Forbidden Archeology_ The Full Unabridged Edition - Michael A. Cremo [477]
11.6.2 Evolutionary Significance of the ER 1470 Skull
Louis Leakey was pleased with his son’s discovery. ER 1470 vindicated his long-held view that a line of human ancestors, separate from Australopithecus and Homo erectus, extended far into the past.
Richard Leakey also believed his find had revolutionary implications for human evolution. “Either we toss out this skull or we toss out our theories of early man,” he wrote in National Geographic ( R. Leakey 1973b, p. 819). “It simply fits no previous models of human beginnings.” The model most widely accepted involved three steps. Australopithecus africanus, with some specimens as much as 3 million years old (Groves 1989, p. 198 ), gave rise to early Homo (H. habilis and then H. erectus), which in turn gave rise to Homo sapiens. But Leakey (1973b, p. 819) believed that the ER 1470 skull, larger and more humanlike than that of Australopithecus africanus, “leaves in ruins the notion that all early fossils can be arranged in an orderly sequence of evolutionary change.”
J. B. Birdsell (1975) of UCLA agreed this was true, even if the ER 1470 skull proved to be 2 million rather than 2.9 million years old. “From the very nature of its characteristics cranium 1470 does not seem to fit the standard scheme of the three grades of human evolution,” he wrote in the second edition of his textbook Human Evolution ( Fix 1984, p. 60).
In a National Geographic article, Richard Leakey included a chart showing two separate lines of hominid development. On one line, at about 3 million years ago, Leakey placed the ER 1470 hominid. Next on this line came Homo habilis at roughly 2 million years ago. At 1 million years ago, Homo habilis gave way to Homo erectus, which was followed at the very top of the chart by Homo sapiens.
The second (completely separate) line in Richard Leakey’s chart showed Australopithecus starting at 3 million years ago and finishing at 1 million years ago. Leakey (1973b, p. 819) commented: “Probably a relative rather than a forebear of mankind, apelike Australopithecus existed for at least 2 million years before it reached an evolutionary dead end.” Leakey believed, however, that further research would turn up a common ancestor for Australopithecus and the Homo line at around 4 million years ago.
Richard Leakey differed from his father by keeping Homo erectus in the direct line of human ancestry, “Most people would now agree that ‘1470’ should be called Homo habilis and that it is a direct ancestor of Homo erectus,” he wrote ( R. Leakey 1984, p. 154).
But the transition from ER 1470 to Homo erectus troubled Birdsell (1975), who wrote: “Anatomically in some ways such an evolutionary stage would seem retrogressive, for in a real sense it postulates that more archaic forms of men evolved out of a surprisingly advanced form, ER-1470” (Fix 1984, p. 137). Birdsell’s statement is of interest because the progression from Homo habilis to Homo erectus is one of the cardinal doctrines of recent evolutionary thought. If this progression turns out to be improbable, that would present severe problems for the conventional account of human evolution. The progression is arguably improbable because it involves, for example, going from skull ER 1470, with moderate brow ridges, to Homo erectus, with massive barlike brow ridges, back to Homo sapiens, with small brow ridges.
Such difficulties did not, however, trouble Richard Leakey. Recently, he said he considers Homo habilis and Homo erectus to be nothing more than early stages of one species—Homo sapiens (Willis 1989, pp. 154–155).
Richard Leakey has made other interesting statements about human beginnings. For instance, he wrote in his book Origins: “If we are honest we have to admit we will never fully know what happened to our ancestors in their journey towards modern humanity: the evidence is simply too sparse” (R.