BOOK REVIEW : Fossil Hunters Face Off Against Geneticists in Human Studies : THE SEARCH FOR EVE<i> by Michael H. Brown</i> Harper and Row $22.95, 357 pages
Until half a century ago, biologists studied whole animals. Nowadays, the action in biology is in microbiology--the study of the chemistry of life. Hardly anyone studies whole animals any more.
The success of the molecular biologists has not been lost on researchers in related fields. If biochemistry is all there is to life--if it is all in the genes--why not use chemistry rather than fossils to study the history of the human species?
This idea, which got going three years ago, turns out to be much more controversial than it sounds. The fossil crowd is not giving up without a fight, and a lively debate has developed among paleoanthropologists between those who want to study genes and those who want to study bones.
Lively debate is something of a euphemism. In fact, there is a battle under way, and the battle is vividly presented in “The Search for Eve” by Michael H. Brown, a science writer with a knack for telling a good story.
“Enter the geneticists and the dramatic claims of the late 1980s,” Brown writes. “Into the fray of paleoanthropology, onto that emotional and venomous intellectual stage, against the backdrop of ape-men, came the lab coats and centrifuges and nucleotides. Of all intrusions into the clubby and rancorous world of Indiana Jones: geneticists! They were now going to discover what the fossil hunters couldn’t, what even the Leakeys could not find: the very first point of true modern origin, and they would also specify the time.”
The very idea of paleoanthropology is audacious: discovering the story of human origins, where we came from and how we got here. The evidence is sketchy and open to many interpretations. Sweeping conclusions are drawn from fragments of fossils.
As any researcher in the field will tell you, the bones tell conflicting stories, and many gaps have to be filled in with guesswork. Conventional researchers--the “fossil hunters”--have been arguing and feuding for years about the right interpretation of their discoveries. Which bones are significant and which were left by evolutionary dead ends?
“Each major anthropologist has a highly opinionated way of interpreting fossils and a highly individualistic way of presenting evolutionary trees,” Brown says.
The geneticists brought a new research tool to the party, and set off an uproar in the bargain. In a paper published on Jan. 1, 1987, in Nature, the eminent British science journal, Rebecca L. Cann, Mark Stoneking and Allan C. Wilson proposed ignoring the fossils altogether and instead analyzing DNA from the energy-producing compartments of the human cell known as the mitochondria.
This mitochondrial DNA is simple, well-known and easily traceable through the generations. Using this technique, Brown says, “They could look for the genes of cavemen in a future yuppie.”
And they did so, concluding that all human beings alive today could be traced to a single woman--Eve--who lived in Africa approximately 200,000 years ago. In one stroke, Cann, Stoneking and Wilson, who worked at UC Berkeley and the University of Hawaii, claimed to have solved the riddle of the origin of humanity.
But the old-school researchers, long accustomed to battling with each other, were not going to give up without a fight. “There is nothing more controversial to a paleoanthropologist than a claim that someone can precisely describe when and where and how man arose from a primordial, ape-filled past,” Brown writes.
The details of that still-raging battle fill a large chunk of this well-wrought book, but the analysis is hard to boil down to a paragraph or two. Suffice to say that, as in all debates, each side offers evidence that the other side pooh-poohs, and it is extremely difficult for an outsider to evaluate the conflicting claims.
Brown’s book has much to be said for it, starting with an intriguing subject. It also shows how science progresses by applying ideas from one field to another.
Finally, it’s a wonderful study of the sociology of science. The search for truth may motivate scientists, but more important is the search for glory.
Next: “Lifelines From Our Past: A New World History” by L.S. Stavrianos (Pantheon).
