Paleontology: The Age of Man

In British India a generation ago, scientists unearthed two small fossils that consisted of no more than partial jawbones and a few teeth. For many years, they gathered dust—one in London's British Museum, the other in the Calcutta Museum. The ancient bones were largely ignored by professionals and the public alike. That oversight may have been one of paleontology's biggest bloopers. After carefully studying those neglected fossils, two Yale investigators have now become convinced that they are rare remnants of the first manlike creatures on earth.

The bones belonged to an extinct primate that paleontologists call Ramapithecus (the Latin word for ape, with a bow to the Indian god Rama). Scientists already knew that the creature lived in Asia and Africa 8,000,000 to 15 million years ago. But they have never known exactly where to place him on the evolutionary ladder. Did he belong to the family of apes? Or was he already a member of the family of man? The questions puzzled Yale Paleontologist Elwyn L. Simons, and his former student, David R. Pilbeam, both of whom had strongly suspected for some time that Rama was really more man than ape.

To test their theories, they engaged in some shrewd scientific detective work. Not only did they go through the usual painstaking steps of precise measurement, but they also ingeniously used the tiny fragments to reconstruct the creature's habits and habitats. Teeth, in particular, lend themselves to such paleontological probing.

Almost immediately, Simons and Pilbeam noted that the jawbones lacked the large overlapping canine teeth that are characteristic of all apes. Thus, Rama could grind his food with manlike side-to-side movements. Apes, on the other hand, mostly chomp up and down on their food, since their canines prevent lateral motion of the jaws. The Yale investigators also decided that Rama's molars had emerged one after another, as in man, rather than almost simultaneously, as in apes. From this evidence they drew two important conclusions: 1) Rama probably ventured into open country to forage for tougher foods than were available to apes ("the lotus eaters of the primates"), who stayed behind in the forests; and 2) he matured more slowly than apes, and more as human youngsters do, thus gaining valuable additional time to learn more skills during childhood.

In making their persuasive case for Ramapithecus as the first hominid, Simons and Pilbeam dispute a competing claim by the Kenyan anthropologist, Louis Leakey. Two years ago Leakey announced that 20 million-year-old fossils that he had discovered near Africa's Lake Victoria and dubbed Kenyapithecus africanus belonged to the earliest known manlike creature (TIME, Feb. 3, 1967). After applying their dental tests' to casts of Leakey's prehistoric fragments, the Yalemen decided that Kenyapithecus lacked the characteristics of early man. Though Leakey still insists that Kenyapithecus is a hominid, most other scientists now believe that he is an ape.