Asian black bear
Biologically and morphologically, Asiatic black bears represent the beginning of the arboreal specializations attained by sloth bears and sun bears. Asiatic black bears have karyotypes nearly identical to those of the five other ursine bears, and, as is typical in the genus, they have 74 chromosomes. From an evolutionary perspective, Asiatic black bears are the least changed of Old World bears, with certain scientists arguing that it is likely that all other lineages of ursine bear stem from this species. Scientists have proposed that Asiatic black bears are either a surviving, albeit modified, form of "Ursus etruscus", specifically the early, small variety of the Middle Villafranchian (Upper Pliocene to Lower Pleistocene) or a larger form of "Ursus minimus", an extinct species that arose 4,000,000 years ago. With the exception of the age of the bones, it is often difficult to distinguish the remains of "Ursus minimus" with those of modern Asiatic black bears.
Brown bear
While the brown bear's range has shrunk and it has faced local extinctions, it remains listed as a least concern species by the International Union for Conservation of Nature (IUCN) with a total population of approximately 200,000. , this and the American black bear are the only bear species not classified as threatened by the IUCN. However, the California, North African and Mexican subspecies were hunted to extinction in the 19th and early 20th centuries and many of the southern Asian subspecies are highly endangered. One of the smaller-bodied subspecies, the Himalayan brown bear, is critically endangered, occupying only 2% of its former range and threatened by uncontrolled poaching for its body parts. The Marsican brown bear, one of several currently isolated populations of the main Eurasian brown bear population in central Italy, is believed to have a population of just 30 to 40 bears.