Question

Which of the following is not an important adaptation of animals to cold climate
A. A thin layer of body fat
B. Aestivation
C. Increased tendency to shiver
D. Reduced surface area to volume ratio

Answer 1

Hint: A variety of adaptation techniques are used by animals living in extreme cold habitats to withstand the low temperature. The main technique is by an insulation layer to keep the cold away, and also other ways to keep the body temperature at check.

Complete answer: The animals inhabiting cold regions possess a thick layer of body fat than the animals living in warmer areas. The layer of fat helps in creating an insulation layer so that not much heat is lost from their body. The heat is retained and the temperature remains constant. Both land and water animals possess this layer of fat. The layer present in certain animals such as seals is known as blubber. Thus the animals in cold regions possess a thick layer of body fat.
Considering the other given options:
-Aestivation can be described as a state of dormancy exhibited by animals inhabiting cold regions. It is a process similar to the hibernation process, the major difference between them being aestivation happens in winter whereas hibernation occurs in the summer season. During aestivation, the animals take a state of inactivity with minimized metabolism. Thereby conserving energy to a large extent.
-The process of shivering helps in increasing body temperature. The process is regulated by the nervous system. This process also helps in maintaining normal body temperature.
-Animals living in cold climate regions are adapted such that, they have a reduced surface area to volume ratio. This adaptation technique helps in reducing the area by which these animals dissipate heat to the surroundings. Thereby their bodies get to retain more heat. This kind of technique can be explained based on Allen’s Rule, which states that “animals adapted to cold climates have shorter limbs and bodily appendages, compared to animals of warm climates.
Thus, from the given set of options, the one which is not seen in winter animals or is not an adaptation of animals in winter is the presence of a thin layer of body fat, which is option A. Since animals living in winter regions possess a thick layer of body fat.
Hence, the correct answer is Option A

Note: Similar to adaptive techniques in winter, animals surviving in extreme summers also adapt to reduce body temperature. The animals possess a large body surface area, conserve water, and very less amount of body fur, to maximize the amount of heat loss.