August 5, 2009

Minute DNA change could lead to evolution

One tiny change in DNA could lead to the evolution of a new species, an English researcher reported.

A team lead by a University of Cambridge scientist explored this possibility when they studied two closely related flycatcher populations in the Solomon Islands, reporting their results in the American Naturalists.

The scientists said they studied two sub-species with the same body shape, but different colored bellies and distinct songs. Birds from these sub-species could mate, but sub-species' differences prevented them from recognizing each other as potential sexual partners.

Researchers said the ability to mate but the lack of recognition indicated the beginning of the evolution of new species. Other flycatchers in the Solomon Islands, east of Papua New Guinea, also differed in plumage color, but the genetic basis is not always as clear as a single DNA mutation, researchers said.

Rebecca Kilner of Britain's University of Cambridge said the study indicates how a single gene can cause color change in birds, affecting the selection of potential sexual partners.

Research indicated the DNA change could lead to reproductive isolation and eventually speciation, she said, but in ways that are more complex than previously appreciated.