Scientists discover why giant human-size beavers have disappeared

The giant beaver measured about 2 meters long and weighed up to 100 kg once traveled in North America.

However, towards the end of the last ice age, the mega-rodents disappeared. Their extinction coincided with the disappearance of other large animals, including the woolly mammoth.

However, until today, scientists did not know how exactly the giant beaver was extinct about 10,000 years ago.

Giant Beavers in North America

The giant beaver was considered a very successful species. Scientists have discovered fossil remains of mega-rodents in North America, from Florida to Alaska and the Yukon.

In terms of appearance, the giants of the Ice Age are very similar to modern beavers, but with two crucial differences. Instead of their paddle-shaped tails, giant beavers had long, lean tails like those of a muskrat. Animals now extinct also had larger, curved anterior teeth, not the sharp, chiseled incisions of their modern counterparts.

Why giant beaver died 10,000 years ago

To better understand the giant beaver, especially the cause of its extinction, the researchers studied the fossil remains of mega-rodents. Using stable isotope ratios from bone and ancient teeth, the team determined the diet and behavior of the creatures.

"Basically, the isotopic signature of the food you eat is incorporated into your tissues," explained Tessa Plint, a graduate student and one of the authors of a study published in Scientific reports. "Since the isotopic ratios remain stable even after the death of the organism, we can examine the isotopic signature of the fossil materials and extract information about what this animal ate, even if that animal was living and dying there are tens thousands of years. "

The study found that unlike modern beavers, giant beavers did not cut or eat trees. They preferred to eat aquatic plants.

"Giant beavers were not" ecosystem engineers "like the North American beaver," said Plint.

Previous studies had suggested that giant beaver preferred warmer and wetter environments. Their fossil remains were most often found in sediments from ancient wetlands.

Their dependence on wetlands for their habitat and food has caused them to fall. According to Plint, when the ice sheets retreated after the last glacial maximum, about 10,000 years ago, the climate became drier and giant beavers disappeared.

The smaller, modern beavers, however, have survived climate change through their ability to build dams and shelters. Unlike larger species, modern beaver can alter any environment and make it a more suitable habitat.

The results corroborate the claim that climate change and human impact caused the extinction of megafauna at the end of the last ice age.

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