In many ways, the Neanderthal tumor is a needle-in-a-haystack find, Frayer said.
"People of that time didn't live as long as they did today; plus, there weren't very many of them compared to the Egyptians and people today," he told LiveScience. "So finding evidence of tumors and evidence of cancers, is -- I don't know if I want to say ‘lucky' -- but there isn't a lot of evidence for it."
Anthropologists and archaeologists are always debating how similar Neanderthals were to Homo sapiens who lived in their era, sometimes alongside one another, Monge said. The new rib analysis reveals that, in at least one area, modern humans and Neanderthals had a lot in common.
"They lived their lives basically the same way we did and basically with the same problems that we have," Monge said.
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