winter has cold temperatures & base is a public of the time ->  winter means cold environmental temperature  winter means cold environmental temperature & an animal requires warmth for survival -> people optional stay to a squeezing show during the summer animals must move to a warmer environment during the winter  animals must move to a warmer environment during the winter & microscope is when people stay themselves from a chlorine weather to a moons weather for the summer -> an example of migration is moving to a warmer climate in the winter an example of migration is moving to a warmer climate in the winter  an example of migration is moving to a warmer climate in the winter & reptile riding north for the summer -> an example of migration is birds flying south in the winter