Gibraltar Special
Gib scientists say climate change finished off southern Iberia’s Neanderthals
Brian McCann
A paper co-written by experts from the Gib museum claims the Rock was a final refuge
A paper in the prestigious international ‘Quaternary Science Reviews’, provides strong evidence in favour of the view that the Neanderthals became extinct as a result of climate change.
Scientists from Gibraltar Museum teamed up with colleagues from the University of Granada, Stanford University in California and the Institute for Research on Earth Evolution in Yokosuka (Japan) to correlate the human presence in southern Iberia between 40 and 20 thousand years ago, with detailed climatic data for that period obtained from a deep-sea sediment core taken in the Balearic Basin.
The paper, entitled ‘Climate forcing and Neanderthal extinction in southern Iberia: insights from a multiproxy marine record’, reveals that conditions in southern Iberia became highly inhospitable around 24 thousand years ago. The Neanderthal extinction appears to be linked to these extreme conditions, which, the scientists say, were the most severe in this part of the world for a quarter of a million years.
An armada of icebergs reached the Portuguese coast, and the lowest annual mean sea surface temperatures (calculated at around eight degrees Celsius) for a quarter of a million years were reached in the Strait of Gibraltar and the Alborán Sea. It appears that the cause was a combination of the rearrangement of current circulation and reduced solar radiation caused by changes in orbital geometry. On land, many continental areas of southern Iberia became arid and dominated by steppe plants. Linked to this is evidence of an increased input of wind-blown sand which appears to be related to the amplified aridity at that point.
Overall conditions were severe but also highly variable at short time scales and this seems to have affected many stressed populations of animals as well as the Neanderthals, whose last refuge were the caves in the Rock of Gibraltar. The climate changes also caused a significant readjustment of modern human populations. Some traditional modern human cultures also disappeared and the emergence of a new human culture, the Solutrean, coincides with this climatic event. It now seems clear that rapid climate change not only caused the demise of the last Neanderthals on the planet but that it also generated significant cultural transformations among modern human groups. Those who managed to scrape past this event were our ancestors.
Clive Finlayson, Geraldine Finlayson and Darren Fa of the Gibraltar Museum are co-authors of this paper.
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