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Polar bears have lived through climate change before, can they again?

According to a new study, polar bears have lived through climate change before. Can they do it again?

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A new study suggests the polar bear species may be four million years old. (Thomas Niedermueller/AFP/Getty Images)

Polar Bears have seen climate change before. According to a new genetic study on the white-coated arctic mammal, the polar bear species might be upwards of four million years old. 

Webb Miller of Pennsylvania State University, along with a group of researchers, set out for the task of finding out just how old the species is to hopefully help them understand how the bears might have survived before. In a study published in Proceedings of the National Academy of Science, Miller said there is no guarantee that polar bears will make it through climate change this time. 

Miller noted that polar bears were likely able to survive other drastic climate changes because of their genetic diversity. He also told Scientific American that the bears are facing unprecedented threats such as heavy metal pollution accumulating in the Arctic. 

The group produced simulations of how the polar bear's DNA changed over time. Their findings suggest that the polar bear populations rose and fell with the temperature, according to Science News. After thriving during cooler times between 800,000 and 600,000 years ago, the bears, "seem to have suffered a genetic bottleneck and crashed after a warmer period that started about 420,000 years ago," Science News noted.

Charlotte Lindqvist of the University at Buffalo, told The New York Times, that during these times of warming, polar bears would often breed with brown bears who moved north during warming, potentially helping the species to survive the rising temperatures. 

The authors of the study suggested that there may be more inbreeding ahead for brown bears and polar bears, giving the polar bears a fighting chance against climate change. 

More from GlobalPost: Polar bears in Alaska losing fur, scientists say

http://www.globalpost.com/dispatch/news/science/120724/polar-bears-climate-change-can-they-again