Different genes cause loss of body parts in similar fish

Washington, June 5 (ANI): A new research has shown that different genes can cause loss of body parts in similar fish, by comparing how 2 species of sticklebacks lost pelvises and body armor.

The research, funded by the National Science Foundation (NSF)'s Divisions of Environmental Biology and Integrative Organismal Systems, shows that when two species of stickleback fish evolved and lost their pelvises and body armor, different genes in each species caused the changes.

That surprised researchers, who expected the same genes would control the same changes in both related fish.

Biologists knew that in many cases of evolution, "the same gene has been used over and over again -even in different species - to result in the same anatomy," said Mike Shapiro, first author of the research paper and a biologist at the University of Utah.

"What we are finding now is that different genes can have similar effects," he added.

The findings shed new light on how evolution produces diversity in nature, and on the evolution of limb loss - and not just the loss of the pelvis and leg-like pelvic spines in certain sticklebacks.

"Limb loss is something we see in many other groups-snakes, whales, manatees and some amphibians," Shapiro said. "We can't do genetic studies on those animals. Sticklebacks give us insight into what may be going on in many other animal groups," he added.

The study focused on "convergent evolution," which is when the same trait evolves independently in different species or in separate populations of one species.

A key question has been whether two species use the same gene or different genes when they evolve the same trait.

Scientists know many cases of the same gene causing two different species to evolve the same trait.

The study shows that different genes also can be responsible for evolution of the same traits in two species of stickleback fish.

"Although there is so much diversity in nature, we know very little about the mechanisms that generate that diversity on a genetic level," Shapiro said.

"These fish are increasing diversity within each of their species. It just so happens that both species have found similar solutions to some ecological problem. We found they use different genes to do that, which contradicts earlier research on sticklebacks," he added. (ANI)