Ecological specialisation and range size determine intraspecific body size variation in a speciose clade of insect herbivores

The body size of an adult insect is strongly determined by the environmental factors to which it is exposed during growth and development. Insect species confronted with a high environmental variability across their geographical range (i.e., wide ecological niche breadth) may therefore reveal broader variation in body size than those species which are more specialised (i.e., narrow ecological niche). In this study, we aim to investigate whether characteristics related to the ecological niche breadth of a holometabolous insect species (i.e., its ecological specialisation) affect its intraspecific variation in adult body size. By using European geometrid moths as a model group, we specifically tested whether latitudinal range size, larval resource use, and voltinism affect intraspecific body size variation. We hypothesised that plasticity will increase along with latitudinal range and larval diet breadth. We further expected that univoltine species reveal a lower body size variation compa...

昆虫成虫的体型在很大程度上由其生长发育阶段所接触的环境因素决定。相较于生态特化程度更高（即生态位宽度（ecological niche breadth）较窄）的昆虫物种，地理分布范围内环境变异性较高（即生态位宽度较广）的昆虫类群，其体型的种内变异（intraspecific variation）幅度往往更为宽泛。本研究旨在探究全变态昆虫（holometabolous insect）物种的生态位宽度相关特征（即其生态特化程度）是否会对其成虫体型的种内变异产生影响。我们以欧洲尺蛾科蛾子（geometrid moths）作为模式类群，专门检验了纬度分布范围、幼虫寄主利用策略以及化性（voltinism）是否会影响种内体型变异。我们提出假说：体型可塑性会随纬度分布范围与幼虫食性广度的扩大而提升。我们进一步预期，一化性（univoltine）物种的体型变异程度相对更低……