Polar Opposites

On a recent safari, some guests asked me “what is the largest land dwelling carnivore on the planet”? This is the polar bear (Ursusmaritimus). These amazing creatures live in and around the Arctic Circle, and are amazingly adapted for their way of life.

From this question, we got discussing if there were ever any bear species that lived in Africa. Surprisingly the answer was yes. The Atlas Bear (Ursusarctoscrowtheri),which is a subspecies of the Brown Bear, was the only bear native to Africa.It inhabited the Atlas Mountains and it was distributed in North Africa from Morocco to Libya, but has been extinct since around the 1870’s. Thousands of these bears were hunted for sport, or used for execution of criminals following the expansion of the Roman Empire into North Africa. The last known specimen was probably killed by hunters in the 1870’s in the Rif Mountains of northern Morocco.The Atlas bear was brownish black in colour, and lacked a white mark on the muzzle. The fur on the under parts was reddish orange. The muzzle and claws were shorter than that of the American black bear, though it was stouter and thicker in body. This can be attributed to the adaptations of each bear for habitat and feeding. Black bears climb trees and need a stronger sense of smell, hence the longer muzzle for smelling and longer claws for climbing.The Atlas bear would need to be stouter as the mountainous terrain it lived in would mean it would need to be more compact to travel longer distances for food, and would not need longer claws to climb trees. It apparently fed on roots, acorns and nuts, and occasionally hunted mammals. The most widespread species is the Brown Bear, which occurs from Western Europe eastwards through Asia to the western areas of North America. The American Black Bear is restricted to North America, and the Polar bear is restricted to the Arctic Sea. All the remaining species are Asian.

What makes this topic interesting is how bear species are distributed around the planet, and are notably absent form Sub Saharan Africa. It is thought that ancestors of the Atlas bear were found south of the Sahara, but when the Sahara formed thousands of years ago, it basically made an impassable obstacle for most mammal species. This meant that species could not move from north to central Africa to escape the growing desert. These bear species gradually died out as they could not adapt to the sudden climate and habitat change, and as such became extinct. This is a similar occurrence discussed in previous blog articles on the big cats, and how distribution and speciation was regulated by climate, shifting continents and habitat change. These are the main drivers to what mammal species we have on the planet today, and their current distributions.If you ever get the chance to travel to areas where bears are present, take the chance with both hands. I have had numerous guests and colleagues return from trips blown away by the sheer immense proportions of these animals, and the amazing behavior they got to witness.Do you have an question for Chris? Drop us a line in the comments, about polar bears or anything else!