Dying young was not likely the reason Neanderthals went extinct, said a study out Monday that suggests early modern humans had about the same life expectancy as their hairier, ancient cousins.

Scientists have puzzled over why the Neanderthals disappeared just as modern humans were making huge gains and moving into new parts of Africa and Europe, and some have speculated that a difference in longevity may have been to blame.

If anything, higher fertility rates and lower infant mortality gave modern humans an advantage over the Neanderthals, who died off about 30,000 years ago, said the study in the Proceedings of the National Academy of Sciences....