Different environmental factors are important for development, physiology, behaviour and, therefore, adaptation of Drosophila species. Additionally, the presence of genetic and phenotypic variation in traits affecting mate choice forms the basis for sexual selection that may lead to isolation between populations in different nutritive environments. The aim of this research was to determine mating success and wing morphometry of Drosophila melanogaster flies after more than a decade of growing on banana and carrot substrates. Males and females reared on carrot medium were more successful in mating than flies reared on banana diet. Females originating from banana medium rather chose males originating from carrot substrate, while females developed on carrot medium equally chose males developed on both substrates. Differences in wing size and shape were observed between sexes and nutritional strains. Furthermore, the results showed absence of ethological isolation between two ‘nutritional’ strains.
Sexual size and shape dimorphism (SSD and SShD) are understudied phenomena in millipedes. In the present study, we investigated both kinds of sexual dimorphism in some morphological traits, as well as whether shape of the morphological traits varied more than their size. Three julidan species, viz., Pachyiulus hungaricus (Karsch, 1881), Megaphyllum unilineatum (C.L. Koch, 1838), and M. bosniense (Verhoeff, 1897), were used for these purposes. By means of traditional and geometric morphometrics, we found that SSD exists in linear measurements of the tested morphological traits, as well as SShD of the legs in all analysed species. Also, SSD of antennal centroid size was detected in P. hungaricus and M. unilineatum, in addition to SShD of antennae in P. hungaricus and M. bosniense. Our results indicate that morphological intersexual differences are species-specific and that the shape of some morphological traits varies more than the size of centroids of the same structures.