Life in the cold can be difficult for animals. As the body chills, organs including the brain and muscles slow down.
The body temperature of animals such as reptiles and amphibians mostly depends on the temperature of their environment—but mammals can increase their metabolism, using more energy to warm their body. This allows them to live in colder areas and stay active when temperatures drop at night or during winter months.
Although scientists know mammals can increase their metabolism in the cold, it has not been clear which organs or tissues are using this extra energy to generate more heat. Staying warm is especially challenging for small, aquatic mammals like sea otters, so we wanted to know how they have adapted to survive the cold.
We assembled a research team with expertise in both human and marine mammal metabolism, including Heidi Pearson of the University of Alaska Southeast and Mike ...
