The almost complete fossil skull (and pieces of thirty individuals) of Kenyanthropus platyops was discovered in 1999 by Justus Erus, a member of Dr Meave Leakey’s team at Lomekwi in Kenya. The team had been searching in the 3.2 to 3.5 million year old sediments of Lomekwi River for Australopithecus afarensis fossils. Instead of finding contemporaries of Lucy, they came across the skull of a hominid that was so different from Australopithecines that it was given its own genus and species name: Kenyanthropus Platyops, meaning 'the flat-faced man of Kenya'.
The discovery was shocking in a number of ways. Most researches had previously believed that tall, flat faces did not develop until two million years ago. The flatness of Platyops’ face is due to less pronounced brow ridges and raised cheeks (both relatively modern traits). At the same time, Platyops had small ear canals like those of Ardipithecus ramidus and Australopithecus anamensis (both older, more primitive hominids).
The teeth of this species are good indicators that Platyops and Afarensis could have easily lived side by side without competing for food resources. Platyops’ small molars and lack of sagittal crest indicate that it ate soft foods like fruit and grubs, which do not need large grinding surfaces or powerful muscles to process. This less specialized dentition (lacking in very pronounced canines or large, flat molars) is comparable to that found in later, more modern hominids.
Platyops has been compared most closely to Homo Rudolfensis or Homo Habilis, species which lived about a million years later, and there is speculation of a direct ancestral line. Previously, A. afarensis was thought to have been the sole hominid of its time period, thus making it an easy “trunk” on the evolutionary tree, from which all later hominids branched. The discovery of Platyops marked an addition to the puzzle of human ancestry that will only become more clear if or when more fossil specimens are found.
There are those who do not support Kenyanthropus platyops as a new genus and species. Critics note the extensive warping of the skull that might have caused the flat-faced appearance and, if the flatness is not due to warping, that no evolutionary precendent can be identified. There have also been no post-cranial fossils found, and thus, bipedalism cannot be determined (the most important basis of assigning hominid status).
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