Israeli archaeologists said Monday they may have found the earliest evidence yet for the existence of modern man, and if so, it could upset theories of the origin of humans.

A Tel Aviv University team excavating a cave in central Israel said teeth found in the cave are about 400,000 years old and resemble those of other remains of modern man, known scientifically as Homo sapiens, found in Israel. The earliest Homo sapiens remains found until now are half as old.

"It's very exciting to come to this conclusion," said archaeologist Avi Gopher, whose team examined the teeth with X-rays and CT scans and dated them according to the layers of earth where they were found.

He stressed that further research is needed to solidify the claim. If it does, he says, "this changes the whole picture of evolution."