New data suggests that our evolutionary cousins, the Neanderthals, may have been diving under the ocean in search of clams.
It adds to the growing evidence that the old image of these ancient peoples as brutal and unimaginative is wrong.
Until now, there had been little clear evidence that Neanderthals were swimmers.
But a team of researchers who analyzed shells from a cave in Italy said some should have been collected from the seabed by Neanderthals.
The findings have been published in the journal Plos One.
The Neanderthals who lived in Grotta dei Moscerini, in the Lazio region, about 90,000 years ago, were transforming clam shells into sharp tools.
Paolo Villa, of the University of Colorado, Boulder, and his colleagues, analyzed 171 such tools, which come from a local species of mollusks called smooth clam (Callista chione) The tools were excavated by archaeologists in the late 1940s.
Clam shells that are washed on the beaches can be distinguished from those that are still alive when they meet.
Stranded specimens were opaque, sanded when struck against pebbles on the shore, drilled by other marine organisms and embedded with barnacles.
Most of the specimens in Grotta dei Moscerini meet the criteria of shells that were collected on a beach.
But a quarter of them had a bright and smooth exterior, which showed no signs of such wear. This suggested that they were collected from the seabed while the clams were alive.
Today, Callista chione Most of the time it is caught by dredging, using small boats or collected by divers in waters of the Adriatic coast that are more than 10 m deep.
In the northern part of the Adriatic, however, there are some sandbars where Calista Clams can be collected at depths between half a meter and one meter. In this case, clams can be caught simply by wading.
But, Paola Villa said: “It is very possible that Neanderthals were collecting projectiles of up to two or four meters,” he added, “of course, they had no diving equipment.”
Dr. Matt Pope of the UCL Institute of Archeology, who was not involved in the study, told BBC News: “We can all find exceptional situations in which, during a storm, clams are thrown on the beach.
“But it is the fact that they occur in more than one [archaeological] unity, is the fact that they occur as part of a system of material that goes beyond this cave, suggesting that something more than a strange event is happening. “
The evidence is in stark contrast to our ancient vision that Neanderthals spent much of their time chasing or cleaning big game animals.
It is known that Neanderthals collected mussels from estuaries and fished in shallow waters, but there has been little clear evidence of swimming, diving or, in some cases, perhaps wading.
“It is more evidence to place Neanderthals in these coastal environments and at certain times making use of coastal resources, not only as food, but also as raw material for tools,” said Dr. Pope.
He said that decades ago, this type of resource collection had been used to distinguish the first examples of our own species, Homo sapiens, of the Neanderthals. “We can no longer find that distinction,” he said.
“The good thing about this document is that it covers a site that, at certain times, when you have high sea levels … it is right on the coast. You can see that they do not live there in large quantities for long periods of time. It seems that they are making short trips and they come equipped, bringing materials they might need, such as pre-existing tools. “
“Maybe it’s a place where they camp seasonally, at certain times of the year. Maybe one of the things that attracts them is these seafood, which are wonderful things to eat during the winter when there isn’t much other reliable food around.”
Last year, a team led by Professor Erik Trinkaus of the University of Washington in St Louis, USA. In the US, he published evidence showing that many Neanderthals suffered from a medical condition called “surfer’s ear.”
This condition is characterized by abnormal bone growths that appear in the ear canal. It is often seen in people who practice water sports in cold climates, but it can occur simply due to repeated exposure to cold and wet weather.
At the time the newspaper was published, there were suggestions that Neanderthals could have obtained it by sleeping in cold, damp cave floors.
“Moscerini’s archaeological evidence supports the idea of frequent exploitation of aquatic resources based on anatomical data,” Paola Villa and his colleagues write in the last article.
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