Ancient peoples had heavier brow ridges than modern Europeans. "The faces were also broader and the jaws were heavier," Brace added.
Skeletal remains from Greece and elsewhere are thought to represent Neolithic settlers who introduced farming from modern-day Syria, Jordan, and Israel. Brace said these remains have facial measurements that don't match those of most present-day Europeans.
The anthropologist added that despite some similarities with modern Mediterranean populations, "the farther north and west you get, the less they resemble the people living there now."
"Modern Europeans don't look like the incoming Neolithic [farmers]," he said. "It's pretty clear that there's a much larger component of the indigenous foraging peoples across Europe, and they existed in far greater numbers than the archaeological record had led us to believe."
The study suggests that Neolithic remains, which have been taken as evidence of large-scale colonization, are misleading.
Brace says pots associated with Neolithic farmers tended to disintegrate into countless shards, creating the impression of a larger presence than was actually the case.
Early farmers also buried their dead together, unlike the native inhabitants, leaving groups of bodies for archaeologists to later uncover along with other artifacts.
The researchers say the fact that incoming settlers didn't pass on telltale facial characteristics to later Europeans suggests that they were absorbed by the indigenous hunter-gatherers.
"They absorbed them geneticallyand their way of life," Brace said. "Molecular biology is telling us the same story."
Recent DNA analysis of the skeletons of prehistoric farmers found buried in Germany, Austria, and Hungary appears to show that they contributed little to the European gene pool. (See related story.)
A quarter of those analyzed remains share a DNA signature that is now extremely rare worldwide and which has left virtually no trace on living Europeans.
Those findings, described last month in the journal Science, suggest that "the contribution of early farmers could be close to zero," according to Peter Forster, archaeology research fellow at Cambridge University, England.
Other experts now broadly agree that the spread of farming across Europe represents more of a cultural legacy than a genetic one.
"Personally, I think it's a question that can be answered only on a regional basis," said Marek Zvelebil, professor of archaeology at the University of Sheffield, England.
"In some areas, particularly parts of the East Mediterranean and central Europe, you do have small groups of people migrating from the Near East," he said.
"But in most other parts of Europe, particularly western and northern Europe, you have local hunter-gathering people adopting farming."
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