Forbidden Archeology_ The Full Unabridged Edition - Michael A. Cremo [59]
A modern authority, Binford, stated (1981, p. 169): “There is little chance that an observer of modified bone would confuse cut marks inflicted during dismembering or filleting by man using tools with the action of animals.” Binford (1981, p. 169) further noted: “The marks of animals’ teeth are somewhat different. They follow the contours of the bone’s surface. . . . Tooth marks may frequently take the form of depressed or mashed lines. . . . On many of the wolf specimens, the tooth mark under magnification appears as a ‘cracked’ surface scar rather than as a cut or incision in the bone.”
But the teeth of sharks are sharper than those of terrestrial mammalian carnivores such as wolves and might produce marks on bone that more closely resemble those that might be made by cutting implements. After inspecting fossil whale bones in the paleontology collection of the San Diego Natural History Museum, we concluded that shark’s teeth can in fact make marks closely resembling those that might be made by implements. However, we also concluded that it is nevertheless possible, in some cases, to distinguish marks made by implements from those made by shark teeth.
Figure 2.3. Tooth of Carcharodon megalodon, a Pliocene great white shark (G. de Mortillet and A. de Mortillet 1881, plate 4, figure 19).
The bones we saw were from a small Pliocene species of baleen whale. The marks on one bone, a jaw fragment, were the subject of a report by Thomas A. Deméré and Richard A. Cerutti (1982 ) of the San Diego Natural History Museum. The ventral margin of the jaw fragment showed a pair of V-shaped grooves that ran transversely to that surface (Deméré and Cerutti 1982, p. 1480). One of the marks measured 16 mm (0.63 inch) long, and slightly curved. The other one ran 11 mm (0.43 inch) in a straight line. Our inspection of the incisions through a magnifying lens showed evenly spaced parallel longitudinal striations such as one would expect from the serrated edge of a shark’s tooth ( Figure 2.3). Even so, Deméré, who showed us the marked fossil at the San Diego Natural History Museum paleontology collection on May 31, 1990, stated that as far as he was concerned these V-shaped incisions alone were inconclusive. That is to say, they might have been caused by something other than shark teeth.
More useful for diagnostic purposes was another mark on the bone. Deméré and Cerutti (1982, p. 1480) described this as a beveled surface “characterized by 12 sinuous but parallel small-scale ridges and grooves.” Deméré and Cerutti (1982, p. 1480) went on to state: “This very distinctive pattern has been duplicated by us using a piece of paraffin and a tooth from the Pliocene great white shark, Carcharodon sulcidens Agassiz, 1843. . . . The teeth of Carcharodon are characterized by serrated
Figure 2.4. Pattern of grooves and ridges produced by a serrated shark tooth moving across the surface of a whale bone (Deméré and Cerutti 1982, p. 1481).
margins.” The pattern of grooves and ridges observed on the fossil whale bone (Figure 2.4) could have been produced by a glancing blow, with the edge of the tooth scraping along the surface of the bone rather than cutting into it. With this knowledge, it should be possible to reexamine the Pliocene whale bones of Italy and arrive at some fairly definite conclusions as to whether or not the marks on them were made by shark teeth. Patterns of parallel ridges and grooves on the surfaces of the fossils, such as those described by Deméré and Cerutti, would be an almost certain sign of shark predation or scavenging. And if close examination of deep Vshaped cuts also revealed evenly spaced, parallel longitudinal striations, that, too, would have to be taken as evidence that shark teeth made the cuts. One would not expect the surfaces of marks made by flint blades to display evenly spaced striations.