Modifications et adaptations du rythme circadien d'activité sexuelle de plusieurs populations d'Acrolepiopsis assectella (Lepidoptera) originaires de différentes latitudes
Auteur : Thibout (Éric)
Année de publication : 1981
Publication : Biology of Behaviour
Volume :
6
Fascicule : 3
Pagination : 215-228
Résumé :
The frequency and the mean time of matings are compared in various populations of the leek-moth, A. assectella (Sweden, Tours area [France], Spain and Algeria), to study the adaptive significance of the sexual rhythm. In 14 h light, 10 h dark and constant temperature (25.degree. C), differences appear in the mean time of the nightly matings. Algerian strains mate earlier than Swedish and Tours strains, while Spanish strain mates later. In continuous light, after a temperature decrease from 25.degree.-17.5.degree. C mating frequency is not the same for every population. Though it is difficult to find a direct link between mating rhythm and geographic origin, some relations, particularly between the mean time of matings and the relative humidity rhythm in summer, can be observed. The exogenous regulation of the endogenous mating rhythm by light and temperature may be an adaptation to hazardous hygrometric rhythm. This shows the importance of selective pressures and the role of statistical relations which can link them. The populations of Sweden, Spain and Algeria have been crossed with a strain of the Tours area. The matings occur in every cross and the hybrids are fertile. The mating rhythms of these hybrids are very irregular and no conclusions can be drawn on the hereditary characteristics of the sexual rhythms