Light of cellular water are raised in temperature by the infrared radiation. EMR in this range causes molecular vibration and heating effects, which is how these animals detect it. Above the range of visible light, ultraviolet light becomes invisible to humans, mostly because it is absorbed by the cornea below 360 nm and the internal lens below 400 nm. Furthermore, the rods and cones located in the retina of the human eye cannot detect the very short (below 360 nm) ultraviolet wavelengths and are in fact damaged by ultraviolet. Many animals with eyes that do not require lenses (such as insects
Ultraviolet communication in butterflies UV reflecting scales are composed of raised longitudinal ridges and perpendicular cross ribs that connect the parallel running ridges, forming a grid. The ridges possess lamellae that run on top of and parallel to the ridges and microribs on its sides. The partial overlap of lamellae structures causes thin layer interference resulting in the reflection of light with a wavelength within the ultraviolet spectrum. The other ultraviolet signal in butterflies, absorbance, was determined to be governed by pigments called pterins. In wings containing this pigment, the wings are unable to reflect ultraviolet light as well as without the pigment because