Study Explains How Costly Traits Evolve

FLORA AND FAUNA

The hitchhiker's guide to altruism

by Staff Writers
Oxford UK (SPX) Jan 22, 2007
Darwin explained how beneficial traits accumulate in natural populations, but how do costly traits evolve? In the past, two theories have addressed this problem. The theory of hitchhiking suggests that genes that confer a cost to their bearer can become common in natural populations when they "hitch a ride" with fitter genes that are being favored by natural selection. Conversely, the theory of kin selection suggests that costly traits can be favored if they lead to benefits for relatives of the bearer, who also carry the gene.

"Animal traits are not always independent. For example, people with blond hair are more likely to have blue eyes," explains Andy Gardner (Oxford University). "This is a nuisance for natural selection, which could not, for instance, favor blond hair without also indirectly favoring blue eyes, and this is the idea of genetic hitchhiking."

Kin selection is similar, but here the genetic associations are between different individuals: "If I have a gene that makes me more altruistic, then I can also expect my relatives to carry it. So while the immediate effect of the gene is costly for me, I would benefit by receiving altruism from my relatives, and so the gene is ultimately favored," Gardner explains.

New research carried out at the University of Edinburgh and Queen's University, Canada shows that both processes are governed by the same equations. This reveals that kin selection can be seen as a special form of genetic hitchhiking, explain Gardner and his coauthors Stuart West and Nick Barton (University of Edinburgh) in the February issue of The American Naturalist.

The researchers built on a general framework for modeling hitchhiking first proposed by Barton and colleagues, showing how it can be used to describe social evolution and recovering the classical results of kin selection theory. This insight raises the possibility of using the tools of hitchhiking theory to explore social problems that have so far been too complicated to analyze using traditional kin selection techniques.

Founded in 1867, The American Naturalist is one of the world's most renowned, peer-reviewed publications in ecology, evolution, and population and integrative biology research. AN emphasizes sophisticated methodologies and innovative theoretical syntheses--all in an effort to advance the knowledge of organic evolution and other broad biological principles. Gardner, Andy, Stuart A. West, and Nicholas H. Barton, "The relation between multilocus population genetics and social evolution theory." The American Naturalist: February 2007.

FLORA AND FAUNA

The Great Preserver

Los Angeles CA (SPX) Jan 22, 2007
The oldest-known animal eggs and embryos, whose first pictures made the cover of Nature in 1998, were so small they looked like bugs - which, it now appears, they may have been. A new study in the journal Nature presents evidence for reinterpreting the 600 million-year-old fossils from the Precambrian era as giant bacteria. The finding may change our understanding of Earth's fossil record.

DISASTER MANAGEMENT Lockheed Martin Wins Major CDC Contract To Support Emergency Response Preparedness USJFCOM Hosts First-Responder Focused Modeling And Simulation Demonstration Event Rural America Better Prepared For Disaster Management Many Environments Resilient In The Face Of Hurricanes	CLIMATE SCIENCE Top US Firms To Urge Congress To Fight Global Warming Deep In Arctic Mud And Geologists Find Strong Evidence Of Climate Change Evangelicals Embrace Climate Change Science To Save The World Climate Change Could Amplify Drought In East Indian Ocean And Australasia
EARTH OBSERVATION Chairman Reacts to National Academies' Earth Science and Applications Assessment Egypt Plans First Remote Sensing Satellite Japanese Government Initiates Space-Borne Hyperspectral Payload Program US Climate Satellites Imperiled By Low Federal Funding Say EO Scientists	ENERGY TECH Big Oil Digs In Heels As Congress Moves On Tax Breaks Canada's New Government Launches EcoEnergy Technology Initiative New Fuel Cell Design Adds Better Control While Reducing Complexity Survey Shows Strong Support For Offshore Wind Power
EPIDEMICS Study Uncovers A Lethal Secret Of 1918 Influenza Virus Scientists Reveal A Virus' Secret Weapon World's Response To Children With Aids 'Tragically Insufficient' UN Body Says EU Ban On Wild Bird Imports Won't Help Stop Bird Flu	FLORA AND FAUNA The Great Preserver Study Explains How Costly Traits Evolve Shotgun Sequencing Slime Big Vegetarian Mammals Play Critical Role In Maintaining Healthy Ecosystems
FROTH AND BUBBLE Flights To Avoid Indonesian Mud Volcano Postponed Lead With A Poisonous Electron Shield Oil Slick Fouls Hundreds Of Birds Off Norway Unlocking Pollutants' Effects	ABOUT US Next Up In The Battle Against Cancer Putting A Face On The Earliest Modern Europeans 40,000-Year-Old Skull Shows Both Modern Human And Neanderthal Traits Hofmeyr-Skull Supports The "Out of Africa"-Theory

The content herein, unless otherwise known to be public domain, are Copyright 1995-2006 - SpaceDaily.AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA PortalReports are copyright European Space Agency. All NASA sourced material is public domain. Additionalcopyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement