A tree frog is any frog that spends a major portion of its lifespan in trees, known as an arboreal state. They do not normally descend to the ground, except to mate and spawn, though some build foam nests on leaves and rarely leave the trees at all as adults. Tree frogs are usually tiny, as their weight has to be carried by the branches and twigs in their habitats.
They can swim and stay in water for long periods of time, though, but this isn't their usual habitat. Tree frogs mainly go to the water in order to create mating calls, to mate or to accumulate water and absorb it through their pores.
Frogs are ectotherms which means that their body temperature is dependent on external environmental conditions. Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. Therefore, frogs cannot effectively regulate their temperature internally; instead they maintain their preferred temperature via behavior. If a frog needs to heat up, it will bask in the sun or otherwise draw heat from the environment. If it is too hot, it can enter the water, retreat to a shelter, adopt a lighter color or adjust his evaporative cooling rate.
'When retreating into the water, it being much cooler than the air is, the frogs will not only cool down through conduction, but will also rehydrate, which allows them to use evaporative cooling. 'A simple solution for an overheated frog is to move out of sunlight and into a cooler, sheltered location. Green tree frogs may hide under tree bark or inside a tree hollow to escape high temperatures.
The color of an ectothermic animal can be important to the creature's thermoregulation; dark-colored animals tend to warm up quickly, while light-colored animals cool off more quickly. Some frog species are able to change their color or pattern, and though this undoubtedly allows them to better hide from predators, scientists suspect that most species also use their color-changing abilities to thermoregulate, e.g such as the Pacific tree and the grey White’s tree frogs.
When temperatures are high, water begins to evaporate from the skin of frogs, which produces a cooling effect. As long as they have access to water, frogs can usually adapt to reasonably high temperatures; this is one of the reasons that moisture and humidity are vital to a frog’s survival.