Female reproductive system chemical communication

Species-specificity of chemicals and their role in reproductive isolation While there are general patterns in the chemical communication systems, there also seem to be species-specific differences. Some amphipod species appear unable to distinguish between mates and individuals of closely related species (Kolding 1986). Also in some isopod species, males pair with females from closely related species (e.g., Hargeby and Erlandsson 2006), which suggests that mate recognition via chemical cues is not (yet) fully developed. Possibly, selection on contact pheromones has been weak, because other life-history traits ensure reproductive isolation under natural conditions (e.g., size, habitat preference). 

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