The bat has slowed down his metabolism during the cold, dark winters. It doesn't have to forage for food.
hibernation
Earthworms will burrow underground when the sun is out in full force. If they don't they will dry up and die.
estivation
These sprouts will grow towards the sun. This aids in photosynthesis.
phototropism
Birds so this because of weather or to hatch their young or to find food.
migration
This plant isn't dead. It has stopped growing until the weather gets warmer and the daylight hours increase.
dormancy
