By DAVID WILLIAMSON
UNC-CH News Services
CHAPEL HILL -- Spying on birds with binoculars while tape recording their sounds on a cattle ranch south of Caracas, Venezuela, a young University of North Carolina at Chapel Hill biologist has discovered that certain male songbirds learn calls only from their fathers. Conversely, females of the species -- stripe-backed wrens -- learn calls exclusively from their mothers.
Jordan Price says the discovery is unique because it shows how sounds birds produce can reflect both sex and kinship. He described the "his and her" vocal instruction as "a striking example of sex-specific learning."
"Male stripe-backed wrens always produced calls acoustically identical to their fathers'," said Price, who did the research for his doctorate. "Female stripe-backed wrens from the same line matched their mothers' calls exactly."
Calls of males and females in the same family never matched, he said.
"Twice I found two males living more than a kilometer apart that had nearly identical calls. By looking at records from the 1970s, I discovered that they had the same paternal great-grandfather."
In five years of field work, Price recorded and analyzed more than 10,000 wren calls in the snake and bug-infested, muddy savannah. His mentor, renowned UNC-CH ornithologist R. Haven Wiley, named the sounds "WAY" calls two decades ago because they brought to mind a nasally congested human asking "Where are you? Where are you?"
Neither males nor females duplicated calls from the opposite sex's repertoire or from any bird but their same-sex parent, he said. A report on the findings appears in the March 22 issue of the Proceedings of the Royal Society of London.
Stripe-backed wrens are termed "cooperative breeders" because they live
in family social groups on commun
Contact: David L. Williamson
University of North Carolina at Chapel Hill