"Tra la la, tweedle dee dee, it gives me a thrill" the song goes, but the scientists who wakened to the mockingbird's trill in Durham, North Carolina, were both puzzled and thrilled by the fact that some birds are plain songsters, while others of the same species are the Pavarottis of the skies. At Current Biology online , they advance the idea that more complex song patterns are a response to difficult or demanding environments where female mockingbirds are likely to be on the lookout for a good provider.
Carlos Botero, a researcher at the National Evolutionary Synthesis Center, points out that male mockingbirds sing to attract a mate: "Complexity of song display - how many song types a bird sings, how hard the songs are - is a good predictor of the quality of the individual" he argues. "Males that sing more complex songs tend to carry fewer parasites and have offspring that are more likely to survive".
