Showing papers on "Lasius published in 2016"

Highly specific responses to queen pheromone in three Lasius ant species

Abstract: Queen pheromones mediate the reproductive division of labor in social insect colonies and provide novel opportunities for investigating the evolution of animal communication. Previous work found that queens in the ant genus Lasius produce several 3-methylalkanes in greater relative amounts than workers do. At least one of these (3-MeC31) is a queen pheromone that regulates worker sterility in two Lasius species, although there are indications that other 3-methylalkanes might also function as queen pheromones. Here, we presented workers from three Lasius species with four different 3-methylalkanes, and measured the effect on worker ovary development. In all three species, only 3-MeC31 showed clear evidence of inhibiting worker fecundity. Our results suggest that worker ants can discriminate homologous hydrocarbons that differ in chain length and only treat specific homologs as queen pheromones. These results provide insight into the conflicting selective pressures on cuticular hydrocarbons arising from their multiple roles in signaling and adaptation to the abiotic environment.

The Westpalaearctic Lasius paralienus complex (Hymenoptera: Formicidae) contains three species.

Abstract: Application of Numeric Morphology-Based Alpha-Taxonomy (NUMOBAT) demonstrated the existence of three cryptic species within the Westpalaearctic Lasius paralienus species complex: L. paralienus Seifert, 1992, having a wider European distribution north to Sweden, L. casevitzi sp. nov., an endemic of Corsica, and Lasius bombycina sp. nov. from southeast Central Europe, the Balkans and Asia Minor. Hierarchical NC-Ward clustering and non-hierarchical NC-k-means clustering of 16 morphological characters resulted in 98.7% identical classifications within 76 examined nest samples of the three species. The classification error in 180 worker individuals was 0% in a linear discriminant analysis (LDA) and 1.3% in a LOOCV-LDA. Differential characters to other species groups and an identification key of the six European members of the Lasius alienus Forster species group are provided.

Queen pheromones modulate DNA methyltransferase activity in bee and ant workers.

Abstract: DNA methylation is emerging as an important regulator of polyphenism in the social insects. Research has concentrated on differences in methylation between queens and workers, though we hypothesized that methylation is involved in mediating other flexible phenotypes, including pheromone-dependent changes in worker behaviour and physiology. Here, we find that exposure to queen pheromone affects the expression of two DNA methyltransferase genes in Apis mellifera honeybees and in two species of Lasius ants, but not in Bombus terrestris bumblebees. These results suggest that queen pheromones influence the worker methylome, pointing to a novel proximate mechanism for these key social signals.

A sublethal imidacloprid concentration alters foraging and competition behaviour of ants

Abstract: Neonicotinoid pesticides, such as the widely used compound imidacloprid, are suspected to impair cognitive capacity, behaviour, and fitness of a number of non-target species. We tested whether sublethal imidacloprid concentrations alter the foraging and aggression behaviour of two European ant species. Even though the nestmate-recruitment of Lasius niger was not affected by pesticide exposure, these ants required more time to become active and the number of foraging workers was lower than in sub-colonies not exposed to imidacloprid. In interspecific confrontations, imidacloprid increased the aggressiveness of a usually subordinate species (Lasius flavus) enormously (3.7-fold increase in average number of aggressive encounters), whereas they did not affect a subdominant species (L. niger) that severely (1.2-fold increase in average number of aggressive encounters). The high frequency of aggressive encounters of L. flavus vs. non-exposed L. niger workers, reduced their survival probability significantly down to 60 %. The observed behavioural alterations of the two ant species have the potential to impair their viability and co-occurrence with behaviourally dominate species due to a decreased exploitative competition and a reduced chance to locate and use resources before competitors. As competition is considered key in structuring ant communities, changes in aggressiveness are likely to alter established dominance hierarchies and thereby the dynamic and structure of ant communities.

The importance of ants in cave ecology, with new records and behavioral observations of ants in Arizona caves

Abstract: The importance of ants as elements in cave ecology has been mostly unrecognized. A global list of ant species recorded from caves, compiled from a review of existing literature, is presented. This paper also reviews what is currently known about ants occurring in Arizona (USA) caves. The diversity and distribution represented in these records suggests ants are relatively common cave visitors (trogloxenes). A general utilization of caves by ants within both temperate and tropical latitudes may be inferred from this combined evidence. Observations of ant behavior in Arizona caves demonstrate a low level and sporadic, but persistent, use of these habitats and their contained resources by individual ant colonies. Documentation of Neivamyrmex (N. nyensis) preying on cave-inhabiting arthropods is reported here for the first time. Observations of hypogeic army ants in caves suggests they may not penetrate to great vertical depth in search of prey, but can be persistent occupants in relatively shallow, horizontal sections of caves where they may prey on endemic cave animals. First cave records for ten ant species are reported from Arizona caves. These include two species of Neivamyrmex (N. nigrescens Cresson, N. nyensis Watkins; Formicidae: Dorylinae), four myrmicines (Pheidole portalensis Wilson, Pheidole cf. porcula Wheeler, Solenopsis aurea Wheeler and Stenamma sp. Westwood), one dolichoderine (Forelius keiferi Wheeler) and three formicines (Lasius arizonicus Wheeler, L. sitiens Wilson, and Camponotus sp. Mayr).

Biological activity of the enantiomers of 3-methylhentriacontane, a queen pheromone of the ant Lasius niger

Abstract: Queen pheromones are essential for regulation of the reproductive division of labor in eusocial insect species. Although only the queen is able to lay fertilized eggs and produce females, in some cases workers may develop their ovaries and lay male-destined eggs, thus reducing the overall colony efficiency. As long as the queen is healthy, it is usually in the workers' collective interest to work for the colony and remain sterile. Queens signal their fertility via pheromones, which may have a primer effect, affecting the physiology of workers, or a releaser effect, influencing worker behavior. The queen pheromone of the ant Lasius niger was among the first queen pheromones of social insects to be identified. Its major component is 3-methylhentriacontane (3-MeC31), which is present in relatively large amounts on the queen's cuticle and on her eggs. 3-MeC31 regulates worker reproduction by inhibiting ovarian development. Most monomethyl-branched hydrocarbons can exist in two stereoisomeric forms. The correct stereochemistry is fundamental to the activity of most bioactive molecules, but this has rarely been investigated for methyl-branched hydrocarbons. Here, we tested the bioactivity of the (S)- and (R)-enantiomers of 3-MeC31, and found that whereas both enantiomers were effective in suppressing worker ovarian development, (S)-3-MeC31 appeared to be more effective at suppressing aggressive behavior by workers. This suggests that the natural pheromone may be a mixture of the two enantiomers. The enantiomeric ratio produced by queens remains unknown because of the small amounts of the compound available from each queen.

Vegetation heterogeneity caused by an ecosystem engineer drives oviposition-site selection of a threatened grassland insect

Abstract: Soil-disturbing ecosystem engineers play an important role in plant-species diversity in grasslands as they increase vegetation heterogeneity by creating gaps due to burrowing or mound-building activities. However, knowledge of the ecological importance of these microsites for arthropods is still rare. In this study, we analyse the role of ant-nest mounds of the yellow meadow ant (Lasius flavus) for oviposition-site selection of the silver-spotted skipper (Hesperia comma). Ant mounds were searched for H. comma eggs. Microclimatic and vegetation parameters were ascertained at occupied sites and control sites within the matrix vegetation. Furthermore, we analysed the habitat requirements of L. flavus by means of nest counting and the sampling of environmental parameters within different sites. L. flavus occurred most frequently in abandoned and less steep sites with deeper soils. Mean egg occupancy rates of H. comma on ant hills were 32 %, nearly twice as high as at control sites (18 %). In contrast to the surrounding vegetation, nest mounds were characterized by a lower vegetation cover and litter and a higher proportion of bare ground. Furthermore, they had a higher cover of host plants compared with control samples. These microhabitats offered the following essential key factors for the larval development of H. comma: (1) a suitable microclimate due to open vegetation and (2) a high amount of host plants. This study highlights the importance of L. flavus as an ecosystem engineer within central European grasslands because this species increases vegetation heterogeneity.

The importance of diurnal and nocturnal activity and interspecific interactions for space use by ants in clear-cuts.

Abstract: 1. Full sunlight conditions in open clear-cuts may limit the activity of ants as soil surface temperatures reach lethal levels. Therefore, differences may be expected between the diurnal and nocturnal activity of ants, and in the interactions between ant species. These predictions, however, have been poorly investigated so far. 2. The circadian activity of ants in clear-cuts in managed forests in Poland was investigated. Repeated counts of ants were performed during the day and the following night at the clear-cut edge and in the clear-cut interior. Interspecific interactions and the effect of plant coverage were also considered. 3. Abundances of Formica fusca Linnaeus and red wood ants were higher during the day, whereas Myrmica were more common at night. Formica fusca, Lasius and red wood ants were more common at the clear-cut edge than in the interior. Myrmica showed the opposite pattern, but at night, its numbers increased at the edge. Plant coverage positively affected F. fusca and red wood ants. 4. Red wood ants tended to be negatively associated with Lasius, whereas they were neutral for F. fusca. The negative association of red wood ants and Myrmica was stronger during the day compared to night. 5. The time of day was a strong driver of ant activity in the clear-cuts, whereas the distribution of red wood ants was of lesser importance. It is concluded that circadian activity may substantially contribute to niche separation between coexisting species, therefore, studies performed exclusively during the day cannot reflect the real structure of the community.

Analysis of Insect toxicity and repellent activity of Phytochemicals from "Skimmia laureola, Nair" against "Black garden ant, Lasius niger" of Pakistan.

Abstract: A study was conducted to evaluate the toxicity and repellency of essential oils from root, stem and leaves of Nazar panra, Skimmia laureola (DC.) Zucc. Ex Walp. of family (Sapindales: Rutaceae) ver. Nair of Pakistan. The oils were tested at three concentrations i.e. 1, 5 and 10%. Black garden ant, Lasius niger L. (Hymenoptera: Formicidae) of Pakistan were selected and exposed to essential oils at room temperature. All essential oils showed Insecticidal activity with LC(50)=10.15, while dose dependant effect was significant with R(2)=0.98. It can be concluded that the three Essential oils in this study have both Insecticidal as well as repellent effect.

Ant-fungus interactions : laboulbenia camponoti batra in Italy and a new host for L. formicarum thaxter (Fungi: Ascomycota, Laboulbeniales)

Abstract: One Laboulbenia species is added to the checklist of Italian fungi Laboulbenia camponoti was detected on the ant Camponotus aethiops Additionally, L formicarum was found on a new host (Lasius niger) in France An updated map of world distribution for the two Laboulbenia is presented Based on present knowledge, L camponoti shows a much higher structural and phylogenetic host specificity than L formicarum

Host plant preference in the protected myrmecophilous Transylvanian Blue ( Pseudophilotes bavius hungarica ) butterfly (Lepidoptera: Lycaenidae) and its relationship with potential ant partners

Abstract: When selecting specific host plants, caterpillars of many lycaenid butterflies, such as the protected Pseudophilotes bavius hungarica, are known to engage in various interactions with ants, which help them survive. Although P. bavius is a protected species, data about its host plant selection is very scarce, and little information is available on its myrmecophilous relationships. Our aim was to identify the host plant characteristics that determine the occurrence of the caterpillar and to clarify the specificity of its myrmecophily. We conducted a series of field surveys regarding host plant characteristics. Laboratory experiments were carried out to investigate the nature of interactions between the caterpillar and its potential ant partners. Control experiments involving non-visiting ants were also performed. On the basis of our findings, the physical characteristics of host plants do not seem to influence host plant choice, but the absence of aphids and the presence of different ant species proved important. According to the results of behavioural assays, neutral reactions to the caterpillars were recorded in the case of ant species that regularly visited the host plant (Lasius paralienus, Camponotus aethiops), in contrast to Tapinoma subboreale, which was not observed at all on the host plants and which behaved aggressively towards the larvae. Therefore, the caterpillar is expected to show a certain ant host selectivity. The study constitutes an essential contribution to our knowledge of the natural history of a protected butterfly species, which can be used as a basis for more appropriate management strategies, while also shedding light on aspects of myrmecophilous relationships in Lycaenidae in general.

High Survival of Lasius niger during Summer Flooding in a European Grassland

Abstract: Climate change is projected to increase the frequency of extreme events, such as flooding and droughts, which are anticipated to have negative effects on the biodiversity of primary producers and consequently the associated consumer communities. Here we assessed the effects of an extreme early summer flooding event in 2013 on ant colonies along an experimental gradient of plant species richness in a temperate grassland. We tested the effects of flood duration, plant species richness, plant cover, soil temperature, and soil porosity on ant occurrence and abundance. We found that the ant community was dominated by Lasius niger, whose presence and abundance after the flood was not significantly affected by any of the tested variables, including plant species richness. We found the same level of occupation by L. niger at the field site after the flood (surveyed in 2013) as before the flood (surveyed in 2006). Thus, there were no negative effects of the flood on the presence of L. niger in the plots. We can exclude recolonisation as a possible explanation of ant presence in the field site due to the short time period between the end of the flood and survey as well as to the absence of a spatial pattern in the occupancy data. Thus, the omnipresence of this dominant ant species 1 month after the flood indicates that the colonies were able to survive a 3-week summer flood. The observed ant species proved to be flood resistant despite experiencing such extreme climatic events very rarely.

Host ant use of the Alcon blue butterfly at the northern range margin

Abstract: In myrmecophilous insects, interactions with ants are often a key factor determining persistence of their populations. Regional variation in host ant use is therefore an essential aspect to consider to provide adequate conservation practices for such species. In this study, we examined this important facet of species’ ecology in an endangered myrmecophilous butterfly Phengaris (=Maculinea) alcon (Lepidoptera, Lycaenidae). The investigations conducted in peripheral populations in Estonia allowed us to expand the knowledge of its host ant use to the northern distribution limit of the species. Our data indicate that in its northernmost populations, the xerophilous ecotype of Phengaris alcon is primarily parasitizing a single host ant species, Myrmica schencki. The data collected are in line with the emerging evidence suggesting that peripheral and core populations of P. alcon use different host ants, and peripheral populations tend to display higher host ant specificity. We also show that, at its northern range margin, P. alcon might be more limited by the availability of its sole larval food plant in the region, Gentiana cruciata, than the densities of its host ant. Finally, we found a strong negative correlation between Myrmica spp. and Lasius spp. colony densities, suggesting that interspecific competition between ants could have a substantial influence on host ant availability of Phengaris butterflies, and thus should be taken into account in conservation plans of these species.

Behavioural development, fat reserves and their association with productivity in Lasius flavus founding queens

Abstract: Reproduction-related behaviours are key components determining individual fitness. Many behavioural traits are linked, and such trait associations often affect fitness. Here, we combine behavioural and physiological data during two critical time points of founding queens (early and late nest-founding stage) in the claustral ant Lasius flavus to assess how these factors affect their initial productivity. We show that most behavioural traits, except brood care behaviour, are plastic during queen development and demonstrate that there are alternative behavioural pathways to achieve high productivity under standardised conditions. These results indicate that queens can utilise multiple behavioural trait combinations to maximise reproductive output at the earliest, and arguably most critical, time of colony foundation.

Body Size in Males of the Ant Lasius niger (Hymenoptera: Formicidae) Along a Metal Pollution Gradient.

Abstract: Environmental stress can lead to a decrease in the body size of insects. As social insects, ants have a complex caste system; each caste has its own morphological traits and functions in the colony, hence the effects of stress may manifest differentially among different ant castes. Here we investigated the body size of males of the common garden ant, Lasius niger L., 1758, living in a postmining area polluted mainly by Zn, Cd, and Pb. We examined if individual body size decreases with the pollution gradient. The ants were sampled from 39 wild colonies originating from 17 sites located along the metal pollution gradient; head width was used as the estimator of body size. We failed to show a significant correlation between pollution and male body size, indicating no direct effect of pollution on the body size of males of the investigated ant. However, we found a significant dependence with the colony of origin, which is in line with a previous study performed on this species in unpolluted sites. These results further strengthen a general conclusion that morphological traits in ants, such as body size or fluctuating asymmetry, are relatively invariable and stable across gradients of metal pollution.

The plant ecology of ant-hills in calcareous grasslands

Abstract: SUMMARY (1) The vegetation on 206 Lasius flavus ant-hills of a wide range of size and ant activity, and in 103 pasture quadrats, was sampled on a 0-6-ha chalk grassland plot at Beacon Hill, Aston Rowant National Nature Reserve, Oxfordshire in 1969. (2) Maps of each species over the plot showed that many species were only likely to occur on an ant-hill if they were present in the vegetation near the mound. In the case of twenty-four of the thirty-five species tested, there was a significant association at the 5% level between their presence on ant-hills and their occurrence in surrounding vegetation quadrats 0 3 m away. The association tended to be stronger for those species with efficient vegetative reproduction than for the species which reproduce only by seed. (3) The abundance of each species on ant-hills was considered in relation to the intensity of soil heaping and ant-hill volume. Young mounds smother existing vegetation and are invaded by Carex flacca, Festuca rubra, Helianthemum chamaecistus, Leontodon hispidus and Lotus corniculatus. As they grow larger, rosettes of Carex flacca, Hieracium pilosella, Leontodon hispidus and Plantago lanceolata become more frequent around the edges of the mounds as they are killed on the tops by soil heaped by the ants. Thymus drucei and Helianthemum chamaecistus spread to make up a high proportion of the total percentage cover on most large mounds. It seems that if the ant colonies survive, ant-hills can persist in this state, with a stable vegetation, certainly for tens and probably for hundreds of years. (4) The ant colonies frequently disappear from small mounds. The chambers and channels in the soil disappear, organic matter accumulates, an Ao horizon is formed, the structural aggregates increase in size, and soil heaping ceases. Carexflacca, Leontodon hispidus, Plantago lanceolata and in particular, Hieracium pilosella become established over the whole surface and the vegetation becomes closed. (5) When grazing ceases, the tall growth of grasses may eliminate low-growing species like Thymus drucei from ant-hills and the surrounding vegetation. When Festuca rubra is the dominant grass the ant colonies survive, but when Arrhenatherum elatius, Brachypodium pinnatum, B. sylvaticum, Helictotrichon pratense, H. pubescens or Zerna erecta invade the mounds the ant colonies ultimately become extinct.

No effect of Zn-pollution on the energy content in the black garden ant.

Abstract: Social insects may display a response to environmental pollution at the colony level. The key trait of an ant colony is to share energy between castes in order to maintain the existing adult population and to feed the brood. In the present study we calorimetrically measured the energy content per body mass (J/mg) of adults and pupae of workers, males and females of the black garden ant Lasius niger. The ants were sampled from 37 wild colonies originating from 19 sites located along the metal pollution gradient established in a post-mining area in Poland. The cost of metal detoxification seen as a possible reduction in energy content with increasing pollution was found neither for pupae nor adults. However, a considerable part of variance in energy content is explained by belonging to the same colony. These findings stress the importance of colony-specific factors and/or the interaction of these factors with specific site in shaping the response of ants to metal-pollution stress. Colony-related factors may constrain possible selfish decisions of workers over energy allocation in workers and sexual castes.

STIMULI RELEASING DIGGING BEHAVIOR IN THE WESTERN HARVESTER ANT1 ( Hymenoptera : Formicidae )

Abstract: The western harvester ant, Pogonomyrmex occidentals, can locate and excavate workers buried in sand. Ants dug to any large part of a worker's body, and to ant larvae and pupae, but more slowly than to intact adults. Digging was oriented by odors detected by the antennae. The odors passed through waxed paper, but not through Saran wrap. Workers of the western harvester ant, Pogonomyrmex occidentalis (Cresson), can detect a buried worker and will dig through con siderable sand in attempting to free the ant. This paper discusses certain factors that are involved in such detection and digging. Belt (1874) reported the "rescue" of Eciton hamatum workers that he trapped under stones or in balls of clay near their trails. Lafleur (1940) trapped Formica subservicea and Lasius workers in clay pellets and returned them to the nests. Other workers promptly freed the trapped ants while paying little attention to similar pellets not containing trapped ants. Wheeler (1910: 537) noted that workers of a large laboratory colony of Neivamyrmex nigrescens repeatedly fell into the water of a moat surrounding the colony. On several oc casions, he saw other workers reach in and pull them out. Forrest (1963) studied the digging behavior of four species of Acanthomyops and of Lasius flavus nearcticus under standardized con ditions. She reported that when a worker was trapped in compact earth in a nest, other workers approached it, dug earth from around it, pulled it out, dragged it a little distance away, and cleaned it. Some workers usually continued digging and burrowing at the site after the ant was freed. Workers also dug to free ants of other species, but attacked them after they had released them. Digging out a trapped worker was much more prompt, vigorous, and sustained, and engaged more workers than did digging at a control site. She also severed various parts of ants in an effort to localize an origin of the means of

Patterns of distribution, human-mediated dispersal and intraspecific variations in urbanized landscapes : how ants respond to urbanization

Abstract: Urbanization is a complex process involving simultaneous changes in several environmental conditions, including ground and air temperature (urban heat island effect), habitat fragmentation and chemical pollution. These changes are often associated with biodiversity loss and changes in ecosystems functioning. However, more than a sink for biodiversity, urban areas constitute true ecosystems where many native and alien species survive and even grow stable populations. The “urban ecosystem” is now considered as an important element in the functioning of densely populated environments, in human health and well-being, as well as in biodiversity conservation. More fundamentally, urbanization constitutes “real life experiment” offering ecologists an opportunity to better understand ecological and evolutionary processes over fine spatial and temporal scale. This thesis investigates ecological and evolutionary consequences urbanization at different biological organization levels using ants (Formicidae) as biological models. First, at the biological community level, we showed that native and alien ant responses to urbanization were species-specific as each species was affected by its own set of environmental changes associated with urbanization (e.g., fragmentation, ground temperature) and climate. Second, we explored the little studied process of human-mediated dispersal by (i) proposing a novel theoretical framework focusing on human activities rather than directly on species and (ii) developing an innovative simulation model of dispersal by transport in terrestrial landscapes, MoRIS (Model of Routes of Invasive Spread). Third, we investigated how urbanization affected novel biotic interactions between an alien ant species (Lasius neglectus), an alien ectoparasite fungus (Laboulbenia formicarum) and native ant species. We showed that urbanization impacted the size of L. neglectus colonies, which were smaller in urban area, as well as L. formicarum prevalence on L. neglectus, which was higher in urban areas. Finally, we investigated intraspecific variations between urban and rural conspecifics of an urban tolerant species: Lasius niger. We found that urban young queens were smaller and lighter, less stressed by high temperature and performed multiple mating more often than rural young queens. In common garden, colony founding success were globally similar but urban incipient colonies produced significantly less pupae (and consequently workers). We also found that workers produced in common garden experiments were more variable in size (higher head width variance in both inter- and intra-colony) in urban colonies than in rural colonies. No evidence for genetic differentiation between urban and rural populations was found, suggesting that gene flow was not disrupted between urban and rural populations. All our results converge to a renewed vision of ecological and potential evolutionary dynamics occurring in urban environments. Further investigation will be necessary to assess how ecological processes influence evolutionary trajectories in urban ecosystems, using both ecological (e.g. ant densities and abundances along the urban gradient) and genomic approaches (e.g. using “genotyping by sequencing” methods to identify genes responsible for adaptation to urbanization)

Behavior Analysis of Ants from Video Sequences

Abstract: The movement of small animals in well-defined environments is increasingly studied in many areas; including ecotoxicology, learning, and behavioural ecology. Here we de- scribe an algorithm designed to analyze individual foraging ants from a colony of Lasius niger. The inputs to the algorithm were images from a video sequence. The algorithm performed a series of pre-processing steps to identify the ants from the pixels, measurements were extracted and individual ants were tracked in time. The location of the ants in position and time were recorded as heat maps denoting the favorite locations of the ants. The ants were videoed in a foraging experiment on a T-maze a single trail bifurcation.

Pheidole pallidula como posible vector de polinización asistida en cultivos de calabacín (Cucurbita pepo L.)

Abstract: Zucchini protected crops are increasing their relecance in the agricultural sector However, the cultivation of this vegetable has a problem associated with pollination, attributed to the lack of pollinators, wich makes a much less productive crops To date, farmers use fithormones that inducing the fruit, but consumers reject these methods, since this prodfuct remains in the fruit even when it is on the market This study attempts to evaluate the ant species Pheidole pallidula (Nylander, 1849) as a possible vector of pollination in crops of zucchini, to avoid the use of more costly and/or less environmentally friendly techniques This requires a count of pollen grains carrying the outgoing ants of male flowers and the incoming ants of the female flower This count is performed over a period of time of 5 minutes In addition, ot conducted an exclusion experiment on three groups of plants (G1: Plants with Ppallidula, G2: Plants with Lasius niger (linnaeus, 1758) and G3

Antropogenic influence on myrmecofauna on the technological-transformed environs OJSC «Naftokhimik Carpathians»

Abstract: The human impact on myrmecofauna on the technologically-transformed neighborhoods OJSC «Naftokhimik Carpathians» were analyzed. Under the influence of industrial gaseous emissions significantly reduced the density of the ant’s nests genus Formica Linnaeus, 1758, marked their replacement ants genera Lasius Fabricius, 1804 and Myrmica Latreille, 1804. Most resistant to anthropogenic pressure is L. niger L. and M. rubra L., are found in all disturbed coenoses; thus, L. niger L. stands dominant, and M. rubra L.- subdominant density of the nests. In the most contaminated zone (area 0) are found only L. niger L. and M. rubra L. At reduction degree of influence of the industrial emissions, but increasing degree of the recreation (section 1.5 km) marked as 2 species of the ants, observed the disappearance of M. rubra L. and appearance of the nests of M. ruginodis Nylander. If the distance from the source of pollution to 5 miles ant species composition increases to 6 species, appear T. caespitum L., L. flavus Fabricius and F. cunicularia Latr. Thus there is predominance of nests L. niger L., located mainly under stones. At the maximum distance from the source of pollutants (at a distance of about 10 km) recorded a slight decrease in species composition (5 species). At the control plot, located in the territory of Nadvirnianskiy forest, we found 11 species of ants: C. herculeanus Forel, F. cunicularia Latr., F. fusca L., F. polyctena Foerster, F. pratensis Retzius, F. rufa L., L. flavus Fabr., L. niger L., M. rubra L., M. ruginodis Nyl. and T. caespitum L.

Famished foragers suffer malnutrition faster than fat workers

Abstract: ![Figure][1] Black garden ants ( Lasius niger ) on a cotton bridge. Photo credit: Audrey Dussutour. Every family has a picky eater, but imagine feeding a family of 20,000, where some siblings eat nothing but pasta and others expect steak. This is the situation faced by forager ants on a