c. Examine the debates related to Ramapithecus. (2013, Paper II Section A)
The current view of the Ramapithecus depends upon little more than two dozen fragments, mainly of teeth and parts of jaws that have been discovered since the first find reported on by G. Edward Lewis in 1934. The initial discovery prompted Lewis to
recognize a new form that he called Ramapithecus. This was followed in later years by a handful of fossils that were each recognized as new forms and they were given a series of separate names (Kenyapithecus, Graecopithecus, Rudapithecus, Sivapithecus) based upon the geographical localities at which they were found. But in 1965 Simons and Pilbeam reviewed the entire series and held the view that all these forms really comprised two species groups. One of these, Sivapithecus, was basically ape-like and it was therefore put forward as an ape ancestor; the other, Rudapithecus, seemed to possess a number of hominid-like features were therefore entered as an early hominid ancestor. This view was still extant in 1977 but a series of more recent studies have
cast doubt upon it. Thus Andrews and Cronin (1982) and Lipson and Pilbeam (1982) have all suggested that the non-Chinese ramapithecus are really only a single species or species group, that the two forms (Sivapithecus and Ramapithecus) are really only the males and females of the sexually dimorphic species group.
One of the reasons for putting forward this new idea is an attempt to make these data conform to those suggested by the concept of the molecular clock. The molecular clock, assessing the time from a common ancestry of two species using the notion that molecular evolution has taken place in a linear manner, suggests that human and African apes had a common ancestor at five million years ago or even close to the present time. If these were true, it would be logically impossible for there to have existed prior ancestors of humans (ramapithecines date from 8 to 14 million years ago) that were more like humans than apes. The new views of the fossils have therefore concentrated on the ape-like features of Ramapithecines and of these, big sexual dimorphism is one of the most powerful, being found in every great ape known, but not markedly present in any species of the genus Homo so far identified. But the later evidence regarding Ramapithecus strongly suggests that two species are present therein Yunnan. One of these, the larger creature, (Sivapithecus), with larger dental sexual dimorphism, larger canine dimorphism, larger canine heights and areas, more herbivorous dentition, considerably smaller number of males than females has attributes that are matched by many of the apes. In contrast, the smaller creature, (Ramapithecus) possess smaller dental sexual dimorphism, smaller canine dimorphism, smaller canine heights and areas, more omnivorous dentition and equal numbers of males and females, and thus has attributed that would not deny it a place in a radiation of prehuman form.