The primary strategy for dealing with high desert temperatures is avoidance- many mammals simply avoid the high daytime temperatures by being nocturnal or crepuscular ( dusk-or-dawn-active). A bobcat, for instance is typically most active at dusk and dawn, a javelina is never active during the day in summer, but it may be in winter. Even day-active birds are most active at cooler dawn. Many mammals, such as ringtails or kangaroo rats are never active during the day.
Some mammals create their own microclimate. A white- throated wood rat(or pack rat) build a den made of desert litter-cholla joints, prickly pear pads, sticks and stones-within a clump of prickly pear cactus. It looks a little like a trash heap and may be three feet high and eight feet across. At the bottom of the pile is a series of tunnels leading to a nest of soft plant fibers. The pack rat spends its day in the soft nest, somewhat insulated from exterior air temperature that may be 110F or 43C, with a ground surface temperature of 160F or 71C.
Squirrels may often be observed pressing their bellies, with legs spread, against the cool soil or even tile of suburban patios in shady spots, allowing it is presumed their body heat to be conducted to the cooler earth in their burrows in similar fashion when they retreat to them in on hot days.
Kangaroos -There is a network of blood vessels in their forearms that is capable of cooling down their whole body. When they lick them until they are soaking wet, their whole body temperature is lowered as the saliva evaporates.