Jan. 25 (UPI) -- Scientists believe an ancient human jawbone found in Israel belonged to a Homo sapien. The fossil, dated between 177,000 and 194,000 years old, suggests humans left Africa 50,000 years earlier than previously thought.
Last year, scientists found a 300,000-year-old Homo sapien fossil in Morocco. Previously, scientists thought Homo sapiens first emerged 200,000 years ago in East Africa.
Until recently, scientists thought modern humans left Africa in a mass exodus around 60,000 years ago, spreading out across Eurasia. Over the last decade, scientists have uncovered evidence that suggests the mass exodus was preceded by earlier, smaller migrations out of Africa, some as far back as 120,000 years ago.
The latest discovery -- detailed this week in the journal Science Advances -- pushes the earliest migration back even further.
The jawbone was first discovered in 2002 in Misliya Cave, the highest cave on Mount Carmel in northern Israel. Only recently were scientists able to accurately date the human bones.
Despite what the evidence suggested, scientists say it took a while for them to convince themselves of their own discovery. The jawbone is nearly twice as old as the next oldest Homo sapien fossil found outside of Africa.
"It looked so modern that it took us five years to convince people, because they couldn't believe their eyes," Mina Weinstein-Evron, an archaeologist at the University of Haifa, told The New York Times.
Through the years, a variety of artifacts suggesting the presence of early humans have been discovered among Carmel's cave complexes. The evidence suggests the story of human evolution began earlier and is more complex that previously thought.
"What Misliya tells us is that modern humans left Africa not 100,000 years ago, but 200,000 years ago," Israel Hershkovitz, lead excavator and a researcher at Tel Aviv University, told The Guardian. "This is a revolution in the way we understand the evolution of our own species."
Flint and stone fragments found in the caves suggest the early humans who inhabited them were accomplished hunters. But it's likely the population of Homo sapiens that made their way to the Arabian Peninsula nearly 200,000 years ago ultimately died out.
Genetic studies have confirmed that humans left Africa in waves, but the most modern DNA was supplied by the exodus of humans that left Africa 60,000 years ago. Still, the latest discovery offers further evidence that different groups of humans were on the move and interacting with one another much earlier than previously thought.