THE ROLE OF CHEMICAL SIGNALS IS COPEPOD REPRODUCTION

Because the reproductive fitness of a copepod is influenced by its abi lity to discriminate between conspecific and heterospecific mates, it is important to understand the mechanisms involved in these complex ma te-recognition systems. Several lines of evidence suggest that chemica l communication plays a role in mate location, recognition and reprodu ction in copepods. However, the relative importance of chemosensory cu es, as well as other factors, including hydromechanical and morphologi cal cues, remains unclear. Some studies show that mating 'mistakes' oc casionally occur in nature, which for species that mate only once, wou ld have considerable effects on fitness. By reducing the likelihood of heterospecific matings, species-specific mate location and recognitio n chemicals have high adaptive value. The relative importance and mole cular characteristics of these chemicals, whether diffusible or contac t signals, may explain differences in premating and copulatory behavio r observed among different copepod taxa. Current research suggests tha t both forms of chemical communication significantly influence the rep roductive success of copepods. In this review, we summarize examples f rom the literature that may serve as a means to critically analyze pos tulated ideas and offer new questions for future study. (C) 1998 Elsev ier Science B.V. All rights reserved.