Researchers had always believed that Neanderthals, the predecessors to modern humans, had not been very smart. However, recent evidence has led them to think otherwise - Not only did the stocky hunters build complex tools, but also, spoke a language and even, buried their dead. Now it turns out, they may also be responsible for some of Europe's oldest cave art.

This latest revelation is based on the results of a study conducted by a team of scientists led by University of Bristol's Alistair Pike and University of Barcelona's Joao Zilhao, and involved using a new technique to date more precisely, the ancient artwork found inside 11 caves in Northwestern Spain- Something that has been difficult to do because the currently used radiocarbon dating method does not work well on paintings with mineral pigments, engravings or those over 35,000 years old.

Instead of dating the paintings directly, the two decided to use the Uranium-Thorium method to date the thin film of calcium carbonate crystals that cover cave walls. In use since the 1960's to determine the date of the calcium carbonate crystals that make up stalagmites and stalactites found in ancient caves, it measures how much of the Uranium that is present in the crystals is still radioactive versus how much of it has been decayed to its end product - the non radioactive Thorium. Since Uranium decays at a steady rate, the technique is considered to be extremely accurate.

Because the traditional method requires hundreds of grams of calcium carbonate, this technique had never before been contemplated to date cave artwork. However, Pike and Zilhao figured out a way to modify it, such that it works even with even a tiny granule of calcium carbonate.

While the team used this method to date over 50 drawings in the various caves, they were particularly interested in the results of the more abstract ones, like hand stencils or a red disk that had been discovered in one of the caves. Their hunch proved right - The date of the deposits of those ranged from 37,500 years all the way back to 40,800 years, making the artwork they covered even older than that found inside France's Chauvet Caves, which is believed to be between 32,000 to 37,000 years old.

However, what makes this discovery even more interesting is that the calcium crust takes years to build up. This means that the paintings must have been completed many years prior to that - Making it a strong possibility that the cave art was not the work of us modern humans, but our predecessors, the Neanderthals that had arrived in Europe about 250,000 years ago and lived there up until 50,000 years ago.

Though Pike and Zilhao, who published their findings in the Journal of Science earlier this month are convinced this is the case, other experts are not so sure. They believe that the Neanderthals had already begun to migrate to the Southern part of Europe around this time, and that the cave art was the work of the early humans that had started to arrive from Africa.

More art from this period will have to be discovered for the world to be thoroughly convinced. But, if the two researchers are right, it adds to the growing evidence that the Neanderthals that roamed Europe long before the arrival of the early modern human, were much smarter than we have been giving them credit for.

Resources: history.com, csmonitor.com,