WE ALL KNOW ABOUT RISING TEMPERATURES AND MELTING ICE CAPS, BUT WHOEVER HEARD OF THE GROLAR BEAR? HERE ARE SOME OF THE LESSER-KNOWN IMPACTS OF CLIMATE CHANGE
Hayley Bennett is a freelance science writer based out of Bristol, UK. In this issue, she talks about the real effects of climate change.
Some say ‘grolar’, others prefer ‘pizzly’. Whichever it is, this grizzly-polar bear cross, or hybrid, is the result of two habitats colliding under the influence of climate change. While melting sea ice is forcing the remaining polar bears ashore, the previously frigid Arctic is becoming increasingly bearable to grizzlies venturing north.
Encounters with grolar bears – including one shot by a hunter in northern Canada in 2016 – seem to be on the rise, suggesting the two species may be mating more often. The hybrid bears are fertile, so there’s been talk of a new species emerging. However, Dr Andrew Derocher, a bear biologist from the University of Alberta, Canada, doubts this will happen. “Predicting evolution is a fool’s game,” he admits. “However, my best guess is that we won’t see a new species. Grizzly bears could easily absorb a bit of polar bear DNA and keep on going.” In fact, he adds, grizzlies in some of the islands off the north coast of Venezuela have carried DNA from polar bears since polar bears were further south tens of thousands of years ago. A 2017 study suggests that hybrids prefer to mate with grizzlies over polar bears, which should protect the polar genome – though polar bears themselves may die out. Other climate-driven crosses include a number of different seal hybrids, as well as beluga-narwhal whales spotted in western Greenland.