pointed — and still points — to Africa, confirming 

 Darwin's insight. 



Although the overall case for African human ori- 

 gins is strong, disputes still rage around important de- 

 tails. For example, did the eastern Asian H. erectus or 

 European Neanderthal populations contribute in any 

 way to the gene pool of Homo sapiens, or were they 

 dead ends? The questions are not purely of academ- 

 ic interest, as they potentially play into nationalistic 

 and racial preconceptions. One would think the birth- 

 place of our much earlier primate ancestors would not 

 evoke such distractions. Still, the possible honor of 

 that distinction was one reason the Burmese govern- 

 ment was so supportive of paleontological prospect- 

 ing in the Pondaung Hills. And as objective as they 

 try to be, paleontologists are bound to hope that the 

 fossils they discover, wherever they originate, are the 

 centerpiece of some evolutionary story. In that con- 

 text, the Myanmar fossils and other candidates for an- 

 thropoid origins deserve careful evaluation. 



Pondaungia was described scientifically in 1927 on 

 the basis of one specimen, consisting of three jaw frag- 

 ments, and Ainpliipithccus was described in 1937, on 

 the basis ofjust one jaw fragment. In spite of the lim- 

 ited nature of the specimens, both bore some resem- 



Prosimians 



blance to anthropoid fossils that had been discovered 

 in the Fayum desert of Egypt. Because the Burmese 

 primates appeared to be older than the Egyptian ones, 

 it seemed plausible that anthropoids originated in Asia. 



Things started to change in 1978. More and better 

 fossils of both Pondaungia and Amphipithecus began to 

 emerge in Burma, thanks to the work of American 

 and Burmese teams and, later, French and Japanese 

 teams. At first the new specimens seemed to confirm 

 the anthropoid status of the Burmese primates (hence 

 the title of Ciochon's 1985 article, "Fossil Ancestors 

 of Burma"). But as more complete material began to 

 appear, that view was thrown into doubt. 



Today about forty numbered primate specimens 

 have been catalogued from the Pondaung Hills 

 of Myanmar (a specimen sometimes comprises sev- 

 eral separate fragments). All told they represent parts 

 of approximately twenty-five individual animals. 

 Among the new discoveries are upper and lower 

 jaws of a new genus, Myanmarpithecus, which, along 

 with Pondaungia and Ainpliipithccus, has been placed 

 in the family Amphipithecidae (the amphipithe- 

 cids). Siamopithecus, another member of the family, 

 was recently discovered in southern Thailand. In the 



Anthropoids 



Fused metopic 



Open bone 

 behind eye 



suture 



premolar 



More robust, 

 complex premolars 



Details of primate bones and teeth enable investigators to distinguish 

 anthropoids (above right) and the other main group of primates, the 

 prosimians (above). Other features, including DNA, are useful in determin- 

 ing the family relationships among the living species, but paleontologists 

 generally must rely on the "hard" evidence retained in fossil remains. 



NATURAL HISTORY March 2006 



