Honest Advertising, Sexual Selection, Courtship Displays, and Body Condition of Polygynous Male Harriers
In polygynous Northern Harriers (Circus cyaneus) aerial displays reflect male body condition, and displays are therefore difficult to fake. The most vigorously displaying males attract the largest harems, and such displays are an accurate measure of a male's potential to provision their mates (the single most important influence on female fecundity).
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