3. Form of the talus (ankle bone) is like that “seen in the extant African apes” ( p. 291).
4. Disposition of the heel similar to that of gorillas and chimpanzees ( p. 291).
5. Hallux (large toe) capable of being extended sideways, with some “residual grasping functions” ( p. 293).
Apelike Features of the oh 8 Foot Reported by o. j. lewis (1980)
Commenting on the 1964 study by Day and Napier, Lewis (1980, p. 294) noted that “conservative arboreal features of the tarsus [ankle] . . . escaped comment.” The suggestion that the OH 8 ankle manifested arboreal features is intriguing. It certainly does not serve the propaganda purposes of evolutionists to have the public visualizing a supposed human ancestor like Homo habilis
climbing trees with an aboreally adapted foot rather than walking tall and brave across the African savannahs. When the owner of the OH 8 foot did walk on the ground, it probably did so in a chimpanzeelike manner, said Lewis (1980, p. 296).
From Lewis’s study of the OH 8 foot, one could therefore conclude that Homo habilis
was much more apelike than most scientists have tended to believe. The OH 62 discovery supports this view. Another possible conclusion: the OH 8 foot did not belong to Homo habilis but to an australopithecine. This view was favored by Wood (1974b) and Lewis (1980, p. 295). A related conclusion is that Homo habilis itself was, as Oxnard (1975b) proposed, simply a variant of Australopithecus. Oxnard, said Lewis (1980, p. 295), thought “the australopithecines (including OH 8) were at least partially arboreal primates retaining efficient climbing capabilities associated with a bipedal capacity probably of a type no longer seen.” Of course, the proposal that Australopithecus was even partially arboreal defies the conventional view that this creature was humanlike from the neck down and walked fully upright on the ground. In Section 11.8, we give a detailed discussion of this issue.
Over the years, scientists have described the OH 8 foot skeleton as humanlike ( Day and Napier 1964), apelike ( Lewis 1980), intermediate between human and ape ( Day and Wood 1968), distinct from both human and ape (Oxnard 1972), and orangutanlike ( Lisowski et al.
1974). This demonstrates once more an important characteristic of paleoanthropological evidence — it is often subject to multiple, contradictory interpretations. Partisan considerations often determine which view prevails at any given point in time11.7.3.2 The OH 7 Hand
The OH 7 hand was also found at Olduvai Gorge (Section 11.4.2), as part of the type specimen of Homo habilis.
Napier (1962, p. 409) described the hand as quite human in some of its features, especially the finger tips. As in the case of the OH 8 foot, subsequent studies showed the OH 7 hand to be very apelike, calling into question either its attribution to Homo habilis or the generally accepted humanlike picture of Homo habilis, which the original interpretation of the OH 7 hand helped create.
C. E. Oxnard (1984, p. 334-ii) was highly critical of Napier’s original study of the Homo habilis
hand: “being convinced that he was looking at a pre-human hand that made tools, he interpreted three features in which that hand was similar to a human hand as more weighty than ten in which he found it similar to those of apes.” Oxnard identified evolutionary bias (seeing a fossil as “pre-human”) as the key factor in Napier’s attempt to characterize an essentially apelike structure as human.
Randall L. Susman and Jack T. Stern noted that the OH 7 finger bones had large areas for the insertion of a muscle (the flexor digitorum superficialis) that apes use when hanging from branches. “The impressions for this muscle are greater in relative area than in any living ape or modern humans,” they said (Susman and Stern 1979, p. 572).
Susman and Stern (1979, p. 565) therefore concluded: “Prominent markings for insertions of these muscles in a fossil hand (such as O.H. 7) suggest use of the forelimb in suspensory climbing behavior.”
Susman and Stern (1979, p. 572) noted in addition that the finger bones of the OH 7 hand were thick and curved like those of chimpanzees, indicating, like the flexor digitorum superficialis muscle, a degree of arboreal suspensory behavior.