What is an example of an adaptation in animals related to their environment?

Thick fur in cold climates is a prime example of an adaptation that enables animals to survive in specific environmental conditions. This type of adaptation is a structural change that directly enhances an animal's ability to cope with cold temperatures. The thick fur acts as insulation, trapping body heat and protecting against the frigid external environment, thus allowing the animal to maintain its body temperature and remain active despite the cold.

The other choices, while they involve adaptations, do not specifically address the direct environmental relationship in the same manner. For instance, bright colors for mating rituals pertain more to reproductive strategies than environmental adaptation. High metabolic rates can help animals generate more energy, but this trait is not specifically tied to survival in a harsh environment. Seasonal migration patterns involve behavioral adaptations rather than structural changes to cope with conditions in a specific habitat. Thus, thick fur stands out as a direct and crucial adaptation for survival in cold climates.