puzzle of the negrito: isolated archaic populations

Gerold Firl (geroldf@sdd.hp.com)
4 Dec 1996 21:34:21 GMT

Remnant populations of small, frizzy-haired, forest-dwelling peoples
still exist (or did within the last century) in isolated pockets
throughout asia, from the phillipines, malaysia, indonesia, the
andaman islands, and possibly india as well. Average height for men
ranged from around 4 1/2 feet to just under 5, leading to the name
"negrito", and begging the question of relations to the african
pygmies. How did the negritos come to be? The answer to this question
could have important implications for the history of human evolution.

The african pygmies are the best example we have of human adaptation
for a specialized environment. The equatorial african rainforest,
existing throughout multiple cycles of glacial advance and retreat,
presents special problems of survival and adaptation. All the
rainforest species are smaller than their savanna ancestors; one
antelope is the size of a rabbit. The human inhabitants of the forest
have adapted in similar directions; pygmy scale is well suited to the
heat, humidity, and dense growth.

The origin of the pygmies seems fairly obvious: they have evolved to
live in the forest, which has remained a stable environment
throughout the climatic fluctuations of the last few million years. It
isn't known how long the forest has been their home; the rainforest
has not yielded any fossil clues as of yet, and conditions are not
good for bone preservation. But what of the negritos? How did they
settle their far-flung range?

One possibility is that the negrito evolved, in-situ, just as did
their african counterparts. If we knew how long it took for the
african pygmy adaptation to evolve, that would provide a useful
comparison for the candleabra hypothesis.

Another possibility is that the negrito are the direct descendants of
african pygmies. The out-of-africa scenario would seem to require a
climatic epoch where tropical forests covered the intervening arid
territory between equatorial africa and india; have such conditions
ever existed?

A number of factors lend support to the out-of-africa hypothesis, none
of them conclusive; first of all, the negrito *look* african. Their
skin color is light by african standards (though pygmy skin color is
also lighter than their bantu neighbors), but the rest of their
physiology appears african. An interesting detail is the fact that the
negrito *sit* like pygmies, with their legs stretched out straight in
front of them; I know of no other people who sit that way. The socio-
economic relationship between the negrito and their neighbors is
strikingly analogous to that found in africa: the negrito trade meat,
honey, and other forest products for agricultural and manufactured
products from the villages. In common with the pygmies, the negrito do
not build a fixed abode, and they also have largely abandoned their
native language to adopt the speech of their neighbors.

The relic populations of vedda peoples found in indonesia, sri lanka,
and arabia felix provide another analogy; it seems unlikely that both
races co-evolved in-situ. One, if not both, must have arrived as part
of a great migration.

Keep in mind that asia has been occupied by hominids for at least a
million years, and throughout that time the 100,000 year glacial cycle
has repeatedly exposed and inundated the continental shelves, shifting
ecological zones southwards as the glaciers expanded, and then back
north during the interglacials. If, during one of the interglacials,
rainforest managed to extend around the horn of africa, up into
arabia, and around the persian gulf through the indus valley, then the
puzzle of the negrito may be solved.

Disclaimer claims dat de claims claimed in dis are de claims of meself,
me, and me alone, so sue us god. I won't tell Bill & Dave if you won't.
=-=-=-=-=-=-=-=-=-=-=-=-=-=---- Gerold Firl @ ..hplabs!hp-sdd!geroldf