The work is reported by James K. Bowmaker of University College London, Karen L. Carleton of the University of New Hampshire, and their colleagues.
Cichlid fish of the East African Rift Lakes are renowned for their diversity: Owing to migrations of ancestor species out of Lake Tanganyika and into other lakes, such as Lake Malawi, it has been estimated that hundreds of new cichlid species have arisen in these lakes in the last 100,000 years. 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. For example, because color plays a significant role in mate choice, differences in color vision could greatly influence and even drive cichlid speciation.
In the new work, the researchers performed physiological and molecular genetic analyses of color vision in cichlid fish from Lake Malawi and demonstrated that differences in color vision between closely related species arise from individual species' using different subsets of distinct visual pigments. The scientists showed that although an unexpectedly large group of these visual pigments are available to all the species, each expresses the pigments selectively,
Contact: Heidi Hardman