Million of years ago Grizzlies and Polar Bears shared the same DNA; now climate change has reunite them in one new species.
Climate change has had very serious consequences throughout the planet; hundreds of species have had to migrate to different habitats due to the devastation of their ecosystems. Polar bears have been perhaps the most affected by the melting of glaciers and have had to move to other regions. Thus, in the convergence between a polar bear and a grizzly bear, a new species called grolar emerged, which is a hybrid between the two.
The melting of the polar ice caps is undoubtedly one of the most urgent climate emergencies the planet is going through. Just a few days ago, the world’s largest glacier, the A-68 that broke off from the Larsen-C shelf in 2017, in the Antarctic Peninsula, was declared extinct. But this emergency is not only limited to the South Pole; the Arctic is also experiencing the melting of its ice bodies.
The most immediate consequence is that the endemic species of the poles move to other regions in search of food. The polar bear, as a consequence of the lack of habitat, has migrated to the northern tundras, where it has converged with the grizzly bear, the result is that a new species, called grolar, has emerged from the crossing of both species.
Expansion of the grolar bear
As the polar bear moves into more southerly regions, it has new interactions with the grizzly bear, as a consequence the offspring between the two, i.e. the grolar, is expanding more and more.
Researchers have been following this case closely. The situation is worrisome since hybrid species tend to be more vulnerable in their new habitat; they are generally known to be no better adapted to their environments than their parents. But grolars appear to be an exception, the characteristics of both bear species seem to give them an advantage over other species. Experts say that this species of hybrid bears are probably more resistant to temperature changes in the environment.
Larisa DeSantis, a paleontologist, and professor of biological sciences at the University of Tennessee explains that grolars are here to stay. Their skulls are more elongated than those of their progenitors, allowing them to catch prey more easily in the sea. However, they also have a disadvantage: their molars are too small compared to those of the grizzlies. This conditions them to eat only fat, unlike the browns, which are also omnivores.
Strangely enough, the two species of polar bear and grizzly, which have resulted in the grolar, were once the same. However, they separated about half a million years ago also as a result of climatic changes. This made it possible for them to have DNA similarities that now, thousands of years later, unite them again in a new hybrid species.
Text courtesy of Ecoosfera