Durham University studies causes of mammoth extinction
Aug 18 2010 by Tony Henderson, The Journal
The decrease in productivity and extent of grassland is likely to have been the major contributor to the extinction of many large mammals across most of northern Eurasia and north-western North America by about 11,400 years ago, the onset of the present warm interglacial period. Although some species held on for several thousand years longer in very limited localities, their fate had effectively been sealed.
Professor Brian Huntley, from the School of Biological and Biomedical Sciences at Durham University, said: “Woolly mammoths retreated to northern Siberia 14,000 years ago whereas they had roamed and munched their way across many parts of Europe, including the UK, for most of the previous 100,000 years or more. The change from productive grasslands across large areas of northern Eurasia, Alaska and Yukon to less productive tundra-like habitats had a huge effect on many species, particularly on the large herbivores like the woolly rhinoceros and woolly mammoth.
“Mammoths and other mega-mammals found it increasingly difficult to find food.
“We believe that the loss of food supplies from productive grasslands was the major contributing factor to the extinction of these mega-mammals.”
The Durham University-led team included scientists from the Natural History Museum, London; Lund University, Sweden and Bristol University.
Their study found the post-glacial warming of the planet coupled with an associated change to a moister climate and with increased levels of carbon dioxide in the atmosphere, resulted in the proliferation of trees and the subsequent decline in grasslands – the staple diet and fodder of large herbivores. The decline in herbivores had knock-on effects for other parts of the food chain.
Experts say the new evidence of massive habitat change linked to climatic change is a parable for modern times.
Prof Huntley said: “This was a time of major environmental change and losses of habitat that may have led to the extinction of herbivores and other mega-species that roamed many parts of the planet.
“This is a model for what may happen as a result of rapid climate change over the next century linked to human activity. It is food for thought in these times of global warming and human-induced habitat change. There may well be a lesson to learn.”
