Diurnal lizards, tortoises, terrapins (known as turtles in America)
and crocodilians require access to UVB light to absorb calcium from their food.
Under natural conditions reptiles would get UVB from sunlight. In captivity we
have to provide UVB light by artificial means, this is done with special
light bulbs which give of UVB light. Note that normal basking lamps do not give
off UVB. You can give your reptile as much calcium supplement as you
like, but without a source of UVB your reptile will not be able to absorb the