Behavioural correlates of selection for oviposition by Drosophila melanogaster females in a patchy environment

Abstract

The behaviour of females from lines selected for high (H) and low (L) aggregated oviposition was compared in an environment consisting of discrete patches of resource available for larval development. Oviposition behaviour was influenced by the conformation and by the texture of the substrate, but this does not account for the selective differences in levels of aggregation which are under genetic control. The distribution of males of both selected populations tends to be overdispersed across resource patches. This observation is consistent with male territorial behaviour. The dispersal patterns of females of the two selected populations differ significantly. H females show a contagious distribution whereas the distribution for L females is more nearly random. Differences in adult female dispersion are likely to be a significant factor contributing to aggregated oviposition. The level of aggregated oviposition affects the pattern of progeny survival when the unit of resource in each patch is small.

Agar-polydimethylsiloxane devices for quantitative investigation of oviposition behaviour of adult Drosophila melanogaster

“…1), and the oviposition and viability of flies (25 females and 20 males) were quantitatively investigated. When compared to conventional oviposition assays, our technique has provided a Surface quality, texture, and chemistry have been shown to have significant effects on flies' oviposition, 24,25,30,31,[33][34][35][36][37] however, the required area of exposure to agar substrate, in order to keep a population of fruit flies alive and to induce them to lay their eggs naturally (i.e., similarly to pure agar substrates) were not investigated. Accordingly, our aim was to quantitatively investigate the effects and the threshold values of surface exposure area on oviposition of fruit flies using our PDMS membrane patterning technique.…”

“…melanogaster ovipositional assays, studying the effects of physical and chemical substrate factors on egg-laying behavior, were not highly controlled and lack repeatability and precision due to the use of manual texturing approaches. 30,31,34,35,47 Since they only provided crude results about oviposition behaviour in flies, the PDMS membrane patterning and agar chemical composition manipulation techniques were used to control exposure areas and textures, and to investigate oviposition both in batch format and at a single-egg resolution level. As described in Section II, thin PDMS membranes with patterned through-holes were designed (Table I) and overlaid on conventional agar-juice plates with various physical and chemical properties (Fig.…”

“…By using the additive texturing methodologies, more eggs were shown to be laid on certain substrates modified by silk meshes or seeded grapes. 30,31 However, due to the low mechanical stiffness of the silk meshes, their physical shapes were reported to be deformed upon implantation of the eggs. 30 Similarly, subtractive texturing methods have also provided the same conclusion that textured substrates induce more oviposition.…”

“…32 Current surface texture studies may be categorized into additive and subtractive texturing approaches. In the former method, seeded bisected grapes 31 or blotters, 33 silk meshes, 30 and different kinds of papers 30 (such as cardboard strips, filter paper, and Washi paper) on top of standard agar substrates have been used to produce different surface modifications. In the latter approaches, manually scratched agar plates 33,34 were used to produce texturized surfaces.…”

“…Thereby, development of a precise and sensitive method for accurate and quantitative analysis of oviposition is necessary. Current ovipositional assays in laboratory settings investigate the effect of environmental cues such as physical surface texture 30,31 and substrate chemical composition 25 on oviposition by using the standard yeast medium and the grape juice agar plates. 32 Current surface texture studies may be categorized into additive and subtractive texturing approaches.…”