Bear

Bears were a lifeform native to Earth.

The men of the Tribe of Gum hunted bears for their warm skins. (DW: An Unearthly Child)

In the year 5000, outside Brittanicus Base, Jamie and Elric Penley were attacked by a bear. Penley succeeded in tranquilising it, but was badly injured while doing so. (DW: The Ice Warriors)

During a mission for Santa Claus, the Doctor encountered and was menaced by a polar bear, but was rescued by John and Gillian, who used the Doctor's model-making machine to reduce the bear to miniature size. (TVC: A Christmas Story)

Horned bears were among the native lifeforms of Tiermann's World. (NSA: Sick Building)

On Hyspero, Angela ruled over the bears of Kestheven, who shaved their golden fur and went about hairless. (EDA: The Scarlet Empress)

Life forms which seemed to be descended from bears or bear-like creatures included Aggedors and Ursines.