The offspring of a male donkey and a female horse is a mule – the opposite is a hinny. The offspring of a male lion and a female tiger is a liger – the opposite is a tigon. The offspring of any polar bear and any grizzly bear is a pizzly – and a paleontologist and associate professor of biological sciences says this hybrid is becoming more common and could help starving polar bears survive climate change.
“We were really surprised that polar bears consumed soft foods, even during the Medieval Warm Period, a previous period of climate change that occurred approximately 1,000 years ago.”
By soft foods, Vanderbilt University paleontologist and professor Larisa DeSantis means seals, which are becoming harder for polar bears (Ursus maritimus) to hunt as Arctic warming reduces the amount of sea-ice they need. As a result, more photos are appearing of starving polar bears, which generate sympathy but little real activity and change to resolve their plight before they become extinct. According to her new study published in the journal Global Change Biology and summarized in a Vanderbilt press release, DeSantis used dental microwear texture analysis to study microscopic wear on tooth surfaces of current polar bears and 1,000-year-old skulls in museums to determine what today’s polar bears are eating and if they’ve changed their diets to compensate for less available seals. Just as during the Medieval Warm Period, they’re still stuck on soft seal flesh and fat which better suits their smaller, elongated skulls, jaws and teeth. However, those same narrow skulls prevent them from eating tougher foods.
Fortunately, starving bears can still mate. As they retreat inland from receding ice, they’re meeting up with grizzly bears (Ursus arctos) from Canada and the U.S. moving north because of – you guessed it – climate change which is warming their territory and forcing them northward to seek cooler climes. The Daily Mail points out that grizzly bears are better adapted to eat hard foods like plant tubers or to scavenge carcasses of caribou, moose and other non-marine animals. Driven by nature to seek healthy partners, polar bears are mating with grizzlies to bear pizzlies -- which were first seen in the wild in 2006 and have a mostly white coat with a brownish hue, and a nose that is the best of both bears. Better yet, they carry the gene of polar bears and may help them come back after (assuming there is an after) climate change is over.
Will hybrid pizzlies save the polar bear? DeSantis seems to think it can’t hurt.
“Unfortunately, history and pre-history repeats itself. Highly specialized sabertooth cats went extinct at the end of the Pleistocene. Only animals that were already generalized or able to adapt survived. Specialists like the polar bear are at greater risk of extinction, especially if their habitat is literally melting away.”
Pizzly is a cute name and the hybrid bears are definitely generalists who can adapt to this new environment. Should we humans accept that as inevitable and not try to save the polar bears through conservation and reducing climate change?
If we don’t, the ice and polar bears may not be the only things that will literally melt away.