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Figure 1. Florida scrub-jayClick to Enlarge Image

Florida scrub-jays work together to raise offspring. Consequently, some birds breed and others simply help raise the young. Many examples of cooperative breeding have been studied for decades, but virtually all studies have addressed the evolutionary cause—improvements in fitness—behind such a social system. By contrast, Schoech searches for the proximate, or immediate, factors that can drive a bird to help rather than breed. In the end, he reveals that helpers can be breeders, if they are given the chance. In other words, helpers are physiologically capable of breeding. In addition, he also found that levels of the hormone proclatin correlate with the quantity of helping behavior that a bird performs.

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