June 15, 2009

Researchers Find Partial Neanderthal Fossil In North Sea

Scientists in the Netherlands have found part of a Neanderthal man's skull that has been dredged up from the North Sea, BBC News reported.

The specimen is a fragment from the front of a skull belonging to a young adult male and experts say it is the first confirmed find of its kind.

The 60,000-year-old fossil has undergone an extensive analysis of chemical "isotopes" that match results from other Neanderthal specimens, suggesting a carnivorous diet.

This is the first confirmed specimen of ancient humans to have been recovered from the seabed anywhere in the world.

For most of the last half million years, sea levels were substantially lower than they are today. Large portions of the North Sea, at times, were even dry land "” making them rich habitats for large herds of ice age mammals.

Fishing trawlers and other dredging operations bring ashore large numbers of fossilized remains each year.

Some fishermen now even concentrate on collecting fossils rather than their traditional catch, according to Professor Chris Stringer, from London's Natural History Museum.

Stringer, a museum research leader, told BBC News there were mammoth fossils collected off the Norfolk and Suffolk coasts 150 years ago.

"So we've known for some time there was material down there that was of this age, or even older," he said, adding that some of the fossil material from the North Sea dates to the Cromerian stage, between 866,000 and 478,000 years ago.

He hopes eventually technology will reach a level where researchers can one day go down and search the sea floor to obtain the dating, associated materials and other information they would get while excavating on dry land.

Neanderthals (Homo neanderthalensis) were physically powerful hunter-gatherers dominated a wide range spanning Britain and Iberia in the west, Israel in the south and Siberia in the east. They appear in the fossil record some 400,000 years ago and are close evolutionary cousins to modern day humans.

Homo sapiens, our own species, evolved in Africa, and replaced the Neanderthals after entering Europe about 40,000 years ago.

The current Neanderthal specimen was uncovered in 2001 among animal remains and stone artifacts dredged up off the coast of the Netherlands.

Luc Anthonis, a private fossil collector from Belgium, spotted the fragment in the sieving debris of a shell-dredging operation.

Professor Jean-Jacques Hublin from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, led the study of the specimen.

Hublin told BBC News that even with this rather limited fragment of skull, it is possible to securely identify it as Neanderthal.

He noted the thick bony ridge above the eyes known as a supraorbital torus, which is typical of the species.

He also pointed out that the specimen's shape best matches those of the frontal bones of late Pleistocene examples of this human species, particularly the specimens known as La Chapelle-aux-Saints and La Ferrassie 1. He said the fossil also bears a lesion caused by a benign tumor known as an epidermoid cyst"”a type very rare in humans today.

Analysis of the isotopes of the elements nitrogen and carbon in the fossilized bone shed light on the types of foods eaten by the young male, according to Dr. Mike Richards from the Max Planck Institute in Leipzig.

Richards said the results show he was an extreme carnivore, surviving on a diet consisting largely of meat.

Previous research suggests that in Gibraltar, on the southern coast of Iberia, some Neanderthals were exploiting marine resources, including dolphins, monk seals and mussels.

"Dutch scientists - geologists and archaeologists alike - are hoping this find will convince governmental agencies that the Netherlands needs to invest much more in that... archive of Pleistocene sediments off our coast - and off the coast of Britain," said Professor Wil Roebroeks from the University of Leiden.

The individual was living at the extreme edge of the Neanderthals' northern range, according to Hublin.

He added that while those hunting grounds would at times have provided plentiful sources of meat for a top carnivore, Neanderthals living in these areas would have been at the mercy of fluctuations in the numbers of big game animals.

Dr. Hublin explained that local extinctions of Neanderthal groups might have been spurred by periodic dips in populations of mammals such as reindeer.


Image Caption: The frontal fragment of the Zeeland Ridges Neanderthal and its mirrored image superimposed on a complete Neanderthal skull from South-western France (Image: Max Planck Institute for Evolutionary Anthropology).


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