The influence of genes for melanism on the activity of the flour moth, Ephestia kuehniella.

We investigated the effects of genes controlling melanism on levels and patterns of activity, potential nonvisual components of fitness, of adult Mediterranean flour moths, Ephestia kuehniella Zeller (1879). Six genotypes of two melanic strains (Ala nigra and black) were used. We monitored continuously the walking or flight activity of 45 mated females per genotype during the third night of their lives, using automatic electrostatic techniques to carry out the measurements. Although there was high individual variation within genotypes, bb (melanic) females were more active than the two nonmelanic genotypes of the black strain (b+, ++) because they tended to show more bouts of activity. There were no differences in the average length of these bouts, or in the timing of initial and final activity. Overall, the females of the black strain were significantly more active than the females of the Ala nigra strain. The results are discussed in the context of the evolution of melanism in moths. Copyright 1998 The Association for the Study of Animal Behaviour