Twenty-two of 32 felids were classed as spotted, six as uniform, two as horizontally striped and two as vertically striped. Ortolani & Caro were aware that their method of subjective classification of patterning as either uniform, spotted, horizontally or vertically striped may have masked important variety in felid patterning (so reducing statistical power). Overall, their results supported the hypothesis that felid flank patterns evolve to match the visual appearance of the background. There was some support for vertical stripes emerging in species using grasslands and terrestrial locomotion when examining all carnivores in the more extensive dataset used by Ortolani, perhaps due to greater statistical power, as well as for an association between dark horizontal stripes and arboreal locomotion. In the study of Ortolani & Caro, there was no association between vertically striped coats and utilization of grassland habitats in either felids or all carnivores. Similarly, Ortolani found support for dark spots on carnivores being associated with closed habitats, arboreal locomotion and preying on ungulates. Across all carnivores, this association between spots and forested habitats approached significance and spots were significantly associated with arboreality. Ortolani & Caro used a concentrated changes test to find a significant association in felids between losing spotted coats and absence from forested environments. Two studies have previously examined felid patterning using the comparative method. Many smaller cats are also likely to be camouflaged for protection from predation. As hunts are more successful when an attack is initiated from shorter distances, cats benefit from remaining undetected for as long as possible and camouflage helps achieve this. The primary hunting strategy of felids is to stalk prey until they are close enough to capture them with a pounce or quick rush. Previous studies of the adaptive function of cat coat patterns have indicated that they are likely to be for camouflage rather than communication or physiological reasons. The patterns displayed on the flanks of felids are intriguing in their variety. Our method could be applied to any taxon with colour patterns that can reasonably be matched to reaction–diffusion and similar models, where the kinetics of the reaction between two or more initially randomly dispersed morphogens determines the outcome of pattern development. Furthermore, we show that there is little phylogenetic signal in the visual appearance of felid patterning, indicating that camouflage adapts to ecology over relatively short time scales. Our analysis also indicates that disruptive selection is a likely explanation for the prevalence of melanistic forms in Felidae. We found that likelihood of patterning and pattern attributes, such as complexity and irregularity, were related to felids' habitats, arboreality and nocturnality. After controlling for the effects of shared ancestry using a fully resolved molecular phylogeny, this study shows how phenotypes from plausible felid coat pattern generation mechanisms relate to ecology. This study examines variation in the camouflage patterns displayed on the flanks of many felids. However, only two previous studies, which involved computer-generated evolving prey, have attempted to make this link. A complete explanation of the diversity of animal colour patterns requires an understanding of both the developmental mechanisms generating them and their adaptive value.
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