Why don elephants have sweat glands?
It’s a matter of luck whether an animal will evolve a certain feature. If they don’t, and the feature is vital for survival, then the result could be extinction. At the end of the last ice age, a lot of large mammals became extinct. If they had sweat glands, they could have persisted to the present because they probably died of heat strokes. Their large body meant that they have a very low surface area to volume ratio, which make its hard for them to get rid of excess body heat in warm or hot weather, especially after exercising. Data from the polar ice cores showed that ambient temperatures spiked upward abruptly at the end of the last ice age, giving the large mammals no time to adapt to the temperature changes.
