Leakey astounded his colleagues again when, at a scientific meeting in 1967, he argued that a lump of lava found at the Lake Victoria fossil site had been used by Kenyapithecus wickeri as a tool. The announcement, made with Leakey’s usual flourish, fell flat. Not one scientist in the audience asked a question, probably, as paleoanthropologist Elwyn Simons later observed, because they considered the idea “outlandish.” Mary Leakey, too, was unconvinced. “I can’t believe he really thought it was a 14-million-year-old stone tool,” she told biographer Morell after Leakey’s death. The incident, Morell writes in her 1995 book Ancestral Passions, “added to a growing suspicion that [Leakey’s] scientific judgment was slipping.”
It’s in the nature of paleoanthropology to undergo constant revision, as was made clear this past summer, when a new contender in the quest for the earliest hominid was announced. A six- to seven-million-year-old skull, found in Chad by paleoanthropologists from France, is older and yet appears more modern in several key respects than specimens from more recent times. Those features, plus its discovery far from Kenya or Ethiopia (the other leading candidates for the place where human beings split from the common ancestor we share with apes) are prompting experts to reconceptualize the human family lineage.
By the late 1960s, Leakey was little involved in fieldwork, partly because of ill health but also because he was devoting so much time to raising money for the many research endeavors he oversaw. He was, however, directing a dig at Calico Hills, east of Los Angeles. Hundreds of stone flakes had been recovered from the site, and the excavators believed them to be human artifacts. That was an extraordinary claim because the site was as much as 100,000 years old, and most anthropologists believe that humans came to the Americas no earlier than 30,000 years ago, and probably much more recently.
Leakey’s support of the Calico claim dismayed not only his friends and colleagues, but also Mary, and it would become a factor in their estrangement. In a poignant section of her autobiography, she characterized his position as “catastrophic to his professional career and . . . largely responsible for the parting of our ways.”
Yet despite his occasionally misplaced enthusiasms, Leakey remains a seminal figure. “Although Louis was not highly regarded for his science,”says PennState’s Alan Walker, “he made a major contribution in opening up East Africa for paleoanthropological exploration, making the science possible.” Others remember his pioneering spirit. “He had an energizing effect on the field and on the people doing the research,” says David Pilbeam, professorof anthropology at Harvard. “He could be sloppy and brilliant, prescient and foolish. But, given the time [in which] he was working, overall his instincts were right.”