Amild environment begins to experience a gradual decrease in temperature resulting in much colder winters than previous years. which variation would most likely be selected for in an organism that lives in this environment?

This sort of environment would result in animals with longer and denser coats of fur. However, since colder weather usually occurs over winter, some animals may develop an adaptation of hibernating over winter. In snowy environments, some animals may develop feet with a larger surface area to allow walking on snow. Some animals in a snowy environment may turn white to blend in with the landscape. Some animals may build up layers of fat during the summer so that they are more insulated during winter. 

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