Uncertain rainfall makes birds cooperate
[[ and ]]
[[ Miyoko Chu ]]
[[ Rather than striking out to raise their family, members of some bird species cooperate to help raise their siblings, nephews, nieces, cousins -- or even unrelated young. Researchers have long noted which factors lead to these seemingly altruistic decisions, but now for the first time, Cornell researchers have linked a specific environmental factor to the evolution of cooperative family life in numerous bird species: unpredictable rainfall. ]]
{{ Dustin Rubenstein }}
{{ The lesser blue-eared glossy-starling ( }}
{{ Lamprotornis chloropterus }}
{{ ) lives in savanna woodland habitat throughout West and Southern Africa, as well as parts of East Africa. }}
{{ In the Aug. 21 issue of Current Biology, authors Dustin Rubenstein and Irby Lovette report that among African starlings, cooperative breeding is most common among species that live in savannas, where the rainfall varies greatly from one year to the next. }}
{{ "When you don't know what conditions you will be facing in the next breeding season, it pays -- in an evolutionary sense -- to live and breed in family groups because more chicks survive over the long haul," said lead author Rubenstein, Cornell Ph.D. '06, now at the University of California-Berkeley, who started the study as a graduate student in the Fuller Evolutionary Biology Program at the Cornell Lab of Ornithology. }} |
