Neanderthals may have eaten the stomach contents of some of the animals they killed, scientists have found.
Two researchers at London's Natural History Museum said that eating chyme may explain the presence of some plant matter found in a Neanderthal's tartar-crusted teeth.
Last year, researchers studying calcified plaque on Neanderthal fossil teeth found in El Sidron cave in Spain concluded that Neanderthals cooked vegetables and consumed bitter-tasting medicinal plants such as chamomile and yarrow.
The findings suggested this extinct human species were not brainless carnivores.
The new research by Laura Buck and Chris Stringer, published in the Quaternary Science Reviews, has challenged the conclusions of the Spanish study.
"Dental research does not prove that Neanderthals were self-medicating, vegetable-eating sophisticates," one of the researchers told the Observer.
Stringer argued in the study that the tiny pieces of plant found in Neanderthal teeth may have become embedded in the stomach contents of deer, bison and other herbivores that had then been hunted and eaten by Neanderthals.
"Many hunter-gatherers, including the Inuit, Cree and Blackfeet, eat the stomach contents of animals such as deer because they are good source of vitamin C and trace elements," said Stringer.
"For example, among the Inuit, the stomach contents of an animal are considered a special delicacy with a consistency and a flavour that is not unlike cream cheese. At least that is what I am told," he said.
"The mistake is to think that because you find plant fragments in teeth that they must have got there because these carnivores - in this case Neanderthals - had consumed them as part of a carefully constructed diet or were taken because it was realised that certain herbs and grasses had health-promoting properties," added Buck.
"In fact, they may have got there purely because Neanderthals liked to eat the stomach contents of some of the animals they killed," Buck said.
The researchers stressed that they are not arguing that Neanderthals definitely did not eat vegetables or could not have used certain herbs as medicines.
"What we are saying is that the evidence of plant fragments in Neanderthal teeth is simply not strong enough to prove that they did so," they said.
