Which adaptation helps animals survive extreme temperatures?

Physiological insulation is a critical adaptation for animals living in extreme temperatures, particularly in cold environments. This adaptation refers to the mechanisms an animal employs to minimize heat loss or to maintain body temperature within a suitable range. For instance, many mammals, such as polar bears or seals, have thick layers of fat (blubber) and dense fur that provide insulation against the cold. This layer of insulation minimizes heat loss from the body, allowing these animals to survive and thrive in frigid temperatures.

In warm environments, certain adaptations like reduced fur density or the presence of specialized sweat glands help to dissipate heat, ensuring that the body temperature remains stable despite external heat. This physiological insulation mechanism is vital for maintaining homeostasis, which is essential for survival in extreme temperature conditions.

Other adaptations mentioned do not specifically address the challenges associated with extreme temperatures in the same direct manner. For example, increased lung capacity primarily benefits aerobic metabolism and oxygenation rather than temperature regulation, while color change for camouflage serves a different purpose related to predation and not thermoregulation. Enhanced eyesight could improve foraging and predator detection but is not related to temperature adaptation. Therefore, physiological insulation stands out as the most relevant adaptation for surviving extreme temperatures.