Fossil Find in Burma Suggests Asian Origin for Missing Link

As baseball season heats up, so does the race for the World's Oldest Fossil record. It's been a busy season so far. Discovery Channel, the Don King of the WOF, claimed the undisputed title for African contender Ida in a glitzy TV debut. Now, barely two months later. Ida's back in the ring, this time facing off against an Asian contender coming out of nowhere. Well, not exactly, Tales of its existence had been buzzed for about a decade Researchers have looked long and hard for the earliest anthropoids, advanced primates that were the ancestors of humans, apes, and monkeys. Until recently, most scientists thought anthropoids arose in Africa, where the oldest widely accepted members of the group lived as early as 37 million years ago in the Fayum province of Egypt. But recent evidence has pointed to an Asian origin. Fossils from that continent suggest that the first anthropoids could have been either Eosimias, a genus of tiny primates that lived 4 million to 45 million years ago, or a younger group called amphipithecids.The unveiling of Ida seemed to clinch the thing for the Afrocentrics but this newest find seems to flip the focus back to Asia. "It shows that Ida is out of the running as a [human] ancestor," says the fossil's discoverer, paleontologist K. Christopher Beard of the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania, as reported in Science magazine. In 2005, Beard discovered a 37-million-year-old jaw fragment in the badlands of central Myanmar. The jaw belonged to an amphipithecid, which Beard and paleontologist Jean-Jacques Jaeger of the University of Poitiers in France have named Ganlea megacanina in the Proceedings of the Royal Society B. Although the fossil is not nearly as sexy as a complete skeleton of Ida, Beard knew immediately that the jaw was something special to chew on. It has a huge canine tooth, which was used to pry open the hard shell of tough tropical fruits to eat the seeds, according to wear markings. This unusual feeding adaptation is found in the diminutive Saki monkeys of South America's Amazon Basin. This monkeylike behavior, as well as anatomical features in other fossils of amphipithecids from Asia, adds new evidence to the view that amphipithecids were early anthropoids and that anthropoids arose in Asia, says Beard. Others agree: These fossils "affirm the importance of Asia as a hotbed of early anthropoid evolution," says paleontologist Callum Ross of the University of Chicago in Illinois. Not everybody agrees this jaw can take a punch.Paleoanthropologist Russell Ciochon of the University of Iowa in Iowa City is onside with the Asian origin theory, he would like to see more evidence than just a fragmentary jaw. The new fossil, he says, does "nothing to provide resolution to the anthropoid origins debate." Ross counters that the new fossil is indeed important. It "provides important independent confirmation that Asian amphipithecids are closely related to [the most primitive] anthropoids," he says. Stay tuned for the next round, likely a Pay Per View thing on Discovery Channel.