cities where new diseases arise or cross over to human hosts. <br /><br />People aren't living in close proximity to their livestock in major cities, though it is poor farmers, not pastoralists who act this way. I think if you look at the examples of AIDS and swine flu, you'll see that they weren't introduced to humanity in the cities, though the cities are where they breed and spread the best.<br /><br />Cochran and Harpending do point out that pastoralists have lower resistance to disease because they aren't exposed to the virulent conditions you cite. This may contribute to their ability to host new cross-overs before they've evolved features explicitly adapted to attacking humans. They also point out that when the old world explorers visited the new world, new diseases traveled both directions (Syphilis is the primare example.) The pastoralists had so much lower resistance in general so the consequences were more devastating.Chris Hibberthttps://www.blogger.com/profile/12235621011708498622noreply@blogger.comtag:blogger.com,1999:blog-14297067.post-86008454534846577902009-10-17T07:09:48.753-07:002009-10-17T07:09:48.753-07:00It surprises me to see sparser populations mention...It surprises me to see sparser populations mentioned as the breeding ground for new diseases. I haven't studied epidemiology in any depth, but my understanding was that cities tend to be the big breeding grounds for new diseases, for several reasons: they have large populations crowded together, they engage in trade and have regular foreign visitors, they're often build in unhealthy river bottom environments, and they keep livestock whose diseases organisms can mutate and afflict human populations (such as swine flu and bird flu). What factors do Cochran and Harpending think make low-density populations disease sources?William H. Stoddardnoreply@blogger.com