Welcome to Brainstuff, a production of iHeart Radio, Hey brain Stuff Lauren Vogelbaum. Here, if we picture the demise of the wooly mammoths, we might think of a herd of shaggy elephants pursued by prehistoric humans, spears in hand and dinner on the brain. And that may well be how the vast majority of the massive herbivores met their fate.
But a study published in the journal Proceedings of the National Academy of Science reports that one of the world's final populations of wooly mammoth's was ultimately killed by a lack of fresh drinking water. It's long been thought that most of the world's wooly mammoth populations when extinct due to a combination of climate change and human hunting, with the last of their kind dying off on the mainland around eleven thousand years ago, but a few stragglers held on.
For instance, one population survived until about four thousand, three hundred years ago on a remote chunk of Arctic land. The study in question dates the end of another nearby group to five thousand, six d and fifty years ago, give or take eighty years. The mammoths of Saint Paul Island in the Bearing Sea between today's Russia and the United States. The discovery is being touted as the most
accurately dated prehistoric extinction to date. As the post Ice Age world warmed and sea levels rose, it seemed that Saint Paul Island shrank in area, and its freshwater lakes that sustained mammoths became scarcer. The researchers discovered something of a domino effect, as more mammoths and other animals crowded around fewer freshwater sources and trampled more vegetation around the lakes.
This contributed to an increase in dirt and sediment flowing into the lakes, making what little water remained even less suitable for drinking. In response to similar situations, modern day elephants have been seen digging holes near to a sediment filled lake in search of clean drinking water, a short term fix, but one where the earth dug up muddies
the primary lake even more. The Asian elephant is the wooly mammoth's closest living relative, though, if you were picturing a group of towering mammoths, true to their names, staggering around in search of drinking water. Tweak that image a bit. The offshoot populations of wooly mammoths like those on St. Paul were dwarf descendants of the mainstream wooly mammoth. They were only a little taller than a full grown human.
Thanks to generations of inbreeding and evolutionary responses to island environments, the scientists were able to discern how the lake environment changed by analyzing core samples extracted from the lake bed. They also tracked the change over time in fungal spores known to grow in the dung of large mammals like mammoths.
They're particularly confident in the environmental aspect of their conclusions because the island became isolated from the mainland about fourteen thousand years ago, and there's no evidence humans ever lived there and affected the mammoth population. The first humans to step foot on island arrived by boat in seven CE. Today's episode was written by Christopher Hasseiotis and produced by Tyler Clang. For more on this and lots of other mammoth topics, visit how stuff works dot com. Brain Stuff
is production of I Heart Radio. For more podcasts for my Heart Radio visit the I heart Radio app, Apple podcasts, or wherever you listen to your favorite shows.