They, for example bats, use a high frequency sound to detect small objects like insects. Color vision is less well developed in mammals than in reptiles and birds. Many mammals have no color perception. V. Excretion and Osmoregulation Excretion of urine in mammals is a major source of water loss. It takes considerable water to wash urea from the body.
Some mammals are well adapted to living in very dry environments.
The Kangaroo rat is a good example. This is a very general topic. Read about these complex behaviors in this short review in your text on page 336. It is an area defended from other members of the same species so there will be a secure food supply and shelter for the owners of the territory. Many mammals mark their territories, especially those of the Deer Family, the Dog Family and the Cat Family.