Mate Recognition, Species Boundaries and the Fallacy of “Species Recognition”

If speciation is typically a process of allopatric divergence following vicariance or dispersal, then a priori, we might expect that individuals of separate lineages typically will retain the ability to “recognize mates” across species boundaries, especially if some components of mate recognition experience strong stabilizing selection. Confusion results from an over-reliance on the importance of reproductive compatibility, as emphasized by proponents of the Biological Species Concept, in contrast to other characters indicative of phylogenetic history. Lack of divergence in premating courtship implies nothing about the nature of species boundaries; rather, it is best viewed as the retention of a plesiomorphic genomic compatibility, not a violation of species boundaries. Until evolutionary biologists recognize that mate recognition systems need not diverge for the attainment of lineage status, misdirected debate will continue. Only by accepting the observation that heterospecifics need not differ in mate recognition systems will additional examples be