Study: Climate may affect birds' songs

DURHAM, N.C., May 26 (UPI) -- U.S. and Canadian scientists say climate patterns might be responsible for some birds singing elaborate songs and others much more simple melodies.

The researchers show that difference in song patterns among the many species of mockingbird vary with climate in the diverse places where the species live. Specifically, birds that are subject to more variable and unpredictable climates also have more impressive singing skills.

"Local climatic patterns are great indicators of how demanding life can be at a certain site," said Carlos Botero of the National Evolutionary Synthesis Center in Durham, N.C. "For example, harsher winters, drier dry seasons or highly unpredictable weather patterns make it harder for animals to survive and reproduce. Our data show that mockingbirds living in more demanding environments tend to have more elaborate song displays. We think that this surprising relationship reflects the fact that just as climatic patterns tell a lot about a site, singing behavior also tells a lot about a singer."

Male songbirds sing to attract mates and to repel rivals, Botero said. When the climate is less certain, the songs probably become even more critical as females become choosier in their mate selection.

The study that included Neeltje Boogert of McGill University and Sandra Vehrencamp and Irby Lovette of Cornell University appears in the only edition of the journal Current Biology.