Speciation, sexual selection, and the macroevolution of cricket mating signals

Mating signals that serve as species-specific recognition cues and indicators of male quality are known to evolve rapidly during the initial stages of species formation, according to a recent study. The research, which examined a wide range of species within a single group, reveals that these recognition-related signals undergo swift divergence right after the formation of a new species, only to stabilize at an equilibrium point later on. This pattern is particularly pronounced in species pairs that have the potential for interbreeding.

Interestingly, the study also found that mating signals associated with sexual selection, which are meant to persuade females to mate with a particular male, do not exhibit this same pattern of rapid divergence. Instead, the evolution of these persuasion signals occurs independently of initial species divergence.

These findings challenge the common belief that traits under intense sexual selection are the primary drivers of speciation. The researchers suggest that the connection between sexual selection and speciation is not as strong as previously thought, and may only be temporary. The study indicates that recognition traits, which help females differentiate between their own species and others, are crucial for speciation, and their divergence plays a key role in the process.

This distinction between recognition and persuasion traits, and the importance of recognition trait divergence for speciation, is expected to be a common occurrence across many species.