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.
Asian black bear
In Russia, the black bear's northern range runs from Innokenti Bay on the coast of the Sea of Japan southwest to the elevated areas of Sikhote Alin crossing it at the sources of the Samarga River. At this point, the boundary directs itself to the north, through the middle course of the Khor, Anyui and Khungari rivers, and comes to the shore of the Amur, crossing the it at the level of the mouth of the Gorin. Along the Amur river, the species' presence has been noted as far as 51° N. Lat. From there, the territorial boundary runs southwest of the river's left bank, passing through the northern part of Lake Bolon and the juncture point of the Kur and Tunguska. Black bears are encountered in the Urmi's lower course. Within the Ussuri krai, the species is restricted to broad leaved Manchurian type forests.