The availability of food in the wild will affect the number of winter residents, for example, if there is a poor mast crop in Massachusetts, Blue Jays will migrate ... read more
This change in the amount of light is a signal to animals, plants and, before the light bulb, people, of changing seasons. For some creatures living at high latitudes, it can have a profound effect on their biology, particularly on reproduction, which must be carefully timed. read more