Not all animals, birds, or insects can see in color in any manner that is similar to human color vision. Scientists that study spiders, arachnologists, have found that spiders of the species Habronattus have evolved a unique means of color vision. The spiders are known for their jumping ability and are called jumping spiders. Specialized vision is needed for successful jumping. The discovery was reported by Nathan Morehouse of the University of Pittsburgh and colleagues in the edition of the journal Current Biology.
Habronattus spiders have four pairs of eyes. Each set of eyes provides a different aspect of vision and color vision for the spiders. The most prominent set of eyes can see red, green, and ultraviolet wavelengths of light. The ability to see red is provided by a filter in the eye that converts some of the receptors that are sensitive to seeing green into receptors that recognize red. These spiders are all brightly colored and the development of color vision is considered to be an adaptation that assists mating.
The spiders do not and cannot see color like humans. The field of vision in the Habronattus species is limited by the placement of the four pairs of eyes. The researchers report that the spiders must scan a field line by line in order to acquire enough information to process color vision. Despite the limitations the spiders do have true trichromatic vision that uses three different types of cone cells in the retina. This is one of the few insect species known that has color vision.