Body orientation of sheep in herds

Abstract

Certain physical environmental factors such as temperature, wind, solar radiation, and magnetic field have been documented as modulators of body orientation in mammals. This study aims to analize the body orientation of sheep in herds and its possible relation with the aforementioned factors. We recorded the orientation of 1155 animals in several areas in province Segovia (central Spain) under different conditions regarding temperature, relative position of the Sun and presence/absence of clouds and wind. For analyzing data, we used circular statistics. The results do not allow us to conclude that orientation of sheep depends on temperature and wind direction, but suggest a magnetic alignment: when there was no wind nor sun (overcast days), the V-Test showed a preferred orientation NE-SW that could be attributed to alignment with the magnetic Earth field. These results are consistent with the obtained for other mammals, both herbivores and carnivores, and suggest this common alignment could provide to them some advantage related to certain biological processes.