Daily body temperature rhythms persist under the midnight sun but are absent during hibernation in free-living arctic ground squirrels

• Published in: Biology Letters
• Main Authors: Williams, Cory T., Barnes, Brian M., Buck, C. Loren
• Format: Text
• Language: English
• Published: The Royal Society 2012
• Subjects: Animal Behaviour; Arctic; Burrows; midnight sun
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3259947; http://www.ncbi.nlm.nih.gov/pubmed/21752811; https://doi.org/10.1098/rsbl.2011.0435

In indigenous arctic reindeer and ptarmigan, circadian rhythms are not expressed during the constant light of summer or constant dark of winter, and it has been hypothesized that a seasonal absence of circadian rhythms is common to all vertebrate residents of polar regions. Here, we show that, while...