Temperature–maternal age interactions on wing traits in outbred Drosophila mercatorum

Abstract

Drosophilid wings have often been used to investigate maternal effects of age and phenotypic plasticity in response to developmental temperature. However, temperature-maternal age interactions have been given little attention despite their potentially important role in driving evolution. Climatic change and anthropogenic intervention can possibly influence the age structure of a population, leading to a larger proportion of individuals reproducing at old age due to low recruitment. Here we investigated the morphometric traits wing length and wing width as well as the composite trait wing aspect (wing width/wing length) of the offspring of young (3 to 6 d) and old (15 to 18 d) mothers at 3 rearing temperatures (20, 25 and 28°C). We used 2 different strains of highly heterozygous, yet genetically identical, individuals. We found significant effects of maternal age and rearing temperature on wing size and wing shape characterised by PC1 and PC2, respectively; however, the interaction was highly significant only in Strain 2, but close to significant in Strain 1. The analysis of phenotypic plasticity of wing length in response to temperature did not reveal any difference between offspring of young and old mothers. For wing width, the response was significantly different from 20 to 25°C in Strain 1 but not in Strain 2. The composite trait, wing aspect, was highly significant from 20 to 25°C in Strain 1 and significant in Strain 2 from 25 to 28°C. The main implication of the observed results is that climatic factors, such as temperature, may interact with maternal effects of age to potentially exacerbate phenotypic plasticity.

Interplay between habitat fragmentation and climate change: inbreeding affects the response to thermal stress in Drosophila melanogaster

“…The reaction norms for the 2 wing size measures and for OB numbers of both the inbred and non-inbred populations show similar shapes, as found in other studies on Drosophila melanogaster using the same or comparable traits (e.g. Imasheva et al 1998, Gibert et al 2004, Kjaersgaard et al 2010, this Special, Trotta et al 2010.…”

Rapid responses to a strong experimental selection for heat hardening in the invasive whitefly Bemisia tabaciMEAM 1

“…For example, carryover effects are likely to be influencing thermal responses together with strong thermal selection (Magiafoglou & Hoffmann, 2003a;Amarillo-Su arez & Fox, 2006;Steigenga & Fischer, 2007;Kjaersgaard et al, 2010;Scharf et al, 2010;Schiffer et al, 2013;Kristensen et al, 2015). For example, carryover effects are likely to be influencing thermal responses together with strong thermal selection (Magiafoglou & Hoffmann, 2003a;Amarillo-Su arez & Fox, 2006;Steigenga & Fischer, 2007;Kjaersgaard et al, 2010;Scharf et al, 2010;Schiffer et al, 2013;Kristensen et al, 2015).…”

“…In addition to potential tradeoffs between fitness components, the nature of our selection regime also involved other changes unrelated to selection. For example, carryover effects are likely to be influencing thermal responses together with strong thermal selection (Magiafoglou & Hoffmann, 2003a;Amarillo-Su arez & Fox, 2006;Steigenga & Fischer, 2007;Kjaersgaard et al, 2010;Scharf et al, 2010;Schiffer et al, 2013;Kristensen et al, 2015). If we consider that adult founders of each generation of selection were exposed to thermal shocks in the previous generation, this exposure may have caused thermal damage that compromises their long-term fitness (Hoffmann et al, 2003).…”

Exploring plastic and genetic responses to temperature variation using copper butterflies

“…Such cross-generational plasticity most frequently involves interactions between mothers and their offspring, and has also been demonstrated in relation to temperature (maternal effects; Mousseau & Fox 1998, AmarilloSuárez & Fox 2006, Steigenga & Fischer 2007, Kjaersgaard et al 2010, this Special, Scharf et al 2010. Finally, spatial and/or temporal temperature variation may, over the long term, induce evolutionary (genetic) adaptation.…”