Influência de variáveis ambientais na coloração de caranguejos chama-maré

Abstract

The color in animals can play roles in intraspecific and interspecific communication and vary across parts or the entire body. Some animals have colors similar to the surrounding environment to become less perceptible to predators. Among the various animal groups, fiddler crabs exhibit many colors and patterns on their carapace and claw, where males display an enlarged claw that can be used for defense and to attract females. This study aims to determine the influence of habitat, substrate, and size on the coloration of the carapace and claw of fiddler crabs. Based on the available information in the scientific literature and human color perception from photos, it was observed that most species occur in muddy substrates and open environments, commonly displaying an orange claw and a green carapace. Additionally, it was found that larger individuals have a black-colored carapace. Although the animals generally have an orange claw contrasting with the dark mud background, making them more perceptible to predators, males with an enlarged claw experience less predation. The carapace, usually black or green, tends to resemble the color of the background, primarily involved in thermoregulation and camouflage. Therefore, several factors aim to explain the color of fiddler crabs based on the signal they wish to convey.