Claw size of male fiddler crabs, Uca perplexa appears to be a target of female choice that increases the likelihood a female will initially approach a male. Here we show that a behavioral display trait, the maximum height that the tip of the claw reaches during a courtship wave, is a strong correlate of the subsequent likelihood that a female will visit a male's burrow (which is a prerequisite for a burrow mating). We experimentally manipulated claw mass, to test whether there is a trade-off between claw mass and wave height. Males with a metal weight added to their claw showed a large reduction in wave height, whereas control males (plastic added) showed no net change in wave height. There is therefore a trade-off between these two sexually selected traits (claw size and wave display). More importantly, the greater the initial wave height the smaller the subsequent decline in wave height. Assuming that variation in wave height is an index of quality, this variation in the cost-benefit trade-off is consistent with the requirements of a signaling system that conforms to the handicap principle when fitness is the multiplicative product of different fitness components. We conclude by discussing the ongoing difficulties in testing the handicap principle.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 63 • No. 9