Bear
Bears demonstrate a remarkable form of torpor that allows survival through extended periods without food while avoiding the muscle loss that typically accompanies starvation.
Bears demonstrate a remarkable form of torpor that allows survival through extended periods without food while avoiding the muscle loss that typically accompanies starvation. During their 7-month torpor, bears don't eat, drink, urinate, or defecate - surviving entirely on fat reserves while their metabolism drops by about 75%.
What makes bears particularly instructive is their ability to avoid Phase 3 protein catabolism. They've evolved mechanisms to recycle urea (a waste product of protein breakdown) back into amino acids, preventing muscle loss. When they emerge in spring, they're thin but functional - demonstrating that strategic metabolic reduction can enable survival without permanent damage.
Notable Traits of Bear
- Can torpor for up to 7 months
- Metabolism drops ~75% during torpor
- Body temperature drops only 5-7°C
- Recycles urea to prevent muscle loss
- No eating, drinking, urinating, or defecating during torpor