Variation in communication systems

Geographical variation in male response also appears to be documented in the noctuid Agrotis segetum. The attractant components Z5-10 Ac, Z7-12 Ac and Z9-14 Ac and their blends that evoke male catch appear to differ in Denmark, Switzerland, France and Hungary (Arn et al., 1982). Geographical differences in pheromone production and response occur in Ostrinia nubilalis, the European corn borer, and will be considered in Section 13.3.6. 

Interpretation of the published attraction spectra of different populations of 

We know even less about the ratio of emitted pheromone components. The variance in ratio of the Zll and El 1-14 Ac components extracted from the pheromone gland has been determined for A. velutinana (Miller and Roelofs, 1980), and for various strains of O. nubilalis (see Section 13.3.6), but as yet we do not know if these ratios remain constant over time in individuals or if the ratios in the pheromone gland match the ratios actually released. 

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