Entheseal Changes in Free-Ranging Versus Zoo Reindeer-Observing Activity Status of Reindeer

We evaluate whether entheseal changes (EC) can be used to reconstruct activity among reindeer to study its domestication. Humans influence reindeer activity patterns through corralling, which renders them less mobile than free‐ranging reindeer and through use as draught animals, which can result in overuse of certain muscles. There is also variation within free‐ranging reindeer in baseline activity levels due to environmental factors. Other sources of variation at entheses include age, sex, pathology, size, and genetic disposition. Here we examine if there are differences in the entheses between zoo versus free‐ranging reindeer. We recorded the entheses of reindeer long bones using a modified EC scoring system. Weight effects were accounted for by performing analyses separately for specimens under and over 95 kg, but unfortunately age information was lacking. We found that several flexor muscle insertion sites in the ulna were more developed among free‐ranging reindeer. This difference is likely due to feeding behaviour. The free‐ranging animals were digging for lichen from under the snow whereas the zoo reindeer were fed by their keepers. This difference in entheses, however, was found to be significant only among the heavier reindeer. Among the zoo reindeer, the insertion for Subscapularis muscle was more developed, possibly due to increased time spent immobile with the shoulder‐bracing muscle apparatus activated. This difference was significant among the heavier deer and nearly statistically significant among the lighter weight reindeer. Domesticated Siberian draught reindeer fell between zoo and free‐ranging reindeer in several tibial entheses. According to these results, some forelimb entheses may be useful to study differences in mobility and feeding patterns between groups of reindeer. Copyright © 2014 John Wiley & Sons, Ltd.