Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| a preliminary study of forensic entomology in medellín, colombia. | this is the first report of an ongoing study of insect succession on carrion carried out in medellín, colombia, using pigs (sus scrofa) as a model to determine the insect sequence over 207 days. during this period, 2314 insects belonging to the following orders and families were collected: diptera: calliphoridae, muscidae, piophilidae, sarcophagidae, syrphidae, otitidae; hymenoptera: apidae, formicidae, halictidae, mutilidae, vespidae; coleoptera: staphylinidae, histeridae, carabidae, scarabaeid ... | 2001 | 11457610 |
| ant odometry in the third dimension. | desert ants (cataglyphis) are renowned for their ability to perform large-scale foraging excursions and then return to the nest by path integration. they do so by integrating courses steered and the distances travelled into a continually updated home vector. whereas the angular orientation is based on skylight cues, how the ants gauge the distances travelled has remained largely unclear. furthermore, almost all studies on path integration in cataglyphis, as well as in spiders, rodents, and human ... | 2001 | 11459057 |
| mandibular gland chemistry of grass-cutting ants: species, caste, and colony variation. | the compositions of the alarm pheromones of two species of grass-cutting ant, atta bisphaerica and a. capiguara, were examined, and caste and colony variations quantified. the pheromones of a. bisphaerica and a. capiguara were remarkably similar and were composed of a complex mixture of volatiles in which 4-methyl-3-heptanone and 2-heptanone were the most abundant compounds. small but consistent intraspecific differences were found between the worker castes and between individual colonies. the r ... | 2001 | 11382057 |
| investigation of different combinations of derivatization, separation methods and electrospray ionization mass spectrometry for standard oligosaccharides and glycans from ovalbumin. | derivatization procedures using 1-phenyl-3-methyl-5-pyrazolone (pmp) and 2-aminonaphthalene trisulfone (ants) were selected among a number of well known methods for labelling carbohydrates. pmp derivatives were selected owing to our laboratory's previous high-performance liquid chromatography/electrospray ionization mass spectrometry (hplc/esi-ms) experience with these, whereas the ants-labelled compounds were prepared for fluorophore-assisted carbohydrate electrophoresis (face) separation. ants ... | 2001 | 11391813 |
| swarm intelligence. a whole new way to think about business. | what do ants and bees have to do with business? a great deal, it turns out. individually, social insects are only minimally intelligent, and their work together is largely self-organized and unsupervised. yet collectively they're capable of finding highly efficient solutions to difficult problems and can adapt automatically to changing environments. over the past 20 years, the authors and other researchers have developed rigorous mathematical models to describe this phenomenon, which has been du ... | 2001 | 11345907 |
| anaphylaxis caused by the new ant, pachycondyla chinensis: demonstration of specific ige and ige-binding components. | there have been no reports dealing with the pathogenic mechanism and ige-binding components in patients with anaphylaxis caused by a sting from pachycondyla chinensis. | 2001 | 11398091 |
| the guidance of desert ants by extended landmarks. | desert ants (cataglyphis fortis) were trained to follow a fixed route around a barrier to a feeder. their homeward trajectories were recorded on a test field containing a similar barrier, oriented either as in training or rotated through 22 or 45 . under one set of experimental conditions, the homeward trajectories rotated with the orientation of the barrier, implying that the visual features of this extended landmark can determine the route independently of compass cues: the barrier provided a ... | 2001 | 11398752 |
| biomechanics of the movable pretarsal adhesive organ in ants and bees. | hymenoptera attach to smooth surfaces with a flexible pad, the arolium, between the claws. here we investigate its movement in asian weaver ants (oecophylla smaragdina) and honeybees (apis mellifera). when ants run upside down on a smooth surface, the arolium is unfolded and folded back with each step. its extension is strictly coupled with the retraction of the claws. experimental pull on the claw-flexor tendon revealed that the claw-flexor muscle not only retracts the claws, but also moves the ... | 2001 | 11353847 |
| weeding and grooming of pathogens in agriculture by ants. | the ancient mutualism between fungus-growing ants and the fungi they cultivate for food is a textbook example of symbiosis. fungus-growing ants' ability to cultivate fungi depends on protection of the garden from the aggressive microbes associated with the substrate added to the garden as well as from the specialized virulent garden parasite escovopsis. we examined ants' ability to remove alien microbes physically by infecting atta colombica gardens with the generalist pathogen trichoderma virid ... | 2001 | 11375087 |
| coevolution in host-parasite systems: behavioural strategies of slave-making ants and their hosts. | recently, avian brood parasites and their hosts have emerged as model systems for the study of host-parasite coevolution. however, empirical studies of the highly analogous social parasites, which use the workers of another eusocial species to raise their own young, have never explicitly examined the dynamics of these systems from a coevolutionary perspective. here, we demonstrate interpopulational variation in behavioural interactions between a socially parasitic slave-maker ant and its host th ... | 2001 | 11375101 |
| species discrimination and population differentiation in ants using microsatellites. | this study was conducted to establish the regional scale of population differentiation of ants in the wheat belt of central western new south wales. microsatellite variation was surveyed at five loci in two morphologically similar ant species (designated "a" and "b") from the camponotus ephippium complex. three of the five scored microsatellite loci were highly variable with totals, in the two species, of 11, 13 and 42 alleles. the other loci had two and three alleles. the mean number of alleles ... | 2001 | 11106840 |
| biogeography and community structure of north american seed-harvester ants. | seed-harvester ants are a dominant and conspicuous insect group throughout arid portions of the southwestern united states and northern mexico, and they include approximately 75 species. intense study in the late 1970s and early 1980s led to the paradigm that interspecific competition for limited seed resources is the primary factor that structures seed-harvester ant communities. this review attempts to adjust this paradigm, suggesting that interspecific competition for food is probably less imp ... | 2001 | 11112162 |
| mating behavior and chemical communication in the order hymenoptera. | insects of the order hymenoptera are biologically and economically important members of natural and agro ecosystems and exhibit diverse biologies, mating systems, and sex pheromones. we review what is known of their sex pheromone chemistry and function, paying particular emphasis to the hymenoptera aculeata (primarily ants, bees, and sphecid and vespid wasps), and provide a framework for the functional classification of their sex pheromones. sex pheromones often comprise multicomponent blends de ... | 2001 | 11112163 |
| colony disassociation following diet partitioning in a unicolonial ant. | discriminating nestmates from alien conspecifics via chemical cues is recognized as a critical element in maintaining the integrity of insect societies. we determined, in laboratory experiments, that nestmate recognition in an introduced population of the argentine ant, linepithema humile, is modified by hydrocarbons acquired from insect prey, and that workers from spatially isolated colony fragments, each provided with prey that possessed distinct cuticular hydrocarbons, displayed aggressive be ... | 2001 | 11320891 |
| an antidiuretic factor in the forest ant: purification and physiological effects on the malpighian tubules. | formica polyctena antidiuretic factor (fopadf) was purified from a 15% trifluoroacetic acid (tfa) extract of the abdomens of 150,000 worker ants. after solid phase extraction of the crude extract and reversed-phase hplc on two c(18) columns, an antidiuretic factor was isolated. tested at a concentration of 1.0 ant-equivalents/µl (ant-eq/µl), the factor reversibly inhibited fluid secretion of isolated malpighian tubules to 29+/-5% (mean+/-se, n=24) of the control value. the same concentration of ... | 2001 | 11064025 |
| acceptance and intake of gel and liquid sucrose compositions by the argentine ant (hymenoptera: formicidae). | liquids and gels are common delivery forms used in commercial ant baits, but the relative effectiveness of each is unknown. we compared the feeding responses of the argentine ant, linepithema humile (mayr), to liquid and gel compositions of sucrose. in choice assays, more workers were counted on gel than liquid; however, substantially more liquid was consumed. because workers could stand on the gel, more workers could feed simultaneously on the gel. the feeding bouts of individual workers, howev ... | 2001 | 11332847 |
| monophyly and extensive extinction of advanced eusocial bees: insights from an unexpected eocene diversity. | advanced eusociality sometimes is given credit for the ecological success of termites, ants, some wasps, and some bees. comprehensive study of bees fossilized in baltic amber has revealed an unsuspected middle eocene (ca. 45 million years ago) diversity of eusocial bee lineages. advanced eusociality arose once in the bees with significant post-eocene losses in diversity, leaving today only two advanced eusocial tribes comprising less than 2% of the total bee diversity, a trend analogous to that ... | 2001 | 11172007 |
| ecological benefits of myrmecochory for the endangered chaparral shrub fremontodendron decumbens (sterculiaceae). | fremontodendron decumbens grows in a single county in central california, usa. prior research showed that its elaiosome-bearing seeds are dispersed by the harvester ant messor andrei. i tested several hypotheses regarding the positive role of ant-mediated dispersal to f. decumbens: (1) does ant-mediated seed dispersal facilitate seed escape from rodent predation?; (2) does ant processing of seeds stimulate germination?; (3) are ant middens more suitable microsites for seed or seedling survival i ... | 2001 | 11222246 |
| impact of four insecticides on japanese beetle (coleoptera: scarabaeidae) egg predators and white grubs in turfgrass. | field experiments were conducted to measure the effects of four commonly used turfgrass insecticides (isofenphos, diazinon, imidacloprid, halofenozide) on white grubs (coleoptera: scarabaeidae) and ant predators of white grub eggs. ant populations were measured over time with canned tuna, whereas predation by the ants was measured with artificially placed japanese beetle, popillia japonica newman, eggs. the effectiveness of each insecticide at controlling japanese beetle grubs, when applied at d ... | 2001 | 11233105 |
| lethal and sublethal effects of bendiocarb, halofenozide, and imidacloprid on harpalus pennsylvanicus (coleoptera: carabidae) following different modes of exposure in turfgrass. | routes by which nontarget predatory insects can be exposed to turfgrass pesticides include topical, residual, and dietary exposure. we used each of these routes to evaluate potential lethal or sublethal effects of two novel turfgrass insecticides, imidacloprid and halofenozide, and a carbamate, bendiocarb, on survival, behavior, and fecundity of the ground beetle harpalus pennsylvanicus degeer. field-collected carabids were exposed to direct spray applications in turf plots, fed food contaminate ... | 2001 | 11233134 |
| demographic mechanisms for the evolution of long life in social insects. | one of the most remarkable life history traits of many species of eusocial insects is the extraordinary longevity of their queens, with the recorded life span of some individuals exceeding 30 years. surprisingly, little research has been conducted on either the proximate or ultimate questions concerning what factors favor the evolution of the long life spans in social insects. the broad objective of this paper is to address four sets of questions: (1) what are the similarities and differences in ... | 2001 | 11295510 |
| food-plant niche selection rather than the presence of ant nests explains oviposition patterns in the myrmecophilous butterfly genus maculinea. | it has been suggested that the socially parasitic butterfly maculinea alcon detects ant odours before ovipositing on initial larval food plants near colonies of its obligate ant host myrmica ruginodis. it has also been suggested that overcrowding on food plants near m. ruginodis is avoided by an ability to detect high egg loads, resulting in a switch to selecting plants near less suitable ant species. if confirmed, this hypothesis (h1) would have serious implications for the application of curre ... | 2001 | 11296858 |
| colony structure of a slavemaking ant. i. intracolony relatedness, worker reproduction, and polydomy. | colony and population structure of the obligate slavemaker ant protomognathus americanus was analyzed via four nuclear microsatellite loci and mitochondrial dna (mtdna) markers. colonies of p. americanus usually contain a single queen, and here we show that she is singly inseminated. nestmate workers are generally full sisters and their relatedness does not deviate from the expected value of 0.75. even though colonies were strictly monogynous, we were able to infer that colony takeover by relate ... | 2001 | 11308088 |
| arthropods as predators of ticks (ixodoidea). | the existing information on arthropods as predators of ticks is based mainly on sporadic observations and their role in reducing tick populations and in most cases is still not clear. some reports suggest that in certain ecological habitats arthropods play an important role in the control of the tick population. this publication reports on some 100 relevant publications that appeared between 1906 and 1999. ants, beetles, and spiders seem to be the major arthropods preying on ticks. in general, e ... | 2001 | 11268678 |
| ants in space? | 2001 | 11287264 | |
| [spatial distribution of cordyceps spp. (ascomycotina: clavicipitaceae) and its impact on the ants in forests of amazonian colombian foothill]. | entomopathogenic fungi of the genus cordyceps were sampled in the foothills of the colombian amazon region (450-600 msnm altitude. january and may, 1998, i.e. dry and wet seasons, respectively). healthy and cordyceps-parasitized ants from a nearly pristine, a naturally disturbed and a human-disturbed forests were collected on 100 quadrants (1 m2) per forest. litter, shrubs and trunks were explored as substrates, and samples were gathered in vertical strata from 50 cm to 2 m high. azteca was the ... | 2001 | 12189826 |
| adaptations to biotic and abiotic stress: macaranga-ant plants optimize investment in biotic defence. | obligate ant plants (myrmecophytes) in the genus macaranga produce energy- and nutrient-rich food bodies (fbs) to nourish mutualistic ants which live inside the plants. these defend their host against biotic stress caused by herbivores and pathogens. facultative, 'myrmecophilic' interactions are based on the provision of fbs and/or extrafloral nectar (efn) to defending insects that are attracted from the vicinity. fb production by the myrmecophyte, m. triloba, was limited by soil nutrient conten ... | 2001 | 11559742 |
| a novel method for building regression tree models for qsar based on artificial ant colony systems. | among the multitude of learning algorithms that can be employed for deriving quantitative structure-activity relationships, regression trees have the advantage of being able to handle large data sets, dynamically perform the key feature selection, and yield readily interpretable models. a conventional method of building a regression tree model is recursive partitioning, a fast greedy algorithm that works well in many, but not all, cases. this work introduces a novel method of data partitioning b ... | 2001 | 11206370 |
| ants and agents: a process algebra approach to modelling ant colony behaviour. | process algebras are widely used in the analysis of distributed computer systems. they allow formal reasoning about how the various components of a system contribute to its overall behaviour. in this paper we show how process algebras can be usefully applied to understanding social insect biology, in particular to studying the relationship between algorithmic behaviour of individual insects and the dynamical behaviour of their colony. we argue that process algebras provide a useful formalism for ... | 2001 | 11565411 |
| qualitative and quantitative differences in cuticular hydrocarbons between laboratory and field colonies of pogonomyrmex barbatus. | ants held in the laboratory and field ants of the species pogonomyrmex barbatus have quantitative differences in their cuticular hydrocarbons and a qualitative difference in their methyl-branched hydrocarbons. laboratory-held workers showed twice the hydrocarbon content as field ants. this difference was mainly due to higher amounts of straight-chain alkanes and methyl-branched alkanes in laboratory ants, whereas the proportion of the alkenes remained the same for both groups. in addition to the ... | 2001 | 11567897 |
| seasonal patterns in the orientation system of the migratory ant pachycondyla marginata. | route directions of migrations by the neotropical termite-hunting ant pachycondyla marginata at a forest reserve in southeast brazil were analysed by circular statistic. colony movement patterns were compared between the rainy/hot and dry/cold seasons. migrations during the dry/cold season are significantly oriented 13 degrees with the magnetic north-south axis, while rainy/hot migrations do not exhibit a preferred direction. this result is discussed considering the hypothesis that p. marginata ... | 2001 | 11572016 |
| systematic analysis of oxidative degradation of polysaccharides using page and hplc--ms. | oxidation of polysaccharides yields hydroxyaldehydes and hydroxycarboxylic acids. aldehydes and carboxylic acids were separately conjugated to 8-aminonaphthalene-1,3,6-trisulfonic acid (ants) or tyrosine t-butyl ester (tbt). the ants-labeled derivatives were separated by molecular size on page gels and detected by fluorescence. tbt-labeled derivatives were separated by reverse phase chromatography on a c18-hplc column and analyzed by positive ion electrospray mass spectroscopy (hplc--ms). this c ... | 2001 | 11217956 |
| characterization of vitellogenin in the red imported fire ant, solenopsis invicta (hymenoptera: apocrita: formicidae). | vitellin (vn) and vitellogenin (vg) profiles were analyzed in monogyne and polygyne colonies of the red imported fire ant, solenopsis invicta. non-denaturing and sds-polyacrylamide gel electrophoresis (page) analyses indicated that the native vn was likely 350 kda and comprised of two subunits in the molecular size range of 170-185 kda. sds-page of hemolymph showed that the relative mobilities and subunit patterns of vg and vn were similar. vg was present in the hemolymph of reproductive queens; ... | 2001 | 11249942 |
| mating behaviour of rhytidoponera sp. 12 ants inferred from microsatellite analysis. | in the queenless ponerine ant rhytidoponera sp. 12, all workers have a spermatheca and functional ovaries and are potentially able to mate and reproduce. within a colony gamergates may either be full sisters to each other (type 1 colony), or they may not be full sisters but still be significantly related to each other (type 2 colony) due to daughter gamergates reproducing in their natal colonies after mating. despite many studies the mating behaviour of r. sp. 12 has been poorly understood. in t ... | 2001 | 11251795 |
| taste-enhancing effects of glycine on the sweetness of glucose: a gustatory aspect of symbiosis between the ant, camponotus japonicus, and the larvae of the lycaenid butterfly, niphanda fusca. | the lycaenid butterfly, niphanda fusca, has a parasitic relationship with its host ant, camponotus japonicus: the caterpillars may use chemical mimicry to enter the ant nest where they are fed mouth-to-mouth by the adult ants until pupation. nevertheless, larvae offer their host ants a nutritious secretion that contains 160 mm glucose and 43 mm glycine. using glucose and glycine mixture as artificial secretions, we investigated the gustatory effect of glucose and/or glycine on the ants. glycine ... | 2001 | 11595675 |
| responses of the ant lasius niger to various compounds perceived as sweet in humans: a structure-activity relationship study. | a behavioural study on the ant lasius niger was performed by observing its feeding responses to 85 compounds presented in a two-choice situation (tested compound versus water control or sucrose solution). among these compounds, only 21 were phagostimulating: six monosaccharides (d-glucose, 6-deoxy-d-glucose, l-galactose, l-fucose, d-fructose, l-sorbose), four derivatives of d-glucose (methyl alpha-d-glucoside, d-gluconolactone and 6-chloro- and 6-fluoro-deoxy-d-glucose), five disaccharides (sucr ... | 2001 | 11287382 |
| wind-induced ventilation of the giant nests of the leaf-cutting ant atta vollenweideri. | to understand the significance of elaborate nest architecture for the control of nest climate, we investigated the mechanisms governing nest ventilation in a large field nest of atta vollenweideri. surface wind, drawing air from the central tunnels of the nest mound, was observed to be the main driving force for nest ventilation during summer. this mechanism of wind-induced ventilation has so far not been described for social insect colonies. thermal convection, another possible force driving ve ... | 2001 | 11544898 |
| production of a cyanogenic secretion by a thyridid caterpillar (calindoea trifascialis, thyrididae, lepidoptera). | the thyridid caterpillar, calindoea trifascialis, when disturbed, emits a defensive secretion from two sac-like glands that open dorsolaterally on the first abdominal segment. the larva has two arm-like protuberances that project outward from the body just in front of the gland openings. these "arms", which are wetted by secretion when the larva activates its glands, appear to function specifically for administration of the fluid. a primary component of the secretion in mandelonitrile, a cyanoge ... | 2001 | 11544899 |
| changes in the cuticular hydrocarbon profile of the slave-maker ant queen, polyergus breviceps emery, after killing a formica host queen (hymenoptera: formicidae). | queens of the slave-maker ant, polyergus breviceps, take over nests of their formica host species by fatally attacking the resident queen. as workers only begin grooming the p. breviceps queen once she has ceased her attack, we investigated whether a change in parasite queen chemistry may account for the change in worker behavior. cuticular hydrocarbon profiles of newly mated p. breviceps queens and of queens of their two formica host species were found to be species-specific. profiles of newly ... | 2001 | 11545371 |
| segregation of colony odor in the desert ant cataglyphis niger. | there are two separate, and presumably opposing, processes that affect colony odor in the desert ant cataglyphis niger: (1) biosynthesis and turnover of these chemicals by individual ants, and (2) homogenization of colony odor through exchange of cues. the first increases signal variability; the latter decreases it. the impact of these factors was tested by splitting colonies and monitoring the profile changes occurring in the postpharyngeal glands (ppg) and cuticular hydrocarbons. from each of ... | 2001 | 11471945 |
| absolute configuration of anabasine from messor and aphaenogaster ants. | a method has been developed to assign the absolute configuration and enantiomeric excess of anabasine based on small amounts of material (in the microgram range), by derivatization with (+)-menthylchloroformate followed by capillary gc analysis of the resulting carbamate(s). this method was applied to three samples of anabasine isolated from messor and aphaenogaster ants. in messor sanctus, only (2's)-anabasine was present, whereas in aphaenogaster subterranea and a. miamiana (2's)-anabasine was ... | 2001 | 11471946 |
| appropriate and inappropriate use of immunotherapy. | the primary objective of this review is to discuss indications for appropriate and inappropriate use of allergen immunotherapy (it), including discussion of contraindications, adverse events, and alternative protocols and methods. | 2001 | 11476478 |
| the influence of the physical environment on the self-organised foraging patterns of ants. | among social insects such as ants, scouts that modulate their recruiting behaviour, following simple rules based on local information, generate collective patterns of foraging. here we demonstrate that features of the abiotic environment, specifically the foraging substrate, may also be influential in the emergence of group-level decisions such as the choice of one foraging path. experimental data and theoretical analyses show that the collective patterns can arise independently of behavioural c ... | 2001 | 11480704 |
| chemical profiles, division of labor and social status in pachycondyla queens (hymenoptera: formicidae). | queens of the neotropical ponerine ant pachycondyla cf. 'inversa' may co-operate during colony founding. one of several co-founding queens specializes in foraging, whereas the others remain in the nest and guard the brood. division of labor is achieved by aggressive interactions, which result in the formation of dominance hierarchies. gas chromatography and mass spectrometry of cuticular hydrocarbons obtained from live queens by spme revealed consistent differences between the patterns of cuticu ... | 2001 | 11480705 |
| individual versus social complexity, with particular reference to ant colonies. | insect societies colonies of ants, bees, wasps and termites--vary enormously in their social complexity. social complexity is a broadly used term that encompasses many individual and colony-level traits and characteristics such as colony size, polymorphism and foraging strategy. a number of earlier studies have considered the relationships among various correlates of social complexity in insect societies; in this review, we build upon those studies by proposing additional correlates and show how ... | 2001 | 11396847 |
| dufour glands in the hymenopterans (apidae, formicidae, vespidae): a review. | associated to the sting apparatus of the aculeate hymenopterans is found the poison gland, originated from the glands associated to the ovipositor of the non-aculeate hymenopterans and the less derived dufour gland, homologue of the coletterial gland of other insects, and found in all hymenopteran females. the dufour gland functions is mostly uncertain in hymenopterans but in ants it is involved with communication and defense and in non social bees with the nest building and protection. in wasps ... | 2001 | 11340467 |
| steric stabilization of fusogenic liposomes by a low-ph sensitive peg--diortho ester--lipid conjugate. | we describe the synthesis and characterization of a ph-sensitive poly(ethylene glycol)-diortho ester-distearoyl glycerol conjugate (pod). pod was prepared by a one-step synthesis, and its acid sensitivity characterized by tlc. the conjugate was found to be stable at neutral ph for greater than 3 h but degraded completely within 1 h at ph 5. liposomes composed of 10% of pod and 90% of a fusogenic lipid, dioleoyl phosphatidylethanolamine (dope) were readily prepared and remained stable for up to 1 ... | 2001 | 11312691 |
| structure of alkaloid 275a, a novel 1-azabicyclo[5.3.0]decane from a dendrobatid frog, dendrobates lehmanni: synthesis of the tetrahydrodiastereomers. | the principal alkaloid 275a in skins of the colombian poison frog dendrobates lehmanni has been identified as the pyrrolo[1,2-a]azepane (1), the first occurrence in nature of this "izidine" system. tetrahydro-1 proved identical to one of the four synthetic diastereomers, 2a--2d, thereby establishing that 1 has the 5z,10e relative stereochemistry. alkaloid 1 is often accompanied by other congeners, in particular a 5z,10z diastereomer 15, a dihydro analogue 16, and a ketone 17. such izidines in fr ... | 2001 | 11325220 |
| an oral bioassay for the toxicity of hydramethylnon to individual workers and queens of argentine ants, linepithema humile. | we have developed an oral bioassay to determine the toxicity of hydramethylnon to individual workers and queens of the argentine ant, linepithema humile. we fed seven concentrations of hydramethylnon in suspension to individual workers or queens, determined the amount of hydramethylnon ingested and evaluated the individual ants for mortality 14 days later. at concentrations > or = 0.37 g liter-1, the amount of liquid the queens ingested decreased dramatically, indicating that argentine ant queen ... | 2001 | 11721517 |
| do insects use templates or parameters for landmark navigation? | as an explanation for the landmark navigation abilities of insects, the template hypothesis is currently clearly dominating the parameter hypothesis. in a series of computer simulations, this paper investigates the conspicuous behavior of desert ants in experimental setups with expanded landmark arrays. it is shown that a parameter-based model accounts much better for the data than different template models. | 2001 | 11343429 |
| molecular analysis of phylogenetic relationships among myrmecophytic macaranga species (euphorbiaceae). | many species of the paleotropical pioneer tree genus macaranga thou. (euphorbiaceae) live in association with ants. various types of mutualistic interactions exist, ranging from the attraction of unspecific ant visitors to obligate myrmecophytism. in the latter, nesting space and food bodies are exchanged for protection by highly specific ant partners (mainly species of the myrmicine genus crematogaster). as a first step toward elucidating the coevolution of ant-plant interactions in the macaran ... | 2001 | 11399144 |
| a new type of exocrine gland and its function in mass recruitment in the ant cylindromyrmex whymperi (formicidae, cerapachyinae). | workers of the ant cylindromyrmex whymperi display mass trail recruitment. bioassays show that the trail pheromone originates from a unique gland between abdominal sternites 6 and 7. the gland has a hitherto unknown structural organization. upon leaving the secretory cell, the duct cell widens to form a sclerotized pear-shaped reservoir chamber, lined with multiple duct cells. each duct thus forms a miniature reservoir for the secretions of each single secretory cells, a novel structural arrange ... | 2001 | 11688416 |
| insecticidal activity of essential oils: octopaminergic sites of action. | a study was conducted to determine the insecticidal activity and mechanism of action of three essential oils (eugenol, alpha-terpineol and cinnamic alcohol) and an equal part mixture (3-blend) against american cockroaches (periplaneta americana). to address species differences in response to treatment with the test oils, carpenter ants (camponotus pennsylvanicus de geer), and german cockroaches (blattella germanica) were included in this study. exposed american cockroaches demonstrated hyperacti ... | 2001 | 11701389 |
| mandibular gland chemistry of four caribbean species of camponotus (hymenoptera: formicidae). | the volatile components of whole-body extracts of males, females and workers were analyzed in four species of neotropical ants in the formicine genus, camponotus. the species, c. kaura, c. sexguttatus, c. ramulorum and c. planatus, represent three different subgenera. volatile mandibular gland components were found only in male extracts in three of the species. in c. ramulorum, volatile components were found in male and female reproductives and workers. 3,4-dihydro-3,5-dihydroxy-6-methylpyran-4- ... | 2001 | 11399355 |
| sex ratio and wolbachia infection in the ant formica exsecta. | sex allocation data in social hymenoptera provide some of the best tests of kin selection, parent-offspring conflict and sex ratio theories. however, these studies critically depend on controlling for confounding ecological factors and on identifying all parties that potentially manipulate colony sex ratio. it has been suggested that maternally inherited parasites may influence sex allocation in social hymenoptera. if the parasites can influence sex allocation, infected colonies are predicted to ... | 2001 | 11703514 |
| antisocial, an intracellular adaptor protein, is required for myoblast fusion in drosophila. | somatic muscle formation in drosophila requires fusion of muscle founder cells with fusion-competent myoblasts. in a genetic screen for genes that control muscle development, we identified antisocial (ants), a gene that encodes an ankyrin repeat-, tpr repeat-, and ring finger-containing protein, required for myoblast fusion. in ants mutant embryos, founder cells and fusion-competent myoblasts are properly specified and patterned, but they are unable to form myotubes. ants, which is expressed spe ... | 2001 | 11709190 |
| integrative study on chromosome evolution of mammals, ants and wasps based on the minimum interaction theory. | there is well-known evidence that in many eukaryotes, different species have different karyotypes (e.g. n=1-47 in ants and n=3-51 in mammals). alternative (fusion and fission) hypotheses have been proposed to interpret this chromosomal diversity. although the former has long been accepted, accumulating molecular genetics evidence seems to support the latter. we investigated this problem from a stochastic viewpoint using the monte carlo simulation method under the minimum interaction theory. we f ... | 2001 | 11403567 |
| pets and vermin are associated with high endotoxin levels in house dust. | previous studies have shown that the risk for allergic sensitization is lower in children who grew up on farms and in young adults who were exposed to dogs in early childhood. a higher microbial exposure in general and in particular to endotoxin in early childhood might contribute to this lower risk of atopy. | 2001 | 11737034 |
| [nonconvulsive status epilepticus: experience in 33 patients]. | to review the nonconvulsive status epilepticus diagnosed in a general hospital in order to identify its frequency, electroclinical characteristics and response to medical treatment. patients ants and methods: a retrospective study of 33 cases of nonconvulsive status epilepticus was undertaken. the diagnosis was based on clinical and eeg manifestations. data regarding their clinical presentation, previous epilepsy, etiology of the status, its medical management and outcome were analysed. | 2001 | 11742619 |
| ammonia chemical ionization tandem mass spectrometry in structural determination of alkaloids. ii. tetraponerines from pseudomyrmecine ants. | chemical ionization tandem mass spectrometry (ci-ms/ms) of alkaloids with ammonia reagent gas and collision-activated dissociation as well as ei-ms/ms were applied to the tetraponerine alkaloids in extracts from six pseudomyrmecine ants of the genus tetraponera. the ms/ms techniques along with gas chromatography fourier transform infrared (gc/ftir) spectra allowed identification in two extracts of seven of the eight known tetraponerines. the ei-ms/ms fragmentations proved diagnostic for the ring ... | 2001 | 11507752 |
| structural infestations by imported fire ants: a survey with health implications. | this study provides the first baseline estimate of the impact of indoor ifa infestations in all 46 counties of our state. clinicians need to be alert to the threat of unprovoked stings and possible anaphylaxis among disabled or confined patients in a variety of indoor settings. | 2001 | 11434109 |
| toxicity of synthetic piperonyl compounds to leaf-cutting ants and their symbiotic fungus. | the development of leucoagaricus gongylophorus, the fungus cultured by the leaf-cutting ant atta sexdens was inhibited in vitro by synthetic compounds containing the piperonyl group. in addition, worker ants that were fed daily on an artificial diet to which these compounds were added had a higher mortality rate than the controls. the inhibition of the fungal growth increased with the size of the carbon side chain ranging from c1 through c8 and decreasing thereafter. 1-(3,4-methylenedioxybenzylo ... | 2001 | 11464791 |
| phase transition between disordered and ordered foraging in pharaoh's ants. | the complex collective behavior seen in many insect societies strongly suggests that a minimum number of workers are required for these societies to function effectively. here we investigated the transition between disordered and ordered foraging in the pharaoh's ant. we show that small colonies forage in a disorganized manner, with a transition to organized pheromone-based foraging in larger colonies. we also show that when food sources are difficult to locate through independent searching, thi ... | 2001 | 11493681 |
| contributions to and review of dicrocoeliosis, with special reference to the intermediate hosts of dicrocoelium dendriticum. | an epidemiological study on dicrocoeliosis caused by dicrocoelium dendriticum was carried out on sheep, molluscs and ants in the mountains of león province (nw spain) between 1987-1991. the results concerning the intermediate hosts and a review of some aspects of dicrocoeliosis are summarized. mollusc collection for the helminthological study was random throughout the study area at fortnightly intervals. twenty-nine gastropoda species were identified. d. dendriticum infection was only detected i ... | 2001 | 11769295 |
| arms races and the evolution of big fierce societies. | the causes of biological gigantism have received much attention, but only for individual organisms. what selection pressures might favour the evolution of gigantic societies? here we consider the largest single-queen insect societies, those of the old world army ant dorylus, single colonies of which can have 20 million workers. we propose that colony gigantism in dorylus arises as a result of an arms race and test this prediction by developing a size-structured mathematical model. we use this mo ... | 2001 | 11506686 |
| evidence of intracolony transmission of thelohania solenopsae (microsporidia: thelohaniidae) in red imported fire ants (hymenoptera: formicidae) and the first report of spores from pupae. | red imported fire ant, solenopsis invicta, colonies were infected horizontally by introducing live brood (mainly larvae and pupae) infected with thelohania solenopsae. live, infected brood introduced into uninfected colonies were adopted and raised to adulthood instead of being executed by the recipient colony. introductions of infected larvae with uninfected pupae, which eclose into adult worker caste fire ants, resulted in an 80% infection rate of the inoculated colonies. infections from intro ... | 2001 | 11812115 |
| [the use of insecticide fumigant canister to protect an insectarium and its residual effect against triatomine bugs, in laboratory conditions]. | an insecticide fumigant canister based on synthetic pyrethroids and dichlorvos was employed against cockroaches and ants which were invading an insectarium used for rearing triatominae. after removal of the triatominae, the canister was activated and found to kill all the invading insects within 48 hours. possible residual action against triatomines was then monitored by a 24-hour exposure of eggs, nymphs and adults of triatoma infestans, panstrongylus megistus and rhodnius neglectus in the trea ... | 2001 | 11813055 |
| a community of ants, fungi, and bacteria: a multilateral approach to studying symbiosis. | the ancient and highly evolved mutualism between fungus-growing ants and their fungi is a textbook example of symbiosis. the ants carefully tend the fungus, which serves as their main food source, and traditionally are believed to be so successful at fungal cultivation that they are able to maintain the fungus free of microbial pathogens. this assumption is surprising in light of theories on the evolution of parasitism, especially for those species of ants that have been clonally propagating the ... | 2001 | 11544360 |
| [effect of parameters of myrmecochorous syndrome on rates of removal of corydalis cava and pulmonaria obscura by formica polyctena ants]. | complex of adaptations of myrmecochorous plants to the ant dispersal composes so called myrmecochorous syndrome. to study the effect of some morphological and anatomical adaptations on diaspore attractiveness for ants, the field experiments with diaspores and their extracts were carried out. it was shown that chemical cues attracting ants are located in different parts of diaspores: in elaiosome only (c. cava) or in elaiosome, coverage of external layer of the fruit and in the fruit collar (p. o ... | 2001 | 11544770 |
| restricted effective queen dispersal at a microgeographic scale in polygynous populations of the ant formica exsecta. | ecological constraints on effective dispersal have been suggested to be a key factor influencing social evolution in animal societies as well as the shift from single queen colonies (monogyny) to multiple queen colonies (polygyny) in ants. however, little is known about the effective dispersal patterns of ant queens. here we investigate the microgeographic genetic structure of mitochondrial haplotypes in polygynous populations of the ant formica exsecta, both between pastures and among nests wit ... | 2001 | 11831664 |
| research of the holiday kind. ants. | 2001 | 11841007 | |
| [morphofunctional aspects of the head capsule topography in aculeata (hymenoptera)]. | according to degree of segmental fusion insect head is the most integrated part of the body. head skeleton subdivides into capsule and skeleton of appendages. exo- and endoskeleton (tentorium) of head capsule have complex segmental origin. marked margins are generally absent between such traditionally discriminated capsule parts as clypeus, frons, vertex, occiput, genae, etc. relative position to marked structures (appendages, eyes, ocelli, occipital foramen and etc.) defines the capsule parts, ... | 2001 | 11544773 |
| task-related environment alters the cuticular hydrocarbon composition of harvester ants. | within a colony of harvester ants (pogonomyrmex barbatus), workers in different task groups differ in the hydrocarbon composition of the cuticle. foragers and patrollers, which spend extended periods of time outside the nest, have a higher proportion of saturated, unbranched hydrocarbons (n-alkanes) on the cuticle than nest maintenance workers, which spend only short periods of time outside the nest. we tested whether these task-related differences in ant cuticular chemistry arise from exposure ... | 2001 | 11545372 |
| facultative and obligate slave making in formica ants. | here we show for the first time that the presumed facultative slave-making ant formica subintegra does not activate outside its nest until july and august, when it raids slaves. a comparative behavioral study of seasonal and daily activities, retrieval of prey, and nest maintenance of f. subintegra, the obligate slavemaker polyergus breviceps, and the facultative formica subnuda, shows that the behavioral repertory of f. subintegra closely resembles that of p. breviceps and clearly differs from ... | 2001 | 11572017 |
| prudent protomognathus and despotic leptothorax duloticus: differential costs of ant slavery. | the concept of ant slavery rests on the untested assumption that slave-making ants impose fitness costs on colonies of the species they raid. we tested that assumption by comparing the summertime seasonal productivity of leptothorax spp. colonies in field exclosures without slavemakers, with a colony of the obligatory slave-making ant protomognathus americanus, or with a colony of the obligatory slavemaker leptothorax duloticus. leptothorax longispinosus colonies placed in exclosures with p. ame ... | 2001 | 11572933 |
| evolution of myrmecophytism in western malesian macaranga (euphorbiaceae). | plants inhabited by ants (myrmecophytes) have evolved in a diversity of tropical plant lineages. macaranga includes approximately 300 paleotropical tree species; in western malesia there are 26 myrmecophytic species that vary in morphological specializations for ant association. the origin and diversification of myrmecophytism in macaranga was investigated using phylogenetic analyses of morphological and nuclear its dna characters and studies of character evolution. despite low its variation, th ... | 2001 | 11580014 |
| plant lock and ant key: pairwise coevolution of an exclusion filter in an ant-plant mutualism. | although observations suggest pairwise coevolution in specific ant-plant symbioses, coevolutionary processes have rarely been demonstrated. we report on, what is to the authors' knowledge, the strongest evidence yet for reciprocal adaptation of morphological characters in a species-specific ant-plant mutualism. the plant character is the prostoma, which is a small unlignified organ at the apex of the domatia in which symbiotic ants excavate an entrance hole. each myrmecophyte in the genus leonar ... | 2001 | 11600077 |
| a comparison of pitfall traps with bait traps for studying leaf litter ant communities. | a comparison of pitfall traps with bait traps for sampling leaf litter ants was studied in oak-dominated mixed forests during 1995-1997. a total of 31,732 ants were collected from pitfall traps and 54,694 ants were collected from bait traps. they belonged to four subfamilies, 17 genera, and 32 species. bait traps caught 29 species, whereas pitfall traps caught 31 species. bait traps attracted one species not found in pitfall traps, but missed three of the species collected with pitfall traps. co ... | 2001 | 11425034 |
| quantification of insect nitrogen utilization by the venus fly trap dionaea muscipula catching prey with highly variable isotope signatures. | dionaea is a highly specialized carnivorous plant species with a unique mechanism for insect capture. the leaf is converted into an osmotically driven trap that closes when an insect triggers sensory trichomes. this study investigates the significance of insect capture for growth of dionaea at different successional stages after a fire, under conditions where the prey is highly variable in its isotope signature. the contribution of insect-derived nitrogen (n) was estimated using the natural abun ... | 2001 | 11432920 |
| a brief history of forensic entomology. | apart from an early case report from china (13th century) and later artistic contributions, the first observations on insects and other arthropods as forensic indicators were documented in germany and france during mass exhumations in the late 1880s by reinhard and hofmann, whom we propose recognizing as co-founders of the discipline. after the french publication of mégnin's popular book on the applied aspects of forensic entomology, the concept quickly spread to canada and the us. at the time, ... | 2001 | 11457602 |
| behavioral and chemical analysis of venom gland secretion of queens of the ant solenopsis geminata. | bioassays in a y-tube olfactometer showed that workers of solenopsis geminata (hymenoptera: formicidae) were attracted to venom gland extracts of queens. gas chromatography coupled mass spectrometry analysis of individual glands of queens of s. geminata showed that the secretion is composed mainly of a large amount of 2-alkyl-6-methylpiperidine alkaloids and a tiny amount of a delta-lactone and a a-pyrone, which have been earlier identified as components of the queen attractant pheromone of sole ... | 2001 | 11789950 |
| inhibition of neurogenic inflammation by the amazonian herbal medicine sangre de grado. | this study was designed to determine if the amazonian medicinal sangre de grado, confers benefit by suppressing the activation of sensory afferent nerves. methods: (i) vasorelaxation of rat mesenteric arteries in response to calcitonin gene-related peptide; (ii) rat paw edema in response to protease- activating peptide receptor 2-activating peptide; (iii) rat paw hyperalgesia in response to low-dose protease-activating peptide receptor 2-activating peptide or prostaglandin e2; (iv) gastric hyper ... | 2001 | 11564183 |
| complex determination of queen body size in the queen size dimorphic ant leptothorax rugatulus (formicidae: hymenoptera). | in order to understand the evolution of natural variability, and polymorphisms in particular, it is essential to study proximate causes. our study is the first work on ants to determine formally the heritability of quantitative traits in a quantitative genetic framework. we investigated the causes of queen size dimorphism of the ant leptothorax rugatulus and derive from the results a possible scenario for its evolutionary maintenance. mother size was highly predictive of daughter size in field c ... | 2001 | 11678985 |
| genetic variability and social structure of colonies in acromyrmex heyeri and a. striatus (hymenoptera: formicidae). | the breeding structure of both colony and population of social insects can be examined by genetic analysis. colonies of the leaf-cutting ants acromyrmex heyeri and a. striatus (myrmicinae, attini) were thus analyzed for isoenzyme systems mdh, a-gpdh, and amy to describe genotype variability and social structure. a total of five loci were investigated (three for amylase and one for each other system). ninety-seven colonies of a. heyeri and 103 of a. striatus were sampled in different localities i ... | 2001 | 12071324 |
| field and allozyme studies investigating optimal mating success in two sympatric spring-ephemeral plants, trillium erectum and t. grandiflorum. | a combination of field experiments and allozyme studies was used to test whether two spring-ephemeral plants growing in eastern north america, trillium erectum and t. grandiflorum (liliaceae), exhibited an optimal outcrossing distance for fruit and seed production. furthermore, the spatial genetic structure of the trillium populations was examined in light of the outcrossing results. in field experiments, recipient plants were pollinated with either self pollen or with pollen from donors growing ... | 2001 | 11703508 |
| trade-off between chemical and biotic antiherbivore defense in the south east asian plant genus macaranga. | the plant genus macaranga is known for its manifold mutualistic associations with ants. the plants provide food for the ants and in turn get protection from herbivores. depending on the strength of the plant-ant interaction, the plant's investment in ants and the biotic defense derived from them is more or less effective. we conducted a comparative study on tannin content in 12 macaranga species that were selected based on their associations with ants (three nonmyrmecophytes and nine myrmecophyt ... | 2001 | 11710606 |
| ecological meltdown in predator-free forest fragments. | the manner in which terrestrial ecosystems are regulated is controversial. the "top-down" school holds that predators limit herbivores and thereby prevent them from overexploiting vegetation. "bottom-up" proponents stress the role of plant chemical defenses in limiting plant depredation by herbivores. a set of predator-free islands created by a hydroelectric impoundment in venezuela allows a test of these competing world views. limited area restricts the fauna of small (0.25 to 0.9 hectare) isla ... | 2001 | 11729317 |
| model of droplet dynamics in the argentine ant linepithema humile (mayr). | the formation of droplets of ants linepithema humile (mayr) is observed under certain experimental conditions: a fluctuating aggregate forms at the end of a rod and a droplet containing up to 40 ants eventually falls down. when the flux of incoming ants is sufficient, this process can continue for several hours, leading to the formation and fall of tens of droplets. previous work indicates that the time series of drop-to-drop intervals may result from a nonlinear low-dimensional dynamics, and th ... | 2001 | 11732177 |
| two-category model of task allocation with application to ant societies. | in many network models of interacting units such as cells or insects, the coupling coefficients between units are independent of the state of the units. here we analyze the temporal behavior of units that can switch between two 'category' states according to rules that involve category-dependent coupling coefficients. the behaviors of the category populations resulting from the asynchronous random updating of units are first classified according to the signs of the coupling coefficients using nu ... | 2001 | 11732179 |
| partial incompatibility between ants and symbiotic fungi in two sympatric species of acromyrmex leaf-cutting ants. | we investigate the nature and duration of incompatibility between certain combinations of acromyrmex leaf-cutting ants and symbiotic fungi, taken from sympatric colonies of the same or a related species. ant-fungus incompatibility appeared to be largely independent of the ant species involved, but could be explained partly by genetic differences among the fungus cultivars. following current theoretical considerations, we develop a hypothesis, originally proposed by s. a. frank, that the observed ... | 2001 | 11761059 |
| mandible movements in ants. | ants use their mandibles for almost any task, including prey-catching, fighting, leaf-cutting, brood care and communication. the key to the versatility of mandible functions is the mandible closer muscle. in ants, this muscle is generally composed of distinct muscle fiber types that differ in morphology and contractile properties. fast contracting fibers have short sarcomeres (2-3 microm) and attach directly to the closer apodeme, that conveys the muscle power to the mandible joint. slow but for ... | 2001 | 11733162 |
| on-line capillary electrophoresis with mass spectrometry detection for the analysis of carbohydrates after derivatization with 8-aminonaphthalene-1,3,6-trisulfonic acid. | capillary electrophoresis (ce) with mass spectrometry (ms) detection is an ideal tool for analytical use, which combines a nano quantity assay with mass determination. carbohydrate analysis has always been a challenge because of the inherent structural complexity and the lack of a chromophore, unless derivatization is used. here we use the derivatization of carbohydrates with a fluorophore, 8-aminonaphthalene-1,3,6-trisulfonic acid (ants). this chromophore has two advantages, first, it facilitat ... | 2001 | 11762766 |
| effects of aromatic cedar mulch on the argentine ant and the odorous house ant (hymenoptera: formicidae). | in laboratory studies, the argentine ant, linepithema humile (mayr), and the odorous house ant, tapinoma sessile (say), avoided aromatic cedar mulch as a nesting substrate. both ant species were killed when confined with fresh aromatic cedar mulch in sealed containers. however, when confined with cedar mulch that had been aged outdoors for up to 140 d, mortality of l. humile was complete regardless of mulch age, whereas t. sessile mortality declined significantly over the mulch-aging period. arg ... | 2001 | 11777059 |
| egocentric information helps desert ants to navigate around familiar obstacles. | homing ants have been shown to associate directional information with familiar landmarks. the sight of these local cues might either directly guide the path of the ant or it might activate a landmark-based vector that points towards the goal position. in either case, the ants define their courses within allocentric systems of reference. here, we show that desert ants, cataglyphis fortis, forced to run along a devious path can use egocentric information as well. the ants were trained to deviate f ... | 2001 | 11815643 |
| down the tube: pollinators, predators, and the evolution of flower shape in the alpine skypilot, polemonium viscosum. | we address how a conflict between pollinator attraction and avoidance of flower predation influences the evolution of flower shape in polemonium viscosum. flower shape in p. viscosum is the product of an isometric relationship between genetically correlated (ra = 0.70) corolla flare and length. bumblebee pollinators preferentially visit flowers that are more flared and have longer tubes, selecting for a funnel-shaped corolla. however, flower shape also influences nectar-foraging ants that sever ... | 2001 | 11761057 |
| development of thelohania solenopsae in red imported fire ants solenopsis invicta from polygynous colonies results in formation of three spore types. | 2001 | 11906091 | |
| stinging ants. | ants belong to the order hymenoptera, along with bees, wasps, yellow jackets, etc., they are the most successful animal genera in this world. it is their selfless social structure which accounts for their huge impact. their effect on man ranges from the parasol ant, which makes plant cultivation untenable in certain parts of south america, to solenopsis invicta in the southeastern united states of america, which kill ground dwelling birds and small animals, harass livestock, and renders farmland ... | 2001 | 11964710 |
| [distantly received pheromone-primer controls cessation of diapause in the ant myrmica rubra l. (hymenoptera, formicidae)]. | 2001 | 11642158 | |
| how do ants stick out their tongues? | the mouthparts are very important tools for almost any task performed by ants. in particular, the labiomaxillary complex is essential for food intake. in the present study we investigated the anatomical design of the labiomaxillary complex in various ant species, focusing on movement mechanisms. six labial and six maxillary muscles with different functions control the several joints and ensure the proper performance of the labiomaxillary complex. according to our measurements of sarcomere length ... | 2002 | 12219342 |
| field evaluation of potential of alarm pheromone compounds to enhance baits for control of grass-cutting ants (hymenoptera: formicidae). | leaf-cutting ants are important economic pests of the neotropics, and the most common method of control involves the use of insecticidal baits. baits that are currently available exhibit low attractiveness to grass-cutting species, thus there is a need to develop improved baits. the potential for using alarm pheromone compounds to enhance the attractiveness and subsequent harvest of baits was examined for two economically important species of grass-cutting ant, atta bisphaerica (forel) and atta ... | 2002 | 12075997 |