How much Ultraviolet light receive reptiles in nature?
Ultraviolet radiation is expressed in microwatt per square centimeter (mW/cm2) and varies tremendously from the poles (low) towards the equator (high). The amount of UVB radiation received on the equator on a clear day at noon is around 270 mW/cm2. However, this high amount of radiation decreases as the day passes, in the same way that it had increased since sunrise and taking into consideration that not all days are clear. In the wild, basking activities of most reptiles are limited to the early morning and later afternoon. The rest of the day is spent in the shade, in burrows, crevices or other shaded places, or at various places in leafy bushes, shrubs or trees. In tropical forests, home to many types of reptiles and amphibians, only a little direct sun penetrates the forest canopy and underlying layers to reach the ground.
