A short history of nearly everything - Bill Bryson [220]
In the following years as more bones were found and identified there came a flood of new names—Homo aurignacensis, Australopithecus transvaalensis, Paranthropus crassidens, Zinjanthropus boisei, and scores of others, nearly all involving a new genus type as well as a new species. By the 1950s, the number of named hominid types had risen to comfortably over a hundred. To add to the confusion, individual forms often went by a succession of different names as paleoanthropologists refined, reworked, and squabbled over classifications. Solo People were known variously as Homo soloensis, Homo primigenius asiaticus, Homo neanderthalensis soloensis, Homo sapiens soloensis, Homo erectus erectus, and, finally, plain Homo erectus.
In an attempt to introduce some order, in 1960 F. Clark Howell of the University of Chicago, following the suggestions of Ernst Mayr and others the previous decade, proposed cutting the number of genera to just two—Australopithecus and Homo—and rationalizing many of the species. The Java and Peking men both became Homo erectus. For a time order prevailed in the world of the hominids.*47 It didn't last.
After about a decade of comparative calm, paleoanthropology embarked on another period of swift and prolific discovery, which hasn't abated yet. The 1960s produced Homo habilis, thought by some to be the missing link between apes and humans, but thought by others not to be a separate species at all. Then came (among many others) Homo ergaster, Homo louisleakeyi, Homo rudolfensis, Homo microcranus, and Homo antecessor, as well as a raft of australopithecines: A. afarensis, A. praegens, A. ramidus, A. walkeri, A. anamensis, and still others. Altogether, some twenty types of hominid are recognized in the literature today. Unfortunately, almost no two experts recognize the same twenty.
Some continue to observe the two hominid genera suggested by Howell in 1960, but others place some of the australopithecines in a separate genus called Paranthropus, and still others add an earlier group called Ardipithecus. Some put praegens into Australopithecus and some into a new classification, Homo antiquus, but most don't recognize praegens as a separate species at all. There is no central authority that rules on these things. The only way a name becomes accepted is by consensus, and there is often very little of that.
A big part of the problem, paradoxically, is a shortage of evidence. Since the dawn of time, several billion human (or humanlike) beings have lived, each contributing a little genetic variability to the total human stock. Out of this vast number, the whole of our understanding of human prehistory is based on the remains, often exceedingly fragmentary, of perhaps five thousand individuals. “You could fit it all into the back of a pickup truck if you didn't mind how much you jumbled everything up,” Ian Tattersall, the bearded and friendly curator of anthropology at the American Museum of Natural History in New York, replied when I asked him the size of the total world archive of hominid and early human bones.
The shortage wouldn't be so bad if the bones were distributed evenly through time and space, but of course they are not. They appear randomly, often in the most tantalizing fashion. Homo erectus walked the Earth for well over a million years and inhabited territory from the Atlantic edge of Europe to the Pacific side of China, yet if you brought back to life every Homo erectus individual whose existence we can vouch for, they wouldn't fill a school bus. Homo habilis consists of even less: just two partial skeletons and a number of isolated limb bones. Something as short-lived as our own civilization would almost certainly not be known from the fossil record at all.
“In Europe,” Tattersall offers by way of illustration, “you've got hominid skulls in Georgia dated to about 1.7 million years ago, but then you have a gap of almost a million years before the next remains turn up in Spain, right on the other side of the