Featured Research

from universities, journals, and other organizations

Sex is not about promoting genetic variation, researchers argue

Date:
July 7, 2011
Source:
Wayne State University - Office of the Vice President for Research
Summary:
Biology textbooks maintain that the main function of sex is to promote genetic diversity. But in a new article, two researchers say that's not the case. They propose that although diversity may result from a combination of genes, the primary function of sex is not about promoting diversity. Rather, it's about keeping the genome context -- an organism's complete collection of genes arranged by chromosome composition and topology -- as unchanged as possible, thereby maintaining a species' identity.

Biology textbooks maintain that the main function of sex is to promote genetic diversity. But Henry Heng, Ph.D., associate professor in WSU's Center for Molecular Medicine and Genetics, says that's not the case.

Related Articles


Heng and fellow researcher Root Gorelick, Ph.D., associate professor at Carleton University in Canada, propose that although diversity may result from a combination of genes, the primary function of sex is not about promoting diversity. Rather, it's about keeping the genome context -- an organism's complete collection of genes arranged by chromosome composition and topology -- as unchanged as possible, thereby maintaining a species' identity. This surprising analysis has been published as a cover article in a recent issue of the journal Evolution.

"If sex was merely for increasing genetic diversity, it would not have evolved in the first place," said Heng. This is because asexual reproduction -- in which only one parent is needed to procreate -- leads to higher rates of genetic diversity than sex.

For nearly 130 years, traditional perceptions hold that asexual reproduction generates clone-like offspring and sexual reproduction leads to more diverse offspring. "In reality, however, the relationship is quite the opposite," said Heng.

And not only does asexual reproduction lead to higher rates of genetic diversity, it also is two times more efficient than sexual reproduction.

In fact, two billion years ago in Earth's biosphere, life relied exclusively on asexual reproduction, and every organism was capable of bearing young without costly competition to mate. With asexual species' faster and more efficient mode of reproduction, the origin and maintenance of sex -- not exactly the fittest means of reproduction -- puzzles scientists, who for decades have been asking, Why has sex evolved and survived?

Although many scientists have offered answers to this question, most have focused on the benefit of mixing or purifying genes. But by taking the genome theory into account, Heng's findings may have dethroned the queen of problems in evolutionary biology.

According to Heng, the hidden advantage sex has over asexual reproduction is that it constrains macroevolution -- evolution at the genome level -- to allow a species' identity to survive. In other words, it prevents "Species A" from morphing into "Species B." Meanwhile, it also allows for microevolution -- evolution at the gene level -- to allow members of the species to adapt to the environment.

Considering their observations and those of paleontologists, population geneticists and ecologists cited in the article, Heng and Gorelick argue that new research should focus on the genome, not just the individual genes, because the genome serves as both the genetic information unit and selection package for evolution.


Story Source:

The above story is based on materials provided by Wayne State University - Office of the Vice President for Research. Note: Materials may be edited for content and length.


Journal Reference:

  1. Root Gorelick, Henry H. Q. Heng. Sex Reduces Genetic Variation: A Multidisciplinary Review. Evolution, 2011; 65 (4): 1088 DOI: 10.1111/j.1558-5646.2010.01173.x

Cite This Page:

Wayne State University - Office of the Vice President for Research. "Sex is not about promoting genetic variation, researchers argue." ScienceDaily. ScienceDaily, 7 July 2011. <www.sciencedaily.com/releases/2011/07/110707161037.htm>.
Wayne State University - Office of the Vice President for Research. (2011, July 7). Sex is not about promoting genetic variation, researchers argue. ScienceDaily. Retrieved January 25, 2015 from www.sciencedaily.com/releases/2011/07/110707161037.htm
Wayne State University - Office of the Vice President for Research. "Sex is not about promoting genetic variation, researchers argue." ScienceDaily. www.sciencedaily.com/releases/2011/07/110707161037.htm (accessed January 25, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Sunday, January 25, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Florida Might Legalize Black Bear Hunting

Florida Might Legalize Black Bear Hunting

Newsy (Jan. 24, 2015) A string of black bear attacks has Florida officials considering lifting the ban on hunting the animals to control their population. Video provided by Newsy
Powered by NewsLook.com
Ebola Killing Large Portion Of Ape Population

Ebola Killing Large Portion Of Ape Population

Newsy (Jan. 23, 2015) Experts estimate Ebola has wiped out one-third of the world&apos;s gorillas and chimpanzees. Video provided by Newsy
Powered by NewsLook.com
Controversy Shrouds Captive Killer Whale in Miami

Controversy Shrouds Captive Killer Whale in Miami

Reuters - Light News Video Online (Jan. 23, 2015) Activists hope the National Oceanic and Atmospheric Agency (NOAA) will label killer whales endangered, allowing lawyers to sue a Miami aquarium to release an orca into the wild after 44 years. Jillian Kitchener reports. Video provided by Reuters
Powered by NewsLook.com
‘Healthy’ Foods That Surprisingly Pack on Pounds

‘Healthy’ Foods That Surprisingly Pack on Pounds

Buzz60 (Jan. 23, 2015) Some &apos;healthy&apos; foods are actually fattening. Fitness and nutrition expert John Basedow (@JohnBasedow) shines a light on the sneaky foods like nuts, seeds, granola, trail mix, avocados, guacamole, olive oil, peanut butter, fruit juices and salads that are good for you...but not so much for your waistline. Video provided by Buzz60
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