The "Chameleon Ant" Colobopsis imitans Adapts Its Mimetic Appearance to Local Model Species Across the Mediterranean Basin (Hymenoptera: Formicidae).

Mimicry, where an organism (the mimic) convergently evolves traits resembling another (the model), is one of the most compelling phenomena in evolutionary biology. Despite ants frequently serving as models for Batesian mimics in other arthropod taxa, mimicry among ants is still underexplored. Rapid mimetic adaptations may superficially suggest a pathway to speciation; therefore, a thorough exploration of the phenomenon requires multivariate analyses. Consequently, we collected morphometric data from Colobopsis samples across the Mediterranean Basin and the Caucasus, documented color patterns of mimics and local models, and performed unsupervised multivariate analyses to examine evolutionary dynamics in the Mediterranean Colobopsis mimicry system. Our central questions were whether adaptive color changes in regional mimic populations reflect distinct evolutionary lineages leading to speciation or represent intraspecific responses to local environmental pressures, that is, adjustment to locally available models. We sought morphometric discontinuities in morphospace that might indicate the existence of distinct lineages among mimic populations with different color schemes. Biogeographic analyses show that Colobopsis imitans Schifani et al., 2022 replaces Colobopsis truncata (Spinola, 1808) throughout southern Europe and displays remarkably versatile region-specific mimetic visual adaptations to local model species-hence the title analogy; this species is a true chameleon, in a biogeographical sense. Our research presents a scenario where mimicry-driven microevolutionary adaptations can produce significant phenotypic diversity without leading to speciation.