Nicholas Mrosovsky (3 March 1934 – 22 February 2015) was a Canadian zoologist known for his research in the fields of homeostasis, chronobiology, and sea turtle biology.
[3] With graduate student Janet Joy he found that endogenous circannual rhythms of body weight and molt in golden-mantled ground squirrels and in thirteen-lined ground squirrels could be delayed by cold temperatures in the spring,[4][5] suggesting that spring temperatures in nature can help synchronize the period of circannual rhythms in hibernators to an annual periodicity.
From these first forays into chronobiology, Mrosovsky's lab developed a productive research program on circadian rhythms, specializing on how golden hamster circadian rhythms of activity could be entrained or shifted by non-photic factors such as social interaction,[6] socio-sexual cues,[7] and novelty-induced wheel-running.
[9] The phase-shifting effects of strong behavioural arousal (as confirmed by running activity) is robust and further studies from the Mrosovsky lab showed that it in fact mediates the action of other stimuli on circadian rhythms, such as the benzodiazepine triazolam[10] and pulses of darkness given on a background of constant light.
He also contributed several entries to the News & Views column of the scientific journal Nature, and numerous editorials in Marine Turtle Newsletter.