While the first human civilizations grew in Mesopotamia, and the ancient Egyptians were building the pyraminds, there were still woolly mammoths living on a remote arctic island. This is a pretty surprising fact. During the ice age, mammoths were common throughout Earth's northern hemisphere. But then their number declined.
This might have been due to the warming climate, or to human hunting, although evidence that humans hunted woolly mammoths is actually very limited. The animals were extinct in mainland Siberia and North America by about 12,000 years ago.
In spite of all of this, a few isolated populations hung on, stranded on arctic islands by rising sea levels. The last known woolly mammoths died on Wrangel Island, in the Arctic Ocean north of eastern Siberia, just 4,000 years ago.
Researchers are still trying to find out what finally killed them. A Eurasian team has reported studies comparing the chemical composition of fossil bones of mammoths from Wrangel Island with older ones from the Siberian mainland. Another American team compared the DNA sequence of a Wrangel Island mammoth with one from Siberia.
The chemical study showed that the mammoths didn't die out due to gradual decline in their food supply, but their water supply did become increasingly contaminated with heavy metals and other toxins. The genetic study showed that the small population of mammoths experienced an accumulation of detrimental mutations due to small numbers and inbreeding. In the face of these hardships, a short term crisis like a severe weather event might have caused their ulitmate demise.
Y: Can you believe it, Don? While the first human civilizations grew in Egypt and Sumer, and the ancient Egyptians were building the pyramids, there were still woolly mammoths living on a remote arctic island.
D: You’ve got to be kidding, Yaël. During the ice age, mammoths were common throughout Earth’s northern hemisphere. But, then their numbers declined. This might have been due to the warming climate, or to human hunting, although evidence that humans hunted woolly mammoths is actually very limited. The animals were extinct in mainland Siberia and North America by about twelve thousand years ago.
Y: Yes, but a few isolated populations hung on, stranded on arctic islands by rising sea levels. The last known woolly mammoths died on Wrangel Island, in the Arctic Ocean north of eastern Siberia, just four thousand years ago.
D: That’s amazing. Do we know what finally killed them?
Y: Researchers are trying to find out. A Eurasian team has reported studies comparing the chemical composition of fossil bones of mammoths from Wrangel Island with older ones from the Siberian mainland. Another American team compared the DNA sequence of a Wrangel Island mammoth, with one from Siberia.
D: So, what did they find?
Y: The chemical study showed that the mammoths didn’t die out due to gradual decline in their food supply, but their water supply did become increasingly contaminated with heavy metals and other toxins. The genetic study showed that the small population of mammoths experienced an accumulation of detrimental mutations due to small numbers and inbreeding. In the face of these hardships, a short term crisis like a severe weather event might have caused their ultimate demise.
