Red-sided garter snakes (Thamnophis sirtalis parietalis) exhibit a remarkable mating strategy known as sexual mimicry.

During the mating season in early spring, large gatherings—often referred to as "mating balls"—form around emerging females, where dozens or even hundreds of males compete for a single female.

Some smaller or less competitive males adopt an unusual tactic: they emit female-like pheromones to mimic the scent of a female.

This tricks other males into courting them, which ironically provides a protective shield from predators due to the crowd, and it also allows the mimicking males to gain early access to real females by slipping into the mating ball unnoticed and unchallenged.

This strategy is temporarily reversible—once they reach a better competitive status or the opportunity arises, these mimics resume typical male behaviors.

This phenomenon is well-documented in behavioral ecology, particularly in the research of Dr. Robert Mason at Oregon State University, who studied their pheromonal communication.