Grolar Bear — Extinction By Any Other Name
In 2006, a hunter shot a bear in the Northwest Territories, Canada. This in itself was nothing unusual except that the bear in question didn’t look like any polar bear he had ever seen. It had white fur but also a humped back, particularly long claws and brown patches of fur around its eyes.
A DNA test from a lab in British Columbia revealed the mysterious bear was actually a hybrid of a polar and grizzly bear — the first of its kind to be found in the wild, though specimens had been born in captivity. In the same style of nomenclature as other hybrids, the bears were christened “grolar bears” as in ligers, tigons and coywolves. Four years later, another hunter shot what he thought was a polar bear, only to find that something didn’t look right. Testing showed it to not only be a hybrid, but the result of a polar/grizzly mother and grizzly bear father, demonstrating that unlike many hybrids, polar and grizzly bears produce fertile offspring.
This sounds cool — and, to be honest, it kind of is. The potential for a new species is fascinating, especially among megafauna such as bears, let alone the two largest living species. The troubling aspect is the speed at which it’s happening and what it means for our planet and species diversity.
In evolutionary terms, polar bears evolved fairly recently when they split off from grizzly bears, so it’s not inconceivable that hybrids would occur in the wild (hybrids have been produced in zoos before). Species merge and diverge in reaction to massive — but gradual — changes in the environment that act as a catalyst, on the scale of shifting continents and changing climates.
In this case, the catalyst is climate change — something that’s happened naturally before but is now occurring at unheard of speeds. What should have taken centuries is taking decades, as the sea ice melts and polar bears are forced south from their traditional arctic hunting grounds.
People assume extinction happens only one way — through a species dying off. Hybridization is more subtle but when a less populous species (polar bears) begins to interbreed with a greater one (grizzly bears), eventually the smaller one will be completely assimilated.
It’s not exactly what comes to mind at the word ‘extinction’ but the loss to genetic diversity (something already decreasing at a frightening rate) is the same and the species is gone. Since the hybridization is happening far more rapidly than it should, it will leave a gap in the Arctic ecosystem, where polar bears are apex predators.
Whereas the coywolves that I wrote about earlier are stepping in to take the place of wolves in the northeastern United States, there’s no guarantee that the hybrid grolar bears would be able to fill the same critical niche. The absence would cause a cascade effect on a number of other species — ourselves included.
While a photo of a grolar bear might not be quite as obvious as one of an emaciated, starving polar bear, hybridization is just as much a symptom of the species’ path towards extinction.
