Sunday, October 31, 2010

AiG News to Note, October 30, 2010

Answers in Genesis refers to the discovery of  what appears to be a hundred-thousand-year-old Homo sapiens jawbone in China as "win[ning] two points for creationist views."  First, it contradicts evolutionary theories, and second, since the jaw's morphology seems intermediate between modern human and Neanderthal jaws (and thus implies interbreeding between H. sapiens and H. neanderthalensis), it contradicts the idea that there were multiple species  alive at various times in the  history of our species.  I should point out in passing that, by creationist logic, this is resting a rather large case on a rather fragmentary finding.  More relevantly, I don't see it as that big a problem even for mainstream reconstructions of human prehistory, much less for evolutionary theory in general.

Anatomically modern humans are known from fossils nearly twice as old as the new Chinese specimen.  It is certainly plausible that the migration out of Africa from which modern Eurasian, Australian, and American humans are descended was not the first attempt to leave the African continent by anatomically modern humans.  On the other hand, as the AiG article notes, paleoanthropologist John Hawks has noted that the jawbone is within the known range of variation of both modern humans and Neanderthals: while he himself suspects that its bearer had anatomically modern human ancestors, it might be just another "archaic H. sapiens" that has no effect on current theories of when and how humans spread out from Africa.  As the article also notes, there is no consensus on whether modern humans and Neanderthals were separate species or merely separate -- and sometimes interbreeding -- subspecies, implying that some evolutionists won't find their ideas challenged at all if this jawbone is indeed from a modern human-Neanderthal hybrid (there is in fact strong evidence that Neanderthals and anatomically modern humans interbred, but this may not have been more regular or common than, say, the interbreeding that sometimes goes on between brown bears and polar bears and may not imply that modern and Neanderthal humans were the same species).

Oddly, AiG nowhere takes issue with or even makes snarky comments about the dating of the fossil.  Given their persistent and adamant young-earth creationism, I wonder if they don't want to stress the point that "evolutionists" don't just make up the dates to fit their theories, but find the dates indicated by the evidence.

The AiG article next comments on  a story on how New Caledonian crows learn tool use from their parents.  After a brief diversion to another story about bees able to find the shortest path among a variety of flowers (the famously difficult "travelling salesman problem"), the article argues that this discovery contradicts evolutionary theory again, by showing that apes don't support evolution just because they're smart.  Well, of course, apes don't support evolution just because they're smart; they support evolution by numerous genetic and anatomical homologies with humans, and because humans are nested, anatomically and genetically, among other primates.  One would think that an organization that has figured out that evolution predicts an evolutionary tree of life rather than an evolutionary ladder, and is aware of the idea of convergent evolution, would realize that evolutionary theory is not overturned by the discovery that primates are not the only tool-users on the planet.

The "News to Note" article has a brief paragraph on a recent suggestion that a drastic rise in oxygen levels in the Earth's atmosphere a couple of million centuries before the onset of the Paleozoic (and the "Cambrian Explosion") was caused by algae blooms triggered by retreating and advancing glaciers of a worldwide ice age that reached, at the time, nearly to the equator (the "snowball Earth").  It notes, of course, that creationists only accept one ice age, right after Noah's flood about 4500 years ago, notes that the geological record isn't very complete, and segues into the question of how life could evolve to breathe oxygen in the first place.  It's not quite clear whether the writer grasps that the scientists who proposed the idea think that animals -- all of whom breathe oxygen -- already existed on Earth in very primitive forms such as sponges.  And it seems rather odd to argue that, given experiments in which bacteria evolve the ability to metabolize weird substances such as nylon, that mutations and natural selections are unlikely to be able to give an organism the ability to use oxygen.

The article goes on to consider a report of a headless dragonfly and part of a small lizard fossilized in million-century-old amber.   This of course confirms creationism because lizards that eat dragonflies exist today, and the amber is probably only thousands rather than tens of millions of years old.   "We would," the author explains, "certainly expect to find significant similarities of behaviors and ecosystems between the time periods."  Of course, we would, if we were AiG-style creationists, also expect house cats and lions to diverge from a single pair of ur-felids aboard Noah's Ark in under 5000 years, and perhaps even expect the entire Equidae, from Hyracotherium to modern donkeys and zebras, to similarly "microevolve" from a single pair of ur-equids in the same time.  It's not really clear, given that sort of warp-speed evolution, and the "world that perished" view of a radical discontinuity between the pre- and post-flood worlds, why creationism is more supported than evolutionary theory by the idea that lizards and dragonflies existed together in the days of the dinosaurs as they do today.

Finally, the article responds to a column on complaining that creationists attack Darwin personally rather than deal with evolutionary theory as it is.  The article points out, reasonably enough, that in fact many of its articles don't even mention Darwin.  The author omits, though, quite a few AiG articles that deal with the supposed evil effects of people accepting Darwin's ideas rather than with either the scientific merits of the theory or the modern theory as opposed to Darwin's own formulations.

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