September 23, 2008

Neanderthals Enjoyed Broad Variety Of Foods

Experts now believe Neanderthals may have enjoyed a wide range of foods and a much broader menu than had previously been supposed.

Cave excavations in Gibraltar showed that they were once occupied by the ancient humans show they ate seal and dolphin when they could get hold of the animals.

Evidence even indicates that mussels were warmed to open their shells.

The findings contrast the popular view that Neanderthals ate a diet utterly dominated by meat from land animals.

Such findings provide more examples of the greater sophistication now being ascribed to Homo neanderthalensis as well as further complicating the story of how modern humans (Homo sapiens) out-competed and out-lived their evolutionary cousins.

Lead author Chris Stringer from London's Natural History Museum, said moderns still had a more efficient way of extracting the maximum out of the environment compared with the Neanderthals.

"So there still is an element of superiority, but it is a much more finely balanced one now. This is yet another difference that had been proposed between Neanderthals and moderns which now disappears," he said.

Professor Stringer and colleagues have been investigating the fossil material from a number of seaside excavation sites in Vanguard and Gorham's Caves in eastern Gibraltar.

Researchers say the cave deposits are throwing up a rich array of Neanderthal artifacts, demonstrating that Homo sapiens were not the only ones to live off the sea.

Earlier excavations showed that Neanderthals would eat some shellfish when available, but the Gibraltar study is the first to show the exploitation of marine mammals.

"We've got a shoulder blade of a seal with cut marks on it and we've got parts of the bones from a flipper with cut marks," explained Professor Stringer.

"These Neanderthals were skinning and dismembering seals. What's interesting is that they didn't always cook them; they often ate them raw, it seems.

"They were also heating bones, not to cook the meat but to get at the marrow inside. By putting bones in fires, they were making them more brittle so they could get them open more easily."

Evidence suggests they also ate dolphin (Tursiops truncatus), probably dead animals that had washed up on the beach. Monk seals (Monachus monachus), on the other hand, were most likely juveniles clubbed to death at breeding grounds and then taken back to the caves to be butchered.

By analyzing the different types, or isotopes, of atoms incorporated into Neanderthal bones as a result of the foods they ate, it is possible to glimpse something of their lifestyle.

It is clear that big game meat - mammoth, deer, horse - dominated the Neanderthal menu particularly in northern Europe.

By comparison, early modern human isotopes show a much broader range of foods as they were eating small grain, fowling and fishing.

This helps explain Neanderthal extinction: H. neanderthalensis may have struggled at times to get the most out of their environment and could be out-competed by moderns.

Professor Stringer believes the latest research, by demonstrating the exploitation of seal and dolphin, shows the extinction story is a little more complicated - at least as far as Gibraltar is concerned.

"We can't generalize to all Neanderthal populations, because the further north you go, away from the coast, you won't have those resources," he said.

The Gibraltar caves also contain hearths and flint stone tools, as well as butchered land mammals such as ibex (Capra ibex), red deer (Cervus elaphus), wild boar (Sus scrofa), bear (Ursus arctos) and rabbit (Oryctolagus cuniculus).

Mussel remains (Mytilus galloprovincialis) are also evident. These are found in ash and are scorched - clear evidence that they were cooked near a fire to open them.

Experts think the caves in Gibraltar may be among the very last places Neanderthals lived before they became extinct.

Analysis of charcoal remains from the hearths indicates the species was present 28,000 years ago, and perhaps as recently as 24,000 years ago.

London's NHM, Gibraltar Museum, and the Museo Nacional de Ciencias Naturales, Madrid are all collaborating on the excavation of the caves.

Professor Stringer and colleagues' findings are reported in the journal PNAS.


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