Background matching, disruptive coloration, and differential use of microhabitats in two neotropical grasshoppers with sexual dichromatism

Abstract

Cryptic coloration is an adaptative defensive mechanism against predators. Color patterns can become cryptic through background coloration‐matching and disruptive coloration. Disruptive coloration may evolve in visually heterogeneous microhabitats, whereas background matching could be favored in chromatically homogeneous microhabitats. In this work, we used digital photography to explore the potential use of disruptive coloration and background matching in males and females of two grasshopper species of the Sphenarium genus in different habitats. We found chromatic differences in the two grasshopper species that may be explained by local adaptation. We also found that the females and males of both species are dichromatic and seem to follow different color cryptic strategies, males are more disruptive than females, whereas females have a high background matching with less disruptive elements. The selective pressures of the predators in different microhabitats and the differences in mobility between sexes may explain the color pattern divergence between females and males. Nevertheless, more field experiments are needed in order to understand the relative importance of disruptive and background matching coloration in the evolution of sexual dichromatism in these grasshoppers.

Testing background matching and disruptive colouration in a sexually dichromatic grasshopper: a computer detection experiment

“…This is especially important in organisms with high mobility (Stevens et al, 2006). Moreover, if females and males use distinct microhabitats owing to their different sexual roles, and/or display differences in mobility, natural selection can favour a divergence in cryptic colour patterns between females and males (Forsman & Appelqvist, 1999; Medina et al, 2016; Ramírez‐Delgado & Cueva del Castillo, 2020; Cueva del Castillo et al, 2021).…”

“…However, the females tend to be cryptic to decrease the risk of being predated, whereas males are conspicuous due to sexual selection pressures (Badyaev & Hill, 2003; Medina et al, 2017). In invertebrates, the study of the evolution of sexual dimorphism in colour patterns has focused on insects, mainly orthopterans and butterflies (Forsman & Appelqvist, 1999; Ramírez‐Delgado & Cueva del Castillo, 2020; van der Bijl et al, 2020; Cueva del Castillo et al, 2021), but also spiders (Li et al, 2008). In orthopterans, evidence suggests that males and females could have different ecological niches and mobility that may favour divergence in colouration.…”

Towards Deeper Understanding of Camouflaged Object Detection

“…C AMOUFLAGE is an important tool for animals to reduce the probability of being detected or recognized [2], [3], [4], [5]. In order to hide in the environment, animals are evolved to share similar patterns with their habitats to reduce the intensity of their distinctive signals or enhance the confusing signals.…”

“…In order to hide in the environment, animals are evolved to share similar patterns with their habitats to reduce the intensity of their distinctive signals or enhance the confusing signals. Specifically, background matching and disruptive coloration [4], [5] are two main strategies that are widely adopted as anti-predator defences to achieve camouflage. The former changes the appearance of prey by capturing and imitating the color and pattern from the background, thereby blending in the environment [5].…”

“…Specifically, background matching and disruptive coloration [4], [5] are two main strategies that are widely adopted as anti-predator defences to achieve camouflage. The former changes the appearance of prey by capturing and imitating the color and pattern from the background, thereby blending in the environment [5]. The latter offers the high-contrast markings near the body edges and breaks the true edges that act as the salient cue [2].…”