A preference for big-city living or small-town life may depend in part on inheritance, at least for cliff swallows.
Five-day-old nestlings that researchers switched to a colony of a different size from their original home grew up to nest in colonies like those of their birth parents, not their foster parents, report Charles R. Brown and Mary Bomberger Brown of the University of Tulsa in Oklahoma. They don't rule out effects of very early development but suggest inheritance as a strong possible explanation.
"This study is the first on any taxa, to our knowledge, that has measured heritability of group-size preference," they say in the Dec. 19 Proceedings of the National Academy of Sciences.
After 19 years of studying cliff swallows near Ogallala, Neb., Charles Brown recognizes the tradeoffs of living