Featured Research

from universities, journals, and other organizations

Multiple Genes Permit Closely Related Fish Species To Mix And Match Their Color Vision

Date:
October 16, 2005
Source:
Cell Press
Summary:
Vision is shaped by evolution through environmental pressures and demands, and even closely-related species that might respond to their particular environments by interpreting the visual world slightly differently. By studying a special group of closely-related fish species inhabiting the Great Lakes of Africa, researchers have uncovered clues to understanding how the components of color vision can undergo change over a relatively short period of evolutionary time.

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.
Credit: Justin Marshall

Vision, like other biological attributes, isshaped by evolution through environmental pressures and demands, andeven closely-related species that are in other ways very similar mightrespond to their particular environments by interpreting the visualworld slightly differently, using photoreceptors that are attuned toparticular wavelengths of light. By studying a special group ofclosely-related fish species inhabiting the Great Lakes of Africa,researchers have uncovered clues to understanding how the components ofcolor vision can undergo change over a relatively short period ofevolutionary time.

Related Articles


The work is reported by James K. Bowmaker of University CollegeLondon, Karen L. Carleton of the University of New Hampshire, and theircolleagues.

Cichlid fish of the East African Rift Lakes are renowned fortheir diversity: Owing to migrations of ancestor species out of LakeTanganyika and into other lakes, such as Lake Malawi, it has beenestimated that hundreds of new cichlid species have arisen in theselakes in the last 100,000 years. Thanks to the relatively recentcolonization by these fish of different ecological niches, as well asthe prominent role of nuptual coloring in the mating preferences ofthese species, the cichlids offer a unique opportunity to study howcolor vision can undergo change in rapidly evolving species. Forexample, because color plays a significant role in mate choice,differences in color vision could greatly influence and even drivecichlid speciation.

In the new work, the researchers performed physiological andmolecular genetic analyses of color vision in cichlid fish from LakeMalawi and demonstrated that differences in color vision betweenclosely related species arise from individual species' using differentsubsets of distinct visual pigments. The scientists showed thatalthough an unexpectedly large group of these visual pigments areavailable to all the species, each expresses the pigments selectively,and in an individual way, resulting in differences in how the visualworld is sensed.

The researchers identified a total of seven "cone"(color-sensing) visual pigments underlying color vision in thesecichlids. They have measured the sensitivities of the cones todifferent wavelengths of light and isolated the seven genes that giverise to the pigment proteins. The seven cone types have maximumsensitivities ranging from the red end of the spectrum right through tothe ultraviolet--light outside the range of human sensitivity. Theresearchers showed that in order to tune its color vision, each cichlidspecies primarily expresses three of the seven cone pigment genesencoded by their genomes.

It is not clear why such closely related cichlid species haveevolved such different visual sensitivities, but the sensitivities mostlikely relate to such selective forces as foraging specializations andsubtle differences in the underwater light environment. Evolutionarycomparison of pigment genes suggests that other groups of fish may usea similar strategy for shaping their color vision.

###

The researchers included Juliet W.L. Parry, Aba Carboo, David M.Hunt, and James K. Bowmaker of University College in London, UnitedKingdom; Karen L. Carleton and Tyrone Spady of the University of NewHampshire, Durham, New Hampshire. This work was supported by theLeverhulme Trust and by the National Science Foundation.

Parry et al.: "Mix and match colour vision: tuning spectralsensitivity by differential opsin gene expression in Lake Malawicichlids." Publishing in Current Biology, Vol. 15, pages 1734-1739,October 11, 2005. DOI 10.1016/j.cub.2005.08.010 www.current-biology.com


Story Source:

The above story is based on materials provided by Cell Press. Note: Materials may be edited for content and length.


Cite This Page:

Cell Press. "Multiple Genes Permit Closely Related Fish Species To Mix And Match Their Color Vision." ScienceDaily. ScienceDaily, 16 October 2005. <www.sciencedaily.com/releases/2005/10/051011072648.htm>.
Cell Press. (2005, October 16). Multiple Genes Permit Closely Related Fish Species To Mix And Match Their Color Vision. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2005/10/051011072648.htm
Cell Press. "Multiple Genes Permit Closely Related Fish Species To Mix And Match Their Color Vision." ScienceDaily. www.sciencedaily.com/releases/2005/10/051011072648.htm (accessed October 24, 2014).

Share This



More Plants & Animals News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Black Bear Cub Goes Sunday Shopping

Black Bear Cub Goes Sunday Shopping

Reuters - Light News Video Online (Oct. 23, 2014) Price check on honey? Bear cub startles Oregon drugstore shoppers. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins