Hair structure of brown bears ( Ursus arctos L.) from North America and Scandinavia

• Published in: Canadian Journal of Zoology
• Main Authors: Elgmork, K., Riiser, H.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1991
• Subjects: Animal Science and Zoology; Ecology, Evolution, Behavior and Systematics; Ursus arctos
• Online Access: http://dx.doi.org/10.1139/z91-337; http://www.nrcresearchpress.com/doi/pdf/10.1139/z91-337

Analysis of measurements of guard hairs from North American brown or grizzly bears and Scandinavian brown bears (Ursus arctos L.) showed variation over the body and along the hair shaft. Using the medullary index, i.e., the medullary diameter as a percentage of the hair diameter, comparisons were made among body areas, age groups, geographical areas, sexes, and seasons. Statistically significant differences were found among body areas. Hairs from the foreleg were shorter and wider, with a smaller medullary index than those from other body areas. There was a weak but statistically significant negative correlation between the medullary index and age of individuals. Medullary indices from Scandinavian bears were significantly greater than those from Alaskan bears, which in turn were greater than those from bears of the contiguous United States. There were no statistically significant differences between the medullary index and sex or season.