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The present study is the first qualitative and quantitative analysis of the diet of Algerian hedgehogs (Atelerix algirus) in Kabylia, Algeria. The study was carried out between May and October 2014 and covered two different sites, Yakouren (a forested site) and Tizi- Rached (an agricultural site). In Yakouren, the analysis of droppings allowed us to identify 12,050 items grouped into 16 categories of eaten preys, while in Tizi-Rached, 13,543 items grouped into 13 categories of preys were identified. In both locations, the Hymenoptera category is the most eaten type of prey at a rate of 93% in Yakouren and 98% in Tizi-Rached. Moreover, the seasonal variation, the food selectivity, and comparative studies of the consumed categories between the two sites were analyzed in this study. In the Hymenoptera category, 99% of the consumed preys at both sites belonged to the family Formicidae. A deeper investigation revealed that 13 species were in that family in Yakouren and 11 species in Tizi-Rached. The species most consumed by the hedgehogs at both sites are Messor spp. at a rate of 49% in Yakouren and 91% in Tizi-Rached. In order to analyze the preference for some prey, a biochemical analysis of the energy intake was performed and discussed. [ABSTRACT FROM AUTHOR]

In insect societies, chemical communication plays an important role in colony reproduction and individual social status. Many studies have indicated that cuticular hydrocarbons (CHCs) are the main chemical compounds encoding reproductive status. However, these studies have largely focused on queenless or monogynous species whose workers are capable of egg laying and have mainly explored the mechanisms underlying queen-worker or worker-worker reproductive conflicts. Less is known about what occurs in highly polygynous ant species with permanently sterile workers. Here, we used the Argentine ant as a model to examine the role of CHCs in communicating reproductive information in such insect societies. The Argentine ant is unicolonial, highly polygynous, and polydomous. We identified several CHCs whose presence and levels were correlated with queen age, reproductive status, and fertility. Our results also provide new insights into queen executions in the Argentine ant, a distinctive feature displayed by this species in its introduced range. Each spring, just before new sexuals appear, workers eliminate up to 90% of the mated queens in their colonies. We discovered that queens that survived execution had different CHC profiles from queens present before and during execution. More specifically, levels of some CHCs were higher in the survivors, suggesting that workers could eliminate queens based on their chemical profiles. In addition, queen CHC profiles differed based on season and species range (native vs. introduced). Overall, the results of this study provide new evidence that CHCs serve as queen signals and do more than just regulate worker reproduction. [ABSTRACT FROM AUTHOR]

Dispersal has consequences not only for individual fitness, but also for population dynamics, population genetics and species distribution. Social Hymenoptera show two contrasting colony reproductive strategies, dependent and independent colony foundation modes, and these are often associated to the population structures derived from inter and intra-population gene flow processes conditioned by alternative dispersal strategies. Here we employ microsatellite and mitochondrial markers to investigate the population and social genetic structure and dispersal patterns in the ant Cataglyphis emmae at both, local and regional scales. We find that C. emmae is monogynous and polyandrous. Lack of detection of any population viscosity and population structure with nuclear markers at the local scale suggests efficient dispersal, in agreement with a lack of inbreeding. Contrasting demographic differences before and during the mating seasons suggest that C. emmae workers raise sexuals in peripheric nest chambers to reduce intracolonial conflicts. The high genetic differentiation recovered from the mtDNA haplotypes, together with the significant correlation of such to geographic distance, and presence of new nuclear alleles between areas (valleys) suggest long-term historical isolation between these regions, indicative of limited dispersal at the regional scale. Our findings on the ecological, social and population structure of this species increases our understanding of the patterns and processes involved under independent colony foundation. [ABSTRACT FROM AUTHOR]

Spatio-temporal variations in the composition of the animal interactive assemblages may result in variations in selective pressures on the plants. In ant–seed dispersal mutualisms, the study of the magnitude of spatial and temporal variation of ant assemblages is rarely studied, limiting inferences and generalizations on the evolution of this mutualism. Here, we describe the ant–disperser assemblage of the myrmecochorous herb Helleborus foetidus in 14 populations across the Iberian Peninsula, and dissect the variation in the assemblage into spatial and temporal components as a first step to evaluate the evolutionary potential of this interaction. The ant–visitor assemblage of H. foetidus was mainly represented by species of Formicinae and it was highly diverse and variable in composition and function. Ants behaving as legitimate dispersers and those with mixed behaviour numerically dominated the assemblage compared with elaiosome consumers. The magnitude of the spatial variation was higher than the temporal variation, suggesting that the relative frequency of each functional group will be more foreseeable among years in each population than among populations. At the expense of further analysis of the effects of such variation on dispersal success, we can envisage a selection mosaic scenario, where local adaptive responses of plants might arise as a result of local variations in the specific composition and function of the assemblage. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society, 2007, 92, 135–150. [ABSTRACT FROM AUTHOR]

In insects, cuticular hydrocarbon (CHC) profiles are complex phenotypic traits with several functions: they provide protection against pathogens and water loss and convey information about insect identity. They are particularly important in ants as they are the basis for colony-specific signatures, which allow nestmate recognition and thus help colonies protect their resources from competitors. Several studies have shown that levels of n-alkanes are strongly influenced by the environment and that, alongside methyl-branched alkanes, n-alkanes are involved in various signalling tasks. Here, we analysed the CHCs of the ant Aphaenogaster iberica along an elevational gradient running from sea level to 2000 m. Across this gradient, we found a considerable difference in mean daily temperature of more than 10 °C between the populations on either end of the gradient as well as a marked degree of genetic structuring among populations. Moreover, genetic distance between populations increased with elevational distance but was independent of horizontal distance. Low-elevation populations had larger amounts of heavier compounds, including nonacosane (C29), and smaller amounts of lighter compounds, including hexacosane (C26) and heptacosane (C27). The level of aggression among non-nestmates increased with elevational distance, horizontal distance and CHC dissimilarity. However, mean within-population aggression (i.e. among colonies of the same population) did not differ across elevation. We also found that aggression was related to CHC levels: the correlation between the level of aggression and CHC dissimilarity remained significant even after we accounted for the correlation between genetic distance and aggression. We propose that climatic differences at different elevations may constrain CHC diversity and, consequently, the process of nestmate recognition. • Cuticular hydrocarbons (CHCs) help ants protect themselves and communicate. • Levels of n -alkane are strongly influenced by the environment. • Variation of CHCs with elevation has consequences for nestmate recognition. • Global warming may impact ant behaviour through pleiotropic traits like CHCs. [ABSTRACT FROM AUTHOR]

Dispersal has consequences not only for individual fitness, but also for population dynamics, population genetics and species distribution. Social Hymenoptera show two contrasting colony reproductive strategies, dependent and independent colony foundation modes, and these are often associated to the population structures derived from inter and intra-population gene flow processes conditioned by alternative dispersal strategies. Here we employ microsatellite and mitochondrial markers to investigate the population and social genetic structure and dispersal patterns in the ant Cataglyphis emmae at both, local and regional scales. We find that C. emmae is monogynous and polyandrous. Lack of detection of any population viscosity and population structure with nuclear markers at the local scale suggests efficient dispersal, in agreement with a lack of inbreeding. Contrasting demographic differences before and during the mating seasons suggest that C. emmae workers raise sexuals in peripheric nest chambers to reduce intracolonial conflicts. The high genetic differentiation recovered from the mtDNA haplotypes, together with the significant correlation of such to geographic distance, and presence of new nuclear alleles between areas (valleys) suggest long-term historical isolation between these regions, indicative of limited dispersal at the regional scale. Our findings on the ecological, social and population structure of this species increases our understanding of the patterns and processes involved under independent colony foundation. [ABSTRACT FROM AUTHOR]