On Color Vision

Written by: Emel Kцkrek

Date: 17.10.05

Color Vision

The researchers1 had another clue in the process of understanding evolution by examining a group of closely-related fish species which, as it is proven, might respond to their particular environments by interpreting the visual world slightly differently. The result they came up with is "using photoreceptors that are attuned to particular wavelights of light" the vision of these species is shaped by the evolution. The examined group is Cichlid fish species of the East African Rift Lakes. According to the report, it is estimated that Cichlid fish, migrating from Lake Tanganyika, have given rise to lots of new Cichlid species in the last 100,000 years that is a relatively short period of evolutionary time. The reason why these species are chosen is given in the report: "Thanks to the relatively recent colonization by these fish of different ecological niches, as well as the prominent role of nuptual coloring in the mating preferences of these species, the cichlids offer a unique opportunity to study how color vision can undergo change in rapidly evolving species."2 By the new physiological and molecular genetic analyses, the fish create different color visions by using different subsets of distinct visual pigments. They express the pigments in a unique way though there are many posibilities to all of them. So the result is the difference in how the visual world is sensed. The report includes the details of that visual pigments and ends with "Evolutionary comparison of pigment genes suggests that other groups of fish may use a similar strategy for shaping their color vision."

The selective attitude of Cichlid fish species can be explained by the evoulutionary comparison of pigment genes. If we go further, it can be said that their specialization in color vision might affect the other species in that environment as well as their own speciation. In the aspect of the predation relationship, even co-evolution might be mentioned.3 If a strategy is applied to this fish species, it may