The common garter snake (thamnophis sirtalis) is found throughout north america. in the south, it is active year round. in the north, it is active during the warmer months but hibernates during the winter. it is commonly found basking on warm rocks during cool mornings. this lifestyle indicates that the snake is

The common garter snake (Thamnophis sirtalis) is found throughout North America. In the South, it is active year round. In the North, it is active during the warmer months but hibernates during the winter. It is commonly found basking on warm rocks during cool mornings. This lifestyle indicates that the snake is probably heterothermic.

Explanation:

Being heterothermic, like all reptiles, garter snakes bask in the sun to regulate their body temperature. During brumation (the reptile equivalent of hibernation), garter snakes typically commonly den together. Sometimes there will be as many as 100 snakes in one cave. A large, communal or group site is called a hibernaculum they occupy is called hibernacula. These snakes will migrate large distances to brumate.

Snakes do not actually hibernate, rather they become less active during cold weather. It is called "brumation."  Brumation is an extreme slowing down of their metabolism. Snakes are awake, but just very lethargic so you don't see them moving around.

During fall, snakes go back to the previous year’s den. When a sudden cold catches them before they get there, they may die if not fortunate enough to  find a suitable secondary den. They usually do not stay long at the den entrance, but hurry in for the long winter sleep.

Cold-blooded animals like snakes, fish, frogs, and turtles need to spend the winter inactive, or dormant,  because they have no way to keep warm. Snakes will crawl into any area free from frost such as caves, hollow logs, holes under trees and stumps, under wood piles, in other animal's burrows, and occasionally in a person's basement.

the genotypes would be 50% bb and 50% bb

the phenotypes would be 50% brown and 50% white. hope this : )