I'm finishing up Crosby's Germs, Seeds, and Animals (Guns, Germs, and Steel was checked out, but I figure the original scholarly work is better, especially minus the race-denial in Jared Diamond's book). Over the summer I read Plagues and Peoples by McNeill, and I've still got a few of the later chapters left in Human Evolutionary Genetics. All emphasize the importance of infectious disease, especially when two previously kept-apart populations first encounter each other, since in the interim one of the populations may have undergone an arms race with microorganisms, such that they won't be utterly decimated when an outbreak occurs. Clearly any other population will be bulldozed over, as they've had no time to evolve defenses against the microbes. However obvious it seems in hindsight, this central dynamic of recent human history is left out of most high school material , so that only students interested enough to take in-depth courses in history in college might be exposed to it. I certainly heard nothing about it in high school, and I didn't take any history in college.
So I was trying to think of a popular example to get the gist across to other people who either didn't go to college or did but weren't exposed to the idea. Then it hit me -- Alien! Most of the scholarly work I've read so far on infectious disease and first encounters has focused on The Columbian Exchange that brought various Old World diseases to unprepared idigenous peoples of the Americas, wiping out somewhere around 90% of them. But the less stressed, though no less important, example was the lack of full-scale European colonization of sub-Saharan Africa, where the tables were turned on the Europeans who lacked defenses for the even nastier pathogens of the tropical areas, particularly the mosquito-borne ones like malaria. In Alien, much the same occurs to the crew of the Nostromo, a commercial ship sent to some remote area of space to haul back ore to enrich some corporation. They, however, are completely unprepared for the -- not ideological, geological, or technological differences, but the biological differences that meet them: namely, the parasitic Xenomorph. OK, so imagine someone blew up a Plasmodium falciparum protozoan big enough to easily scare the audience. One by one, the crew are either infected or killed by the parasite or its adult form, save for Sigourney Weaver's character Ripley. OK, so she survives by outwitting it rather than by chance possessing a genetically coded defense, but still.
The point remains: they encountered a biological form that they'd had zero exposure to, nor anything similar, and were thus unprepared for the infection by its initial parasitic form, resulting in the deaths of five of the six human characters. Had humans evolved with it in an arms race, and assuming its presence were a strong selection pressure, we might have evolved a grating to protect our mouths from being penetrated by the facehugger's egg-laying tube (and so would have altered our diet to exclude large solid foodstuffs), or perhaps a gag reflex that would function even if we were in a coma (a state induced by the facehugger) in order to keep it from laying eggs in our chests once it attached itself. Or something less exotic, like a change in the biochemistry of our lungs to make for an inhospitable environment for its eggs. In any event, we would be prepared to deal with it, rather than suffer near extinction.
As implied by the name of the crew's ship -- Nostromo -- the plight of the crew should be seen in the context of Europeans exploring the obscure and dangerous realms of foreign lands, a familiar theme from the work of Joseph Conrad. But unlike the moral murkiness of the strange land and the existential shock and horror of the explorers, which are at the core of Konrad's narratives, in the real world it was the biological menace which the wanderers had most to worry about; and their inner struggle against self-destruction was more biological in character, as their unsuspecting immune systems fought a mostly futile battle against the infection.
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 The only event I remotely recall was a brief mention somewhere of The White Devil purposefully distributing -- or catapaulting, was it? -- a batch of small pox-ridden blankets among the unsuspicious Native Americans, who all but disappeared for want of natural defenses against this Old World disease, in what was the first act of biological warfare. I almost feel glad remembering this, as it means the basic idea of different genetic profiles arising from adaptation to different environments must have gotten through to some textbook writer -- but then I realize that it's only worth mentioning in order to slam Whitey. It's also a complete distortion, as most of the indigenous who perished from Old World diseases were not the target of a plot by malicious Europeans to unleash the plagues upon them (though I'm sure the Europeans might have considered this if they had known microbiology back then). The distortion impairs any future efforts to protect indigenous peoples from diseases they've had no contact with, as it implies that all that we need to keep another near-extinction from happening is to cleanse Whitey of his moral sickness of wanting to enslave or kill off non-whites (which we know all Whites harbor deep down) -- rather than the solution that would actually work, namely cleansing Whitey of his microbial sickness. Those who were most saintly of purpose would still wipe out an uncontacted tribe, such as the Andaman Islanders (see also here and here), if they carried within their body the common cold.
This naked attempt to turn history into a "stick it to Whitey" competition just goes to show that the race warriors don't give a flying fuck about scientific findings or theories unless they can be put to the task of vilifying The Man. Not that the European colonists were kind souls -- indeed, they thought it was a sign of their being chosen by God that they survived outbreaks while the natives dropped like flies. But being nasty sons-of-bitches isn't disgusting enough of a portrait to paint of them, even if it's the most accurate -- they must be as villainized as possible, short of taking an overtly religious tone by calling them The Devil (though some groups do go there). Invoking religion, though, for the White textbook writers would cause them queasiness over appearing too low-rent. As Steve Sailer has mentioned before, anti-racist platitudes from well-to-do Whites are merely barbs aimed at other well-to-do Whites to show moral superiority -- the devil if it means that we might cause another massive die-off of people like the Andamanians just because we thought ourselves ethically cleansed of malice against dark-skinned people. Their safety and welfare aren't the real issues, so who can be bothered to read 20 minutes worth of basic biology to prevent further harm to them?