![Figure][1] Willandra Lakes region. CREDIT: LYNN SALMON Most scientists think modern humans evolved only in Africa. But the theory of “multiregionalism” still has its holdouts who think Homo sapiens evolved all over the Old World. Now the biggest study yet of fossil skulls from Australia, Indonesia, Africa, and the Middle East has delivered another blow to that theory. Paleoanthropologist Michael Westaway of the Queensland Museum in Brisbane, Australia, and primatologist Colin Groves of the Australian National University in Canberra compared 26 15,000- to 40,000-year-old skulls from the Willandra Lakes of New South Wales, Australia, with skulls of 19 early modern humans, dated at up to 195,000 years old, and five H. erectus skulls from Java (dates uncertain). Puzzlingly, the Willandra skulls include both light (gracile) and heavy-set (robust) crania. The out-of-Africa camp thinks they all descend from a single population, but some multiregionalists argue that they could have two sets of roots: in robust Indonesian H. erectus and gracile people from China. The researchers looked for signs that the robust Willandra individuals inherited some traits, such as a distinctive brow ridge, from the Indonesian hominins. They found none, they reported in the journal Archaeology in Oceania . “There were commonalities between the Australian, African, and Middle Eastern people, but the Indonesian specimens stood outside the range,” Westaway says. But paleoanthropologist Fred Smith of Illinois State University in Normal says the jury is still out. He thinks modern humans arose in Africa but later bred with archaic locals around the globe. “I'm still not convinced that it [the study] proves there is no assimilation,” he says. [1]: pending:yes