Were these the last Neanderthals?

Small bands of them took refuge now and then in a massive cave near the southern tip of Spain. Now a study says charcoal from their fires indicates that Neanderthals were still alive at least 2,000 years later than scientists had firmly established before.

“Maybe these are the last ones,” said Clive Finlayson of The Gibraltar Museum, who reported the findings Wednesday with colleagues on the Web site of the journal Nature.

The paper says the charcoal samples from the cave, called Gorham’s Cave in Gibraltar, are about 28,000 years old and maybe just 24,000 years old.

Experts are divided on how strong a case the paper makes.

Neanderthals were stocky, muscular hunters in Europe and western Asia who appeared more than 200,000 years ago. They died out after anatomically modern humans arrived in Europe some 35,000 to 40,000 years ago and spread west into Neanderthal territory.

Scientists have long been fascinated by the last days of the Neanderthals. Were they doomed because they couldn’t compete with the encroaching modern humans for resources, or because they caught new germs from the moderns, or because of climate change? Did the two groups have much contact, and what kind?

They didn’t appear to encounter each other in Gorham’s Cave. More than 5,000 years separate the last traces of the Neanderthals from the earliest evidence of modern humans, Finlayson said. He believes the area near the cave contained small bands of Neanderthals and of advancing moderns at the same time, but over a large and varied landscape. So it’s not clear whether the two groups ever met, he said.

A reconstructed Neanderthal skeleton, right, and a modern human version of a skeleton are on display at the Museum of Natural History in New York. A new study says evidence in Gibraltar indicates that Neanderthals were still alive at least 2,000 years later than had been previously established.

Experts said the region is a likely place to find the last vestiges of Neanderthals, because it’s the tip of a geographic cul-de-sac that leads away from central Europe.

Eric Delson of Lehman College in the Bronx, N.Y., and the American Museum of Natural History, who did not participate in the research, said the paper’s 28,000-year-old date seems secure but its case for Neanderthals after that is shaky.

Even the older date is the only clear evidence of Neanderthals anywhere after 30,000 years ago, he said. But there have been prior claims of “the last Neanderthal” that were eventually shot down, and whether this one will hold up remains to be seen, he said.