Quick, which event happened first: the building of the Great Pyramid of Giza, or the death of the last woolly mammoth? The Great Pyramid was around for hundreds of years before the last mammoth died out. While mammoth populations began disappearing around 15,000 years ago due to climate change, the population of mammoths on Wrangel Island in the Arctic Ocean held on until 4,000 years ago, when they died fairly suddenly. So why did the Wrangel Island mammoths live so much longer?
The team of researchers from Finland, Germany and Russia examined the isotope compositions of carbon, nitrogen, sulfur and strontium from a large set of mammoth bones and teeth from Northern Siberia, Alaska, the Yukon, and Wrangel Island, ranging from 40,000 to 4,000 years in age. The aim was to document possible changes in the diet of the mammoths and their habitat and find evidence of a disturbance in their environment. The results showed that Wrangel Island mammoths’ collagen carbon and nitrogen isotope compositions did not shift as the climate warmed up some 10,000 years ago. The values remained unchanged until the mammoths disappeared, seemingly from the midst of stable, favorable living conditions.
This result contrasts with the findings on woolly mammoths from the Ukrainian-Russian plains, which died out 15,000 years ago, and on the mammoths of St. Paul Island in Alaska, who disappeared 5,600 years ago. In both cases, the last representatives of these populations showed significant changes in their isotopic composition, indicating changes in their environment shortly before they became locally extinct.
That opens up another question: why did the Wrangel Island mammoths go extinct? We do not have a definitive answer, but we do have a few possible explanations, which you can read about at the University of Helsinki. -via Kottke
(Image credit: Miss Barabanov)