All About Birds : Uncertainty Breeds Cooperation in Birds, Study Finds
[[ ) is a complex cooperative breeder that lives in large family groups throughout the savannas of East Africa. Social groups can contain as many as 30 individuals. Photo by Dustin Rubenstein, Kenya ]]
[[ “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, who initiated the study as part of his graduate work in the Fuller Evolutionary Biology Program at the Cornell Lab of Ornithology. He received his doctorate from Cornell University in May 2006. ]]
[[ “It’s similar to the way humans group together in the face of uncertainty and buy mutual funds: we’re pooling our risk and working together to mitigate an uncertain future,” added Lovette, director of the Fuller Evolutionary Biology Program. “Birds that breed in groups buffer the effects of an uncertain environment.” ]]
{{ The Greater Blue-eared Glossy-Starling (Lamprotornis chalybaeus) }}
{{ lives in savanna woodland in West, Eastern, and Southern Africa. It is a non-cooperative breeder. Photo by Dustin Rubenstein, Kenya }}
{{ To look for patterns in the breeding behaviors of starlings and the environments in which they live???including savannas, deserts, and tropical forests???Rubenstein and Lovette examined rainfall patterns at thousands of African sites over more than a century. }}
{{ To consider the evolutionary relationships among dozens of starling species, they also collected starling DNA samples from museums and from expeditions to East Africa, where they dodged lions, African buffalo, rhinos, and other wildlife to capture the birds. Using the DNA, they constructed an evolutionary tree that showed how breeding behavior has evolved over millions of years. }} |
