Brown bear (Ursus arctos L.) of the Northern Urals in the late neopleistoceneand holocene.

The article describes the distribution and changes of brown bears size characteristics in the Northern Urals during the Late Neopleistocene and Holocene. The material from 19 localities has been used in this work. The materials of the first half of the Late Neopleistocene include more significant quantity of brown bears remains than the materials of the second half of the Late Neopleistocene. This fact reflects a rather high number of bears in this period that is probably due to a relatively warmer and more favorable climate in this period. Individual remains of brown bear bones were found in materials of the second half of the Late Neopleistocene. Such rare bear remains in materials of the second half of the Late Neopleistocene indicate a very low number of this species in nature at this time due to cold climate conditions when suitable (forest) habitats for bear preserved only along the river banks. On the western slope during the maximum cold stage of the Late Neopleistocene brown bear remains were not found. While on the eastern slope abrown bear lived during the whole Late Neopleistocene. In the materials of the Middle and Late Holocene numerous brown bear remains were found. Unfortunately we do not almost have the materials of the Early Holocene. Probably, due to the increase in taiga forests area in this period the brown bear number was as high as in the later periods of the Holocene.There is sexual dimorphism of brown bear in size of P4/ and P/4, M1/ and M/1. Teeth of males are longer than teeth of females. Despite the fact that average values characteristics differ, there is quite a significant transgression. There are fossil teeth from individuals of both sexes in all samples. When we compared these samples, we took account of average values as well as the range of variability attributes. The differences between fossil samples were considered significant if limits variability characteristics of these samples were shifted relatively to each other and the differences of their average values were greater than differences of average values between male and female samples. An analysis of the dimensional characteristics of the brown bear showed that in the first half the Late Neopleistocene in the Northern Urals there lived the brown bear with very big teeth whose dimensions are comparable to those of U. a. priscus from the Late Neopleistocene of the Western Europe. During the second half of the Late Neopleistocene and possibly early Holocene the size of teeth and mandible of brown bear reduced gradually. Parameters of the mandible and the teeth of the bear remained constant from the Middle Holocene to the modernity.

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