TAMPA, Fla. (Nov. 20, 2013) - When invasive species move into new areas, they often lose their natural enemies, including the microbes that make them sick. But new research from evolutionary biologists at the University of South Florida has found that adjustments in the immune system may help house sparrows, one of the world's most common bird species, thrive in new areas.
In research published this week in Proceedings of the Royal Society B, Biological Sciences, Associate Professor Lynn Martin and Assistant Professor Aaron Schrey from Armstrong Atlantic State University found that on the molecular level, the immune systems of house sparrows at the edge of the species' range in Kenya were more attuned to finding dangerous parasites than birds from older sites in the same country. These differences may help keep invading birds from becoming sick in new areas where pathogens are more likely novel.
"A major function of the immune system is distinguishing self from non-self, and immune cells do this with special receptors that look for molecules made by microbes that animal cells don't make," Martin said.
"In the range edge populations, sparrows' immune cells expressed a lot more of the surveillance molecule for microbe components than in old sites. So, perhaps their immune systems are more attuned to finding particularly harmful parasites in new regions where parasites are more likely novel."
USF graduate student Courtney Coon and recent Ph.D. graduate Andrea Liebl, now post-doctoral researcher with the University of Exeter-Cornwall, were part of the research team.
Martin's lab has focused much of their efforts understanding how invasive species spread across the globe. Their main study species, also known as the English sparrow, spread rapidly across North and South America as well as Australia and now Africa and Southeast Asia since they were introduced from Western Europe more than 150 years ago.
Aggressive and often crow
|Contact: Vickie Chachere|
University of South Florida (USF Health)