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Full-Text Articles in Physiology
Polar Bear Behavior: Morphologic And Physiologic Adaptations, John P. Whiteman
Polar Bear Behavior: Morphologic And Physiologic Adaptations, John P. Whiteman
Biological Sciences Faculty Publications
Polar bears possess morphologic and physiologic characteristics that reflect their terrestrial lineage as members of the bear family (Ursidae) as well as adaptations to the Arctic marine environment. Among marine mammals, they are the least adapted for aquatic life. They exhibit substantial seasonality in body mass, body condition, and many physiological functions, reflecting the annual cycle of both their Arctic sea ice habitat and the availability of their main prey, ringed seals. This hypercarnivorous diet has likely influenced the polar bear’s craniodental morphology and nutritional physiology. Similar to other marine mammal predators, polar bears exhibit a relatively high resting metabolic …
Food Availability Modulates Temperature-Dependent Effects On Growth, Reproduction, And Survival In Daphnia Magna, Gustavo S. Betini, Xueqi Wang, Tal Avgar, Matthew M. Guzzo, John M. Fryxell
Food Availability Modulates Temperature-Dependent Effects On Growth, Reproduction, And Survival In Daphnia Magna, Gustavo S. Betini, Xueqi Wang, Tal Avgar, Matthew M. Guzzo, John M. Fryxell
Wildland Resources Faculty Publications
Reduced body size and accelerated life cycle due to warming are considered major ecological responses to climate change with fitness costs at the individual level. Surprisingly, we know little about how relevant ecological factors can alter these life history trade‐offs and their consequences for individual fitness. Here, we show that food modulates temperature‐dependent effects on body size in the water flea Daphnia magna and interacts with temperature to affect life history parameters. We exposed 412 individuals to a factorial manipulation of food abundance and temperature, tracked each reproductive event, and took daily measurements of body size from each individual. High …
Temperature Effects On Growth And Stress Physiology Of Brook Trout: Implications For Climate Change Impacts On An Iconic Cold-Water Fish, Joseph G. Chadwick Jr
Temperature Effects On Growth And Stress Physiology Of Brook Trout: Implications For Climate Change Impacts On An Iconic Cold-Water Fish, Joseph G. Chadwick Jr
Masters Theses 1911 - February 2014
Despite the threat of climate change, the physiological mechanisms by which temperature drives the distribution of species are unclear. Here we used chronic temperature exposures to determine that the upper limit for positive growth in the eastern brook trout (Salvelinus fontinalis) is 23.4 °C. Additionally, brook trout exposed to daily temperature oscillations of 8 °C, around a mean of 21 °C, exhibited growth rates that were 43 and 35% lower by length and weight respectively, than in constant 21 °C controls. Limitations in growth were associated with increases in indicators of the physiological stress response. Individuals exposed to …