RUI: Physiology of Sleep and Assessment of the Costs of Experimental Sleep Loss in Arctic-Breeding Songbirds

Western Kentucky University Research Foundation, Bowling Green KY

Investigators

Abstract

Sleep is an essential and restorative process that is often neglected in modern society. In humans, chronic sleep loss (insomnia, shift work, sleep apnea) has negative consequences on normal physiological and mental function and is a risk factor for many chronic conditions, such as metabolic and cardiovascular diseases. In the Arctic, migratory songbirds are active for 20 hours/day to take advantage of constant summer light, and seemingly do not suffer from the well-known detrimental effects of sleep loss, such as physiological and cognitive dysfunction. This research aims to investigate sleep patterns and assess the costs and benefits of sleep loss in arctic-breeding songbirds in Barrow, Alaska (71°N). Broader impacts of the proposal include training the next generation of science teachers to provide instruction to K-12 students of rural Alaska, engaging students (high school, undergraduate, and graduate) and postdoctoral trainees from traditionally underrepresented backgrounds in collaborative research, and disseminating research findings to scientists and the general public. Sleep is essential for most organisms, although its precise function is enigmatic. Chronic sleep loss is well known to have detrimental effects on human health and performance. However, other species display a diversity of sleep patterns that challenge the assumption that reduced sleep is costly for all vertebrates. This proposal takes advantage of state-of-the-art miniaturized transmitters to assess sleep architecture in free-ranging songbirds. Arctic-breeding passerines exhibit extended wakefulness during migration and are active 20 hours/day on their breeding grounds where continuous daylight prevails. The project aims to investigate the sleep/wake cycles of two species of songbirds with different life-history strategies that breed in the high Arctic (Barrow, Alaska, 71° N). It is hypothesized that both natural and sexual selection play a role in determining their sleep patterns. Next, daily sleep will be experimentally increased or decreased to assess life-history tradeoffs with fecundity and/or survivorship. Lastly, the hypothesis will be tested whether arctic-breeding songbirds are more resilient to metabolic, cognitive, hormonal, and immunological costs of sleep loss compared with temperate-breeding birds in captivity. Broader impacts include a Future Teachers of Science program that fosters training of science teachers to develop teaching modules for K-12 students of rural Alaska and a cross-cultural research program for high school students of Alaska and Kentucky to assist with field research. Results from the research will contribute to our understanding of how arctic-dwelling species, including humans, cope with continuous periods of arctic light.