COVER Male rhinoceros beetles (Trypoxylus dichotomus) wield a huge forked horn on their heads. Sexual selection may favor the evolution of exaggerated trait sizes because the developmental mechanism responsible for increased growth also results in signal reliability. See page 860. Photo: Will Freihofer and Douglas Emlen3 `/ S m; @4 O( } : }. j& ~- H& s, g- v
发表于 2012-8-17 16:33
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发表于 2012-8-17 19:10
