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1. Comparative studies on insect life histories are facilitated by the increasing availability of reliable phylogenies but are hampered by the scarcity of comparable data. Fortunately, morphological proxies of some life‐history traits can be measured on preserved specimens. 2. This study compared values of size‐related life‐history traits among a tropical (Ugandan) and a temperate (Estonian) assemblage of geometrid moths. 3. A comparative analysis based on an originally derived phylogeny revealed that tropical moths were, on average, larger than temperate ones. Tropical moths also had somewhat lower relative abdomen masses than temperate ones. This indicates that the tropical rather than the temperate moths tend to use an income (rather than capital) breeding strategy. Nevertheless, no difference was found in a related index of pro‐ovigeny. When body size was accounted for, tropical moths were found to lay smaller eggs than temperate ones. 4. The differences between the two compared areas are consistent with selection on higher mobility of the moths imposed by the more diverse tropical vegetation. Relatively larger eggs of temperate moths may constitute an adaptation to overcome the presumably stronger quantitative defences of their host plants. 5. Overall, however, we conclude that the differences in ecologically relevant size‐related traits are relatively low among moth assemblages of a tropical and a temperate forest region, indicating that these environments may not impose radically different selective pressures on insect life histories.

Sexual traits are often the most divergent characters among closely related species, suggesting an important role of sexual traits in speciation. However, to prove this, we need to show that sexual trait differences accumulate before or during the speciation process, rather than being a consequence of it. Here, we contrast patterns of divergence among putative male sex pheromone (pMSP) composition and the genetic structure inferred from variation in the mitochondrial cytochrome oxidase 1 and nuclear CAD loci in the African butterfly Bicyclus anynana (Butler, 1879) to determine whether the evolution of “pheromonal dialects” occurs before or after the differentiation process. We observed differences in abundance of some shared pMSP components as well as differences in the composition of the pMSP among B. anynana populations. In addition, B. anynana individuals from Kenya displayed differences in the pMSP composition within a single population that appeared not associated with genetic differences. These differences in pMSP composition both between and within B. anynana populations were as large as those found between different Bicyclus species. Our results suggest that “pheromonal dialects” evolved within and among populations of B. anynana and may therefore act as precursors of an ongoing speciation process.

Reproductive data of individual insects are extremely hard to collect under natural conditions, thus the study of research questions related to oviposition has not advanced. Patterns of oviposition are often inferred only indirectly, through monitoring of host infestation, whereas the influence of age structure and several other factors on oviposition remains unknown. Using a new approach, in this article, we live-trapped wild Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) females on the Greek island of Chios during two field seasons. For their remaining lifetime, these females were placed individually in small cages and their daily oviposition was monitored. Reproduction rates between cohorts from different collection dates were then compared. The results showed that in the different captive cohorts the average remaining lifetime and reproduction were highly variable within and between seasons. Multivariate regression analysis showed that the month of capture had a significant effect on captive life span, average daily reproduction, and patterns of egg laying. The effect of year was significant on reproduction, but not on captive life span. These differences between sampling periods probably reflect differences in the availability of hosts and other factors that vary during the season and affect age structure and reproduction. Using a non-parametric generalized additive model, we found a statistically significant correlation between the captive life span and the average daily reproduction. These findings and the experimental approach have several important implications.

Although the general concept of capital vs. income breeding has become widely used in insect ecology, finding easy-to-measure indices for quantifying the role of larval- vs. adult-derived nutrients in egg production has remained a challenge. When searching for possible candidates for this task, we evaluated the applicability of three morphometric ratios to be measured on freshly eclosed adults: (1) relative size of female abdomen, (2) sexual size dimorphism, and (3) proportion of volume of mature eggs relative to total volume of female abdomen. We report the values of these indices in five species of geometrid moths [Hypomecis punctinalis Scopoli, Ematurga atomaria L., Selenia tetralunaria Hufnagel, Semiothisa clathrata L., and Epirrhoe alternata Muller (all Lepidoptera: Geometridae)] and compare them to the degrees of income breeding measured directly by oviposition experiments. As a comparison, we also recorded the ovigeny index and the effect of income on lifespan. All morphometric indices varied considerably between the species studied, and, as predicted, the values of all three proposed indices were higher in the more capital-breeding species. The only exception to this pattern was a low proportion of mature eggs in abdomens in one primarily capital-breeding species, S. tetralunaria. Unlike other capital breeders, this species also proved to be largely synovigenic, indicating that capital breeding and pro-ovigeny are not strictly linked. The reproductive traits measured concord with ecological niches occupied by the species studied: the oligophagous meadow dwellers were largely income breeding and synovigenic, whereas the polyphagous forest dwellers were capital breeders. The high and predictable among-species variation in egg-production strategies suggests that geometrid moths form a promising target group for comparative studies on respective traits. Simple anatomical indices, in turn, appear to be applicable as easy-to-record proxies of egg production strategies.

The term 'puddling' includes feeding on (dried) mud and various excrements and secretions of vertebrates, and carrion. It is thought to be a form of supplementary feeding, not targeted at obtaining energy. Although the natural history of the puddling phenomenon in herbivorous arthropods becomes better known, it is still largely unclear how puddling (in particular for sodium) affects fitness despite the growing knowledge of insect physiology at the cellular level. If we follow the definition used for puddling in Lepidoptera, representatives of a wide range of herbivorous and detrivorous terrestrial arthropods (Lepidoptera, Orthoptera, Blattodea, Hymenoptera, Hemiptera, Diptera, and Diplopoda) have been observed to puddle. It appears that those species with diets low in sodium (e.g., folivorous larvae) puddle for sodium whereas those with diets low in nitrogen (e.g., detritivores) puddle for nitrogen. Sex differentials in puddling behavior can usually be explained by transfers of nutrients from males to females during mating. Puddling is rare or absent in immature stages and there is some evidence that nutrients from puddles increase female reproductive success. Strong evidence for the widely cited hypothesis that sodium from puddles is used to enhance neuromuscular activity is still lacking. High mobility and long life spans could be associated with puddling behavior, whereas insects that are concealed or well defended are less likely to puddle (e.g., beetles). The role that risks of pathogen and parasite infection as well as predation at puddling substrates may play in the evolution of puddling remains virtually unexplored.

Fruit-feeding butterflies are among the longest lived Lepidoptera. While the use of pollen-derived amino acids by Heliconius butterflies has been interpreted as important for the evolution of extended lifespans, very little is known about the life-history consequences of frugivory. This issue is addressed by investigating effects of four adult diets (sugar, sugar with amino acids, banana, and moistened banana) on lifespan and reproduction in the fruit-feeding butterfly Charaxes fulvescens Aurivillius (Lepidoptera: Nymphalidae). Female butterflies were collected from Kibale National Park, Uganda, and kept individually in cages near their natural habitat and data were collected on lifespan, oviposition, and hatching of eggs. Lifespan in captivity was longer for the sugar and the amino acid cohort, than for the banana cohorts. The longitudinal pattern of oviposition was erratic, with many days without oviposition and few periods with high numbers of eggs laid. Butterflies typically did not lay eggs during their 1st week in captivity and the length of the period between capture and first reproduction was significantly shorter for butterflies fed moistened banana. The length of the reproduction period (first reproduction–last reproduction in captivity) and the reproduction rate (total number of eggs/length of the reproduction period) did not differ significantly between the diet treatments. Those fed with amino acid and moistened banana had significantly higher egg hatchability than those fed with sugar and banana. We found no evidence for a lifespan cost of reproduction. Our results show that (1) female C. fulvescens can use amino acids in their diet for laying fertile eggs, (2) more wing-wear does correlate with lower survival in captivity (indicating aging in the wild), but not with intensity of reproduction (providing no evidence for reproductive aging), and (3) fruit-feeding butterflies may be dietary restricted in the field.

Reproductive tactics of males can change with individual quality, relat-edness and social structure. Here we describe the behaviours of malegrey-cheeked mangabeys towards other males, and females and theiroffspring (Lophocebus albigena) in relation to male status (high-rank-ing⁄low-ranking⁄transient) and group composition in Kibale NationalPark, Uganda. High-ranking males had the highest mating success, fre-quency of loud calls, mate guarding and aggression towards females andmales. Only transient males were often observed to be aggressivetowards juveniles, while some high-ranking males provided infant care.Mating tactics of high-ranking males varied greatly among the five stud-ied groups, probably as a function of the intensity of male–male compe-tition. These results are discussed with regard to the role of male–malecompetition and behaviours that could affect female mate choice as tac-tics to obtain reproductive success. Ethology Ethology 114 (2008) 851–862 a 2008 The AuthorsJournal compilation a 2008 Blackwell Verlag, Berlin

Many butterflies in tropical forests feed on fruits that have fallen to the forest floor. This substrate differs in many ways from floral nectar, and therefore fruit-feeding butterflies are expected to possess adaptations for efficient foraging, choice, and ingestion of their food. Differences in food quality and in spatial and temporal availability are also likely to have led to life history evolution. Here we describe the sugar and nitrogen content of fruits that butterflies feed on in at ropical forest in Uganda, and measure the attractiveness of these fruits to the local butterfly fauna together with the role that decay plays in the attraction. These data are supplemented with feeding observations at fruit falls in the forest. Our results show that (1) fruits contain significant and variable concentrations of sugar and nitrogen, and constitute a nutritious food source for butterflies in tropical forests; (2) fruit-feeding butterflies use cues from the fruits and fermentation products to locate their food; (3) different classes of fruit-feeding butterflies may vary in their preferences for certain fruits, and differ in their ability to find preferred food; an d( 4) fruit choice is not strongly correlated with attractiveness or nutrient content. The results are discussed in the light of the evolution of food searching and life history strategies.

Because tropical forests face serious threats and are usually situated in developing countries, cheap and easy Rapid Biodiversity Assessment (RBA) seems an ideal strategy for documenting changes in habitat quality and setting conservation priorities. Fruit-feeding butterflies are often used as focal taxa to document biodiversity trends in tropical forests. However, the choice of inappropriate sampling strategies may nullify its value. More extensive data sets that sample multiple months and seasons and incorporate the vertical dimension are needed as a baseline for designing reliable sampling regimes. Therefore, we performed a butterfly trapping study in Ghana, using both understorey and canopy traps, and sampling seven periods covering dry and wet seasons. Both individual numbers and species richness were on average three to four times higher in the understorey than in the canopy traps with strikingly different species composition (only 11% overlap in species). The number of species and individual abundance recorded in a month varied extensively. This study underlined the importance of taking into account temporal variation and vertical stratification when designing RBAs of fruit-feeding butterflies in West African forests. We recommend the use of both understorey and canopy traps and inclusion of both ‘wet’ and ‘dry’ seasons into RBA sampling regimes. Resume Comme les forets tropicales font face a des menaces graves et qu'elles sont en general situees dans des pays en developpement, une evaluation rapide de la biodiversite (RBA) semble une strategie ideale pour documenter les changements de qualite de l'habitat et etablir des priorites de conservation. On se sert souvent des papillons frugivores comme taxons focaux pour documenter les tendances de la biodiversite dans des forets tropicales. Cependant, le choix de strategies d’echantillonnage inappropriees risque d'annuler leur valeur. Il faut des ensembles de donnees plus complets, qui echantillonnent sur des mois et des saisons et qui integrent une dimension verticale pour etablir la base de reference permettant de concevoir des regimes d’echantillonnage fiables. C'est pourquoi nous avons fait une etude de piegeage des papillons au Ghana, en utilisant des pieges en sous-bois et dans la canopee, et en couvrant sept periodes comptant des saisons seches et des saisons des pluies. Aussi bien les chiffres individuels que la richesse en especes etaient en moyenne 3 a 4 fois superieurs dans les pieges places en sous-bois que dans la canopee, avec une composition des especes remarquablement differente (seulement 11% de recouvrement des especes). Le nombre d'especes et l'abondance individuelle enregistres en un mois variaient enormement. Cette etude souligne qu'il est important de prendre en compte la variation temporelle et la stratification verticale lorsque l'on prepare une RBA de papillons frugivores dans des forets d'Afrique de l'Ouest. Nous recommandons l'emploi de pieges en sous-bois et dans la canopee et l'inclusion de saisons « seches » et « humides » dans les regimes d’echantillonnages d'une RBA.

Temporal variation and phenology of tropical insect communities and the role of environmental factors controlling this variation is poorly understood. A better understanding is needed, for example, to predict the effects of climate change on tropical insect communities and to assess the long-term persistence of tropical communities. We studied seasonal and inter-annual variation in tropical fruit-feeding butterflies by exploiting a unique 137-month abundance time series of >100 species, sampled at 22 locations in the medium altitude montane rain forest of Kibale National Park, western Uganda. Precipitation peaked twice per year, about 20 d after each equinox. Vegetation greenness peaked approximately 33 d later. Species richness and abundance of butterflies peaked about 2 and 3 months, respectively, after the greenness peak. Furthermore, temporal shifts in peaks of butterfly abundances of each 6-month cycle positively correlated with temporal shifts in peaks of vegetation greenness approximately three months before. The butterfly assemblages of ENSO warm phase years differed significantly from assemblages of the other years. To our knowledge this is the first elucidation of bi-annual rhythms in butterfly assemblages. Host plant availability could explain the seasonal cycles in butterfly abundance and species richness, because the 3-month lag observed matches with the egg-to-adult development time in the studied species.