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A comprehensive phylogeny of north European Geometridae is reconstructed using a two‐step analytical pipeline. First, a phylogenomic backbone tree was inferred using a 117‐species subset of geometrid moths and a 35‐species set of outgroup taxa from eight other macroheteroceran families. The data matrix totalled 209,499 bp from 648 protein‐coding loci obtained using anchored hybrid enrichment technique for sequencing. This backbone was used for constructing a larger phylogeny of Geometridae based on up to 11 'traditional' protein‐coding genes which were obtained for all 376 species of north European geometrids, complemented by 98 species from taxonomic key groups of Geometridae from other parts of the world. Our results largely corroborate earlier findings about higher classification of Geometridae, but new evidence nevertheless allows us to suggest several changes to the taxonomy. Lampropterygini Õunap & Nedumpally tribus nova and Pelurgini Õunap & Nedumpally tribus nova (both Larentiinae) are described. Epirranthini are regarded as a junior subjective synonym of Rumiini syn. n. Triphosini and Macariini are shown to be paraphyletic within their current limits. Costaconvexa Agenjo is transferred from Xanthorhoini to Epirrhoini new tribe association, Artiora Meyrick from Ennomini incertae sedis to Boarmiini new tribe association, Selenia Hübner from Ennominae incertae sedis to Epionini new tribe association and Epirranthis Hübner from Epirranthini to Rumiini new tribe association. Ochyria Hübner stat. rev. is revived from synonym of Xanthorhoe Hübner as a valid genus and Epelis Hulst stat. rev. and Speranza Curtis stat. rev. from synonyms of Macaria Curtis as valid genera, leading to the following new or revised combinations: Ochyria quadrifasiata (Clerck) rev. comb., Epelis carbonaria (Clerck) comb. n., Speranza fusca (Thunberg) comb. n., Speranza artesiaria (Denis & Schiffermüller) rev. comb., Speranza brunneata (Thunberg) rev. comb., Speranza wauaria (Linnaeus) rev. comb., Speranza loricaria (Eversmann) rev. comb.Perizoma saxicola Tikhonov rev. comb. is transferred back to its original genus from Gagitodes Warren. Hydrelia Hübner, Xanthorhoe and Heliomata Grote & Robinson are shown to be paraphyletic within their current limits. [ABSTRACT FROM AUTHOR]

Natural enemies play a key role in population dynamics of insects and exert significant selective pressures on various traits of these animals. Although there is a wealth of empirical and theoretical research on predators and parasitoids, the ecological role of pathogens (other than viruses) remains less understood. Entomopathogenic fungi (EPF), encompassing over 1000 known species from 11 phyla, have primarily been studied in the context of biocontrol in agroecosystems, while their role in natural ecosystems is poorly known. In this paper, we synthesize case studies reporting the prevalence of EPF infections in field populations of insects. We examine differences in this variable among major host taxa and those of the pathogens. From 79 case studies that met our selection criteria, we retrieved data on 122 species of fungi infecting 104 insect species. The meta‐analytic median prevalence of fungal infections was 8.2%; even if likely inflated by publication bias, this suggests that EPF‐induced mortality levels are lower than those attributable to predators and parasitoids. We found no substantial differences in fungal prevalence among major insect taxa and only a moderate difference among fungal orders, with Neozygitales showing the highest prevalence and Eurotiales the lowest. Our analysis revealed no significant differences in overall EPF prevalence between tropical and temperate studies, although different fungal taxa showed different geographical patterns. In temperate areas, there is some evidence of increasing infection prevalence toward the end of the growing season. Although quantitative data on the effect of EPF on insect populations are still scarce, evidence is consistent with the emerging generalization that insect populations commonly harbor species‐rich assemblages of pathogenic fungi, but infections rarely reach epidemic levels. Further studies on multi‐species assemblages of EPF associated with natural insect populations are needed to better understand the ecological role of fungal infections. [ABSTRACT FROM AUTHOR]

Interspecific variation in body size is one of the most popular topics in comparative studies. Despite recent advances, little is known about the patterns and processes behind the evolution of body size in insects. Here, we used a robust data set comprising all geometrid moth species occurring in Northern Europe to examine the evolutionary associations involving body size and several life-history traits under an explicitly phylogenetic framework. We provided new insights into the interactive effects of life-history traits on body size and evidence of correlated evolution. We further established the sequence of trait evolution linking body size with the life-history traits correlated with it. We found that most (but not all) of the studied life-history traits, to some extent, influenced interspecific variation in body size, but interactive effects were uncommon. Both bi- and multivariate phylogenetic analyses indicated that larger species tend to be nocturnal flyers, overwinter in the larval stage, feed on the foliage of trees rather than herbs, and have a generalist feeding behaviour. We found evidence of correlated evolution involving body size with overwintering stage, host-plant growth form, and dietary specialization. The examination of evolutionary transitions within the correlated evolution models signalled that overwintering as larvae commonly preceded the evolution of large sizes, as did feeding on tree foliage and the generalist feeding behaviour. By showing that both body size and all life-history traits correlated with it evolve at very slow rates, we caution against uncritical attempts to propose causal explanations for respective associations based on contemporary ecological settings. Graphical Abstract [ABSTRACT FROM AUTHOR]

Locomotory performance is an important determinant of fitness in most animals, including flying insects. Strong selective pressures on wing morphology are therefore expected. Previous studies on wing shape in Lepidoptera have found some support for hypotheses relating wing shape to environment-specific selective pressures on aerodynamic performance. Here, we present a phylogenetic comparative study on wing shape in the lepidopteran family Geometridae, covering 374 species of the northern European fauna. We focused on 11 wing traits including aspect ratio, wing roundness, and the pointedness of the apex, as well as the ratio of forewing and hindwing areas. All measures were taken from images available on the internet, using a combination of tools available in Fiji software and R. We found that wing shape demonstrates a phylogenetically conservative pattern of evolution in Geometridae, showing similar or stronger phylogenetic signal than many of its potential predictors. Several wing traits showed statistically significant associations with predictors such as body size, phenology, and preference for forest habitats. Overall, however, all of these associations remained notably weak, with no wing shape being excluded for any value of the predictors, including body size. We conclude that, in geometrids, wing traits do not readily respond to selective pressures optimizing aerodynamic performance of the moths in different environments. Selection on wing shape may nevertheless operate through other functions of the wings, with the effectiveness of crypsis at rest being a promising candidate for further studies. [ABSTRACT FROM AUTHOR]

Dry body mass (DBM) is perhaps the most biologically informative variable describing body size in invertebrates. Unfortunately, obtaining species-specific indices of DBM is problematic because body mass inevitably changes during the course of the life of an individual. Here, we present a phylogenetically informed analysis of allometric relationships between body size and various linear measurements in the moth family Geometridae, which relies on DBM recorded at a fixed time point of adult life. We demonstrate that all measurements of wing size predict DBM with reasonable accuracy, with the distance between the most distal ends of the two forewings in traditionally mounted moths showing the best performance. Abdomen width provides independent morphometric information and can be used as a proxy of body plan, i.e. a measurement of shape that is not dependent on size. Incorporating abdomen width into the regression models considerably increases their predictive ability. We also show that the allometric relationships are reasonably consistent between the two sexes, between monophyletic clades of Geometridae and between the two geographical regions involved in the study (northern Europe and equatorial Africa). The derived equations thus appear to be general enough to be applied in various studies, from comparative phylogenetic analyses to applied projects monitoring insect biomass. [ABSTRACT FROM AUTHOR]

Temperature has a profound effect on the growth and development of ectothermic animals. However, the extent to which ecologically driven selection pressures can adjust thermal plastic responses in growth schedules is not well understood. Comparing temperature‐induced plastic responses between sexes provides a promising but underexploited approach to evaluating the evolvability of thermal reaction norms: males and females share largely the same genes and immature environments but typically experience different ecological selection pressures. We proceed from the idea that substantial sex differences in plastic responses could be interpreted as resulting from sex‐specific life‐history optimization, whereas similarity among the sexes should rather be seen as evidence of an essential role of physiological constraints. In this study, we performed a meta‐analysis of sex‐specific thermal responses in insect development times, using data on 161 species with comprehensive phylogenetic and ecological coverage. As a reference for judging the magnitude of sex specificity in thermal plasticity, we compared the magnitude of sex differences in plastic responses to temperature with those in response to diet. We show that sex‐specific responses of development times to temperature variation are broadly similar. We also found no strong evidence for sex specificity in thermal responses to depend on the magnitude or direction of sex differences in development time. Sex differences in temperature‐induced plastic responses were systematically less pronounced than sex differences in responses induced by variations in larval diet. Our results point to the existence of substantial constraints on the evolvability of thermal reaction norms in insects as the most likely explanation. If confirmed, the low evolvability of thermal response is an essential aspect to consider in predicting evolutionary responses to climate warming. [ABSTRACT FROM AUTHOR]

Simple Summary: Sugar baits are not only used to attract butterflies; they are also used to attract nocturnal moths. Similarly to most sampling techniques, the results of bait trapping are influenced by ambient conditions. In order to understand how bait trap catches depend on weather parameters, we performed a study in the north European forest zone using portable weather stations placed next to the traps. We found that the number of moths caught was strongly positively dependent on temperature and negatively dependent on air humidity. Diversity showed a similar dependence on temperature and humidity but was also negatively affected by air pressure and positively affected by the change of pressure during the night. Our findings help to interpret the results of quantitative insect trapping projects as they allow one to properly account for variability in weather conditions. Assemblages of insects need to be quantitatively sampled in the context of various research questions. Light trapping is the most widely used method for sampling nocturnal Lepidoptera. Attracting moths to sugar baits offers a viable alternative. However, this method is rarely used in professional research despite its popularity among amateur lepidopterists. As the activity of insects is strongly dependent on ambient conditions, the sensitivity of any trapping method to weather parameters needs to be known for the quantitative interpretation of trapping results. In the present paper, we report data on the weather dependence of moth catches obtained by automatic bait traps. The study was performed in Estonia, representing the European hemiboreal forest zone. Portable weather stations set up next to each of the traps were used for collecting weather data. Both abundance and diversity of the moths in the catches depended strongly positively on temperature and negatively on air humidity. Diversity was also negatively correlated with air pressure and positively with the change in pressure during the night. The results show that in situ recording of weather parameters in connection to insect trapping provides useful insights for the study of insect behaviour and the interpretation of the results of monitoring projects. [ABSTRACT FROM AUTHOR]

The degree to which variation in adult food availability affects the population dynamics of a species depends on its position on the capital‐income breeding continuum. The long‐lived butterflies that feed on fruits as adults constitute an example of Lepidoptera with a high degree of income breeding.For three species of fruit‐feeding butterflies in Uganda, we assessed the contribution of income to breeding in the wild, and the consequences of variation in fruit availability for body mass and population dynamics. We interpreted body‐mass loss within individuals as well as younger individuals having higher body mass than older ones as evidence for the depletion of capital reserves.Despite large sample sizes, we were able to show only modest body‐mass loss in one species, indicating that large‐bodied fruit‐feeding butterflies are functionally income breeders in the wild. Butterfly body mass was sensitive to environmental factors, although the responses to fruit availability and weather parameters were dominated by interactive effects. In all three species, periods of higher availability of fruit were followed by periods of higher adult abundance three to five months later, fitting the egg‐to‐adult time.Our results suggest that adult food is rapidly used for reproduction so that body mass remains stable and population size responds to adult food availability.For these income breeding species, the frequent periods of low adult food availability may select for extended adult longevity for the purpose of postponing reproduction to the onset of more favourable conditions. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]