Reading the Nov ‘09 issue of Scientific American in post-Thanksgiving tryptophane torpor yields these developments in Spatial Medicine:
http://www.scientificamerican.com/article.cfm?id=rethinking-the-hobbits-in-indonesia
Remember the Homo floriensis find? A small island of Flores in the Indonesian archipelago yielded up fossils of a very small (and small-brained) human who lived there a mere 17,000 years ago (by reliable dating) but who bears a remarkable similarity to Lucy, the famous australopithecus afaensis.
Now, there are really only two explanations for this finding, which under current human derivation theories is about as likely as ‘bird shit in a cuckoo clock’, to quote a famous scientist:
1) There were far earlier immigrations out of our common ancestry in Africa before homo erectus made his pretty-well confirmed diaspora through the Middle East, moving down the coat to India and Asia, with a group doubling back to Europe. The supposition that 1 meter-tall proto humans with brains 1/3 the size of ours managed to emigrate from Africa to Indonesia (the work of many generations), develop tools, and live with us up until the most recent Ice Age is a lot to swallow and sets the now-common theories of hominid development right on its head. Others prefer to say:
2) These hobbits were homo erectus who were simply isolated long enough to go miniature (which has been documented in other mammals, but never in man - the Pygmies are just a very early breakaway group). But the insular dwarfism theory doesn’t stand up to an analysis of the bones and bony relationships, so the second theory is that these fossils are showing the effects of a disease on a group of ‘us’ modern humans.
This second theory is a kind of cop-out - what disease would produce characteristics of an earlier form of human like homo habilis? (Several are offered actually, my favorite being ‘microcephalic osteodysplastic primordial dwarfism’ - a genetic disorder that would produce small bodies and small brains but normal intelligence.) But in order to defeat this disease hypothesis, we need to find other hobbit skeletons and particularly a skull that would show that these humans were widespread and normal, not this specific, possibly diseased, specimen, LB1 as it is known.
If the first theory is right, then it shows how little we know about our family tree between apes and us, and the question of what makes humans unique and what accounts for our strange characteristics is as yet unanswered. I of course prefer this route, as a proponent of the aquatic ape theory (or at least giving Elaine Morgan a good listen), I would love to have the apple cart upset to see a more checkered past, not the linear progression current science prefers.The idea that other kinds of humans co-existed with us until very recently, like the Neanderthals, is very appealing.
On the other hand, if the second theory proves true, it only goes to show on what slender evidence - the one or two fossils available - we hang these complex theories of evolution. I am sure we will be finding detection methods in the next decade that will allow many more hominid fossils to be found, and then the picture might be clearer and more reliable. Until then, I love the available fantasies of multiple kinds of humans roaming the earth together - now there’s grist for a story mill!