Early Polar Bears

Ursus maritimus tyrannus (Latin for tyrant sea bear) was recognized as the first subspecies of polar bear in 1964 by Björn Kurtén. Fossils were found at the gravels of the Thames at Kew Bridge, London, England. It is believed to have evolved between 250,000 and 100,000 years ago when a large number of Siberian brown bears became separated by glaciers.

HABITAT
The habitat of the early polar bear started out as far south as England and the northern coast of Spain. As they moved farther and farther north, they adapted to the harsh environment of the Arctic.

CHARACTERISTICS
Tyrannus was markedly larger and more Arctos-like than the present polar bear. Their bone structure was similar to that of brown bears only much larger. They measured about 6 feet at the shoulder, over 12 feet in length, and weighed on average over 2,500 pounds making it the largest carnivorous land mammal ever.

DIET
Though the diet of this early polar bear isn't really known, one can probably assume that it started out pretty much like that of the Siberien brown bear, and became more and more like that of the modern polar bear, adopting a more specialized and carnivorous diet. Its size and strength would have allowed this bear to take down large animals like buffalo and woolly mammoths. However, it would have also been capable of running any predators away from their kill, allowing it to be a scavenger.

EVOLUTION
Ursus maritimus tyrannus, was essentially a brown bear subspecies with many brown bear features. This group of Siberian bears from which they evolved is believed to have quickly decreased in number as a result of selective pressures allowing survival only to those capable of adapting to the changing environment. To adapt to the Arctic, they developed a dense, white, oily coat to camouflage them and repel water. Their carnivorous diet provided them with a thick layer of body fat which gave them insulation and buoyancy. Their paws became larger and partially webbed to use as paddles in the water. To emit as little heat as possible, their ears and tail became smaller. Eventually, these early polar bears evolved into the modern polar bears of today.

Wolves Of The World Banner

| Home | Agriarctos | Agriotherium | Alaskan Grizzly | Allocyon loganensis | Argentine short-faced bear |

| American Black Bear | Asiatic Black Bear | Atlas Bear | Auvergne Bear | Baluchistan Black Bear |

| Brown Bear | Cinnamon Bear | California Black Bear | Dall Black Bear | Dawn Bear | Early Polar Bear |

| Etruscan bear | European Cave Bear | Florida Black Bear | Florida Cave Bear | Formosan Black Bear |

| Giant Panda Bear | Giant Short-Faced Bear | Grizzly Bear | Himalayan Black Bear | Indarctos arctoides |

| Japanese Black Bear | Kamchatka Brown Bear | Kermode Bear | Kodiak Bear | Kolponomos |

| Olympic Black Bear | Parictis | Plionarctos | Polar Bear | Primal Panda Bear | Protursus |

| Pygmy Giant Panda | Qinling Panda Bear | Siberian Brown Bear | Sloth Bear |

| Spectacled Bear | Sun Bear | Syrian Brown Bear | Tibetan Blue Bear |

| Ursus abstrusus | Bear Subspecies / Classification | Bear Links |

Bears Of The World
© 1999-2024
All rights reserved.