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Asynchrony in population abundance can buffer the effects of environmental change leading to greater community and ecosystem stability. Both environmental (abiotic) drivers and species functional (biotic) traits can influence population dynamics leading to asynchrony. However, empirical evidence linking dissimilarity in species traits to abundance asynchrony is limited, especially for understudied taxa such as insects. To fill this knowledge gap, we explored the relationship between pairwise species trait dissimilarity and asynchrony in interannual abundance change between pairs of species for 422 moth, butterfly, and bumblebee species in Great Britain. We also explored patterns differentiating traits that we assumed to capture 'sensitivity to environmental variables' (such as body mass), and traits that may reflect 'diversity in exposure' to environmental conditions and lead to niche partitioning (for example, habitat uses, and intra‐annual emergence periods). As expected, species trait dissimilarity calculated overall and for many individual traits representing response and exposure was positively correlated with asynchrony in all three insect groups. We found that 'exposure' traits, especially those relating to the phenology of species, had the strongest relationship with abundance asynchrony from all tested traits. Positive relationships were not simply due to shared evolutionary history leading to similar life‐history strategies: detected effects remained significant for most traits after accounting for phylogenetic relationships within models. Our results provide empirical support that dissimilarity in traits linked to species exposure and sensitivity to the environment could be important for temporal dissimilarity in insect abundance. Hence, we suggest that general trait diversity, but especially diversity in 'exposure' traits, could play a significant role in the resilience of insect communities to short‐term environmental perturbations through driving asynchrony between species abundances. [ABSTRACT FROM AUTHOR]

In Britain, most butterfly species reach the limit of their range due to climate. Such species are the ones most likely to show rapid adaptations to climate change. There are indications that several butterfly species are adapting and that these insects make good indicators of the likely effects of climate change on other animals. [ABSTRACT FROM AUTHOR]

The heath fritillary butterfly, Mellicta athalia, is an endangered species in Britain and has been the subject of a detailed study in 1980–85. M. athalia is found in three types of habitat in which it uses a range of different host-plants: (i) newly cleared woodland where its sole host is Melampyrum pratense; (ii) rough, unimproved grassland where its main, primary hosts are Plantago lanceolata and Veronica chamaedrys; (iii) sheltered heathland where its main, primary host is Melampyrum pratense. Eggs are laid in large batches on plants close to the ground, chiefly in open, sunny situations. In woodland habitats some eggs are laid in fairly shady situations, but always close to sunny clearings. A large range of host-plants was observed in the field, but the range used by adult females was rather narrower than that of the larvae. One secondary host, Digitalis purpurea, which was commonly used by post-diapause larvae in heathland habitats, was apparently never used by egg-laying females. In captivity, pre-diapause larvae failed to survive on this plant but post-diapause larvae grew as quickly on it as on other hosts. Considerable variation was observed in the phenology of M. athalia between both years and regions. In the predominantly grassland habitats in Cornwall, the adult population peaked 2–3 weeks earlier than in the woodland habitats in Kent. In both regions a close relationship was found between the date of the peak flight period and the temperature during April and May when the post-diapause larvae were developing. The regional difference in phenology was therefore thought to be caused by climatic differences, but a habitat effect could not be ruled out. The host selection and phenology of M. athalia in the different habitats and regions are discussed. [ABSTRACT FROM AUTHOR]