Ever since the early 1700s, when scientists such as Irish physician and collector Hans Sloan began studying the fossilized teeth and tusks of Siberian woolly mammoths, researchers have debated what caused the demise of these Ice Age behemoths. Furry cousins of modern elephants, mammoths stomped their way across northern Eurasia and North America beginning 300,000 years ago. But between roughly 10,000 and 20,000 years ago, all except a few isolated island populations disappeared. Scientists believe the last of them may have died on Russia’s Wrangel Island in the Arctic around 1700 B.C.