Specific mate recognition systems

In aquatic systems, solubility takes the place of volatility. Aquatic pheromones can be large molecules so long as they are soluble in water (though contact pheromones, such as those used in mate recognition in shrimp and copepods are presumably almost insoluble - see e.g., Bauer, Chap. 14 and Snell, Chap. 23). Many aquatic organisms use polypeptides as pheromones, for example the crab pumping pheromone (Rittschof and Cohen 2004). Pheromone specificity can be gained by... 

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). 

One perceives from the world only what one has been prepared to perceive. In humans and in most mammals, different senses are used to make sense of life. In contrast, in insects, chemical senses involving odorants and contact chemosensory molecules play a vital role. The olfactory system is the primary sense insects use in analyzing the environment, in crucial tasks such as finding food, nesting, mating and in conspecifics. Contact chemosensation is used especially to analyze specific substrates to assist in the identification of suitable oviposition sites, the recognition of host plants, the selection of tastants and the search for further nutrient chemicals. Dedicated to survival, both olfactory and contact chemosensory systems in insects have developed to extremely high levels of sensitivity and selectivity. 

And then there is finally - besides the artificial evolutions of selecting functional nucleic acids for specific interactions with cooperative mates, high-affinic recognitions, and catalytic activities fiom random pools - the evolution of an individual scientific life s work [50], which itself follows decisive stages of the grand process the exploration of early chemical requirements, the development of prebiotic ligand systems, the fixation into the ordered structures of informational inorganic matrix patterns... 

Many sympatric tortricine moths possess overlapping chemical communication systems because at least one component of their pheromones is either a 14-carbon chain acetate, alcohol or aldehyde, with unsaturation in the Cn-12 position. The species recognition of distinctive pheromone blends, together with non-pheromonal reproductive isolating mechanisms such as habitat preferences and differential mating times have been discussed by Card et al 500). This article, together with the literature cited therein, should be read to obtain an informed view of pheromone specificity and its significance in tortricine moths. 

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