TG
Race and Human Evolution: A Fatal Attraction, by Milford Wolpoff and
Rachel Caspari. Simon and Schuster, $25; 448 pp., illus.
By Ian Tattersall
Similarly, Wolpoff and Caspari see continuity in European
fossils, with Neanderthals as an intermediate link in the chain that led to
modern Europeans. They believe that because they had fairly bulky brow
ridges over the tops of their eye sockets and (very occasionally)
braincases that bulged at the back, some (actually few) of the earliest
modern Europeans were descended from the
Neanderthals. But such a gestalt assessment of anatomy is not adequate. In
all modern people, the brow ridges, if any, are formed differently from
those of Neanderthals, and any protruding at the rear of the skull bears
none of the anatomical hallmarks of the Neanderthals.
To their credit, Wolpoff and Caspar1 are careful to disavow any
implication that the various extant human races have existed as discrete
entities throughout the past two milhon years; rather, during this time
"humans have been a single widespread polytypic species [that is, a species
with distinctive regional variants], with multiple, constantly evolving,
interlinked populations, continually dividing and merging" (italics
theirs). They are thus emphatic that the continuities they see in some
physical features do not mean the longterm persistence of discrete,
recognizable human populations.
Still, that two such thoughtful, erudite, and influential scholars
could claim that the extraordinary diversity of anatomies seen among the
fossil hominids of the past two million years should be brushed under the
rug of a single specles is as much proof as one
could ever wish of the extreme insularity of the science of
paleoanthropology. Unlike other branches of paleontology, paleoanthropology
is descended from human, not comparative, anatomy--an inheritance that has
brought with it an exquisite sensitivity to variation among individuals
within species. To recognize such variation is a salutary thing, but
postwar paleoanthropologists have too often fallen prey to the notion that
individual variation is almost the only kind of variation that we see in
the human fossil record.
As a result, the literature of paleoanthropology is cluttered with
references to various "archaic" forms of Homo sapiens that other
paleontologists would assign to distinct species. Not that paleontologists
working with other fossil animal groups ignore individual variation, but
they are also concerned with the patterns of diversity that signal the
presence of discrete species. And if we use normal paleontological
criteria, we find that extinct humans present a routine example of such
diversity. Modern human beings are the only surviving twig on a great,
branching bush of evolutionary experimentation .
No surprise, then, that the theory of multiregional continuity
represents only a sectarian reading of the human fossil record. But attack
is the best form of defense, and along the way Wolpoff and Caspari
take liberal swipes at viewpoints other than their own.
A particular target is the "African Eve" hypothesis preached by many
molecular biologists, who trace an unbroken line of descent among all
living humans to a female, probably a Homo sapiens, who lived in Africa
about 100,000 to 200,000 years ago. (Despite the implications of the name,
this Eve was nothing more than one member of the population that gave rise
to us all.) This notion has been widely debated, and Wolpoff and Caspari
score some significant hits. Nonetheless, the ultimate repository of our
evolutionary history is our fossil record, and despite Wolpoff and
Caspari's assertions to the contrary, right now the fossil evidence
suggests a relatively recent origin for Homo sapiens (perhaps 120,000 to
150,000 years ago), most likely in Africa.
This new species spread rapidly and, as successful species normally
do, developed regional variants during the climatic vicissitudes of the
last ice age. More recently, in contrast, the predominant (and equally
normal) process has been one of fusion among those variants, which is why
no modern systematist would attempt the hopeless task of classifying them.
Here is where Wolpoff and Caspari join the mainstream of paleontological
thinking, for they recognize, as clearly as anyone, that intraspecific
variants are ephemera: diversifying, combining, and disappearing in an
endless, braided stream. Hence, possibly, the Fatal Attraction of their
book's subtitle, which echoes the human misery that a fixation on the
fictitious purity of race has brought in its wake.
Ian Tattersall is chairman of the Department of Anthropology at the
American Museum of Natural History.
______________________________________________________________
Terry M. Gray, Ph.D. Department of Chemistry and Biochemistry
Calvin College 3201 Burton SE Grand Rapids, MI 49546
Phone: (616) 957-7187 FAX: (616) 957-6501
mailto:grayt@calvin.edu http://www.calvin.edu/~grayt/