Gender and Timing during Ontogeny Matter: Effects of a Temporary High Temperature on Survival, Body Size and Colouration in Harmonia axyridis
Open Access
- 25 September 2013
- journal article
- research article
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 8 (9), e74984
- https://doi.org/10.1371/journal.pone.0074984
Abstract
The ambient temperature experienced during development is a crucial factor affecting survival and adult phenotype in ectotherms. Moreover, the exact response of individuals to different temperature regimes is frequently sex-specific. This sex-specific response can result in varying levels of sexual dimorphism according to the experienced conditions. The majority of studies have investigated the effects of temperature on individuals reared under a constant temperature regime throughout their whole preimaginal development, whereas information on stage-dependent variation in temperature effects is scarce. Here we investigate how the stage at which elevated temperature is experienced influences survival, adult body size and colouration in the harlequin ladybird Harmonia axyridis form succinea. The effects of timing of exposure to elevated temperature on the adult phenotype are assessed separately for males and females. Control individuals were reared at a constant temperature of 20°C. Beetles in other treatments were additionally exposed to 33°C for 48 hours during the following developmental stages: egg, 1st to 2nd larval instar, 3rd larval instar, 4th larval instar and pupa. Exposure to an elevated temperature during the early developmental stages resulted in lower survival, but the adult phenotype of survivors was almost unaffected. Exposure to an elevated temperature during the later developmental stages (4th larval instar or pupa) resulted in the decreased melanisation of elytra, decreased structural body size and increased dry mass. Furthermore, the timing of high temperature exposure affected the degree of sexual dimorphism in elytral melanisation and dry mass. We demonstrate that the effects of elevated temperature can vary according to the developmental stage at exposure. Detailed information on how ambient temperature affects the developmental biology of ectotherms is crucial for modeling population growth and predicting the spread of invasive species such as Harmonia axyridis.This publication has 73 references indexed in Scilit:
- Gender- and stressor-specific microRNA expression in Tribolium castaneumBiology Letters, 2012
- Temperature-Dependent Development and Survival of Brazilian Populations of the Mediterranean Fruit Fly,Ceratitis capitata, from Tropical, Subtropical and Temperate RegionsJournal of Insect Science, 2012
- Record of the invasive alien ladybird Harmonia axyridis (Coleoptera, Coccinellidae) from KenyaZooKeys, 2011
- Sex differences in phenotypic plasticity of a mechanism that controls body size: implications for sexual size dimorphismProceedings. Biological sciences, 2010
- Phenotypic plasticity and population viability: the importance of environmental predictabilityProceedings. Biological sciences, 2010
- Bridgehead Effect in the Worldwide Invasion of the Biocontrol Harlequin LadybirdPLOS ONE, 2010
- Sex Differences in Phenotypic Plasticity Affect Variation in Sexual Size Dimorphism in Insects: From Physiology to EvolutionAnnual Review of Entomology, 2010
- Sexual selection mediated by the thermoregulatory effects of male colour pattern in the ambush bugPhymata americanaProceedings. Biological sciences, 2007
- Adult Size in Ectotherms: Temperature Effects on Growth and DifferentiationJournal of Theoretical Biology, 1996
- Evolution of thermal sensitivity of ectotherm performanceTrends in Ecology & Evolution, 1989