Semelhantes, mas não iguais: escolha de parceiros intra e interpopulacional no caranguejo chama-maré Leptuca leptodactyla (Rathbun, 1898)

Abstract

The body coloration of fiddler crabs is especially relevant in recognizing conspecifics and choosing reproductive partners. The color of fiddler crabs can vary within a population, due to factors such as age and body condition, and between populations, due to environmental differences in each location, such as different predation pressures or food composition. In the present study, we investigated the influence of body color of the fiddler crab Leptuca leptodactyla on the selection of reproductive partners. We tested the following hypotheses: 1) females use the natural variation of some of the colorimetric variables (i.e., brightness, hue or saturation) when choosing their reproductive partners; 2) females prefer males from their own population over males from another population; 3) females prefer lighter males over darker males. To test these hypotheses, we performed dichotomous mate choice tests in a natural environment, which consisted of offering L. leptodactyla females the option between two males from the same population to test intrapopulation preference, and males from two populations to test interpopulation preference. We also measured the color of the males' hypertrophied chelipeds with a spectrophotometer. The analyses of color measurements were carried out using the ‘pavo’ package, in the R software (R Development Core Team). The results showed that, when given the option between two males from their own population, females preferred males with higher brightness. On the other hand, when confronted with local males and males from another population, females preferred local males, possibly basing this preference on information on the saturation of the hypertrophied cheliped, which differs significantly between the populations studied. Our findings provide a better understanding of the role of body color in the selection of reproductive partners in the fiddler crab L. leptodactyla. We demonstrate that natural variation in the color of the hypertrophied cheliped influences female preference for reproductive partners and that this preference can vary between populations.