Picky females promote diversity

Researchers suggest that picky females play a critical role in survival and diversity of species, the Science Daily reports.

To date, biodiversity theories have focused on the role of  adaptions in the environment, where the species that are best equipped to cope with a habitat would survive and others would gradually go extinct.

But the new study presents the first theoretical model that demonstrates that selective mating alone can promote the long-term coexistence of species. An example is how frogs, crickets, grasshoppers and fish share the same ecological adaptions and often interbreed.

The study was conducted by scientists from the University of British Columbia and the International Institute for Applied Systems Analysis (IIASA) in Austria, and recently published in the the April 1, 2012, issue in the journal Nature. The new mechanism revealed in their research could explain how a fish such as cichlids, a fish found in Lake Victoria in Africa, can coexist in high diversity in the same habitat.

"The focus on ecological adaptation has failed to explain much of the biodiversity we see right before our eyes," Leithen M'Gonigle said, the lead author and postdoctoral fellow at the University of Californian at Berkley.

Their model suggests that species can coexist in the same habitat as long as two conditions are met. First, the distribution of resources they use must be inconsistent, so that groups of females with different mate preferences can occupy different resource hotspots.  Second, females must pay a cost for being choosey, either through reduced survival or because of fecundity.

"Resource distribution are never uniform over space, even in seemingly homogeneous habitats like grassland and lakes," Ulf Dieckermann said, a co-author of the study and leader of the Evolution and Ecology Program at IIASA.

When females are picky, they almost always suffer a cost because they spend their energy either to find a preferred mate or to avoid an undesirable one, Sarah Otto said, a  co-author and zoologist at UBC.

"These costs turn out to be crucial for reinforcing species' boundaries," Rupert Mazzucco said, an IIASA scholar and also a co-author of the study. "Because they prevent females with a particular preference from invading areas dominated by males they find unattractive."

The authors suggest that his study open up new understanding and importance of of biological diversity, by overcoming the long-held belief that species can co-exist only if they differ in their ecological adaptions.

This post was originally published on Smartplanet.com