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Tschinkel Walter R - - 2005
The architecture of subterranean nests of the ant Camponotus socius was studied from casts of plaster or metal. Twenty-four such casts are illustrated using stereo pairs of images. After study, plaster casts were dissolved to retrieve the workers embedded in them, providing a census of the ants that excavated the ...
Jackson Duncan E - - 2004
Pheromone trails are used by many ants to guide foragers between nest and food. But how does a forager that has become displaced from a trail know which way to go on rejoining the trail? A laden forager, for example, should walk towards the nest. Polarized trails would enable ants ...
Dally Joanna M - - 2004
In the presence of conspecifics, food-caching western scrub-jays (Aphelocoma californica) implement a variety of strategies to reduce the chances of cache theft. This experiment aimed to determine whether the jays could exploit an environmental variable, the level of ambient light, to reduce the transfer of visual information to potential pilferers. ...
Ducoing A M - - 2004
The authors investigated whether Tonkean macaques (Macaca tonkeana) can distinguish between 2 group mates with different knowledge and improve their foraging performance. The subjects were 8 young individuals belonging to a group raised in a 2-acre park. The authors carried out 192 tests in which subgroups of 3 individuals were ...
Waghorn G C - - 2004
Perennial ryegrass is the primary forage component of ruminant diets in New Zealand. It is persistent and palatable, and immature ryegrass has a high nutritive value (NV). However, seedhead development substantially lowers its feeding value (FV) as fibre concentration increases, the rate and extent of digestibility decreases, and voluntary intake ...
Rutter Matthew T - - 2004
Cost-benefit models of the evolution of mutualism predict that the current state of mutualism results from trade-offs between fitness costs of mutualist traits and the fitness benefits of association. We test the assumptions of such models by measuring patterns of natural selection on a mutualist trait, extrafloral nectar production in ...
Gros-Louis Julie - - 2004
In the context of foraging, many animal species produce specific calls that attract others. Researchers hypothesize that these vocalizations function to inform others about food; however, few studies have investigated whether food-associated calls alone are sufficient to cause individuals to respond as if they have been informed about food. Playback ...
Leoncini Isabelle - - 2004
Previous research showed that the presence of older workers causes a delayed onset of foraging in younger individuals in honey bee colonies, but a specific worker inhibitory factor had not yet been identified. Here, we report on the identification of a substance produced by adult forager honey bees, ethyl oleate, ...
LeBrun Edward G - - 2005
A wide variety of animal communities are organized into interspecific dominance hierarchies associated with the control and harvest of food resources. Interspecific dominance relationships are commonly found to be linear. However, dominance relations within communities can form a continuum ranging from intransitive networks to transitive, linear dominance hierarchies. How interference ...
Korb Judith - - 2005
Social insect colonies are not the harmonious entities they were once considered. Considerable conflicts exist between colony members, as has been shown for Hymenoptera. For termites, similar studies are lacking, but aggressive manipulations have been claimed to regulate sexual development, and even to account for the evolution of workers. This ...
Huey, Raymond B.
Desert lizards are typically either widely foraging or sit-and-wait predators, and these foraging modes are correlated with major differences in ecology. Foraging mode is related to the type of prey eaten by lizards. Widely foraging lizards in the Kalahari desert, the Western Australian desert, and the North American desert generally ...
Held S - - 2005
This experiment investigated whether domestic pigs can remember the locations of food sites of different relative value, and how a restricted retrieval choice affects their foraging behaviour. Nine juvenile female pigs were trained to relocate two food sites out of a possible eight in a spatial memory task. The two ...
Hoffmann Joscelyn N - - 2004
Meissner corpuscles (MCs) are specialized mechanoreceptors located exclusively in the papillae of glabrous skin. They are confined largely to cutaneous pads of the extremities and respond to transient, phasic, or vibratory stimuli. Though absent in most eutherian taxa, MCs are reported in all primates studied, being most developed in modern ...
Sivakumaran Subathira - - 2004
The proanthocyanidin polymer fractions of the leaves of the forage legume Dorycnium rectum were analysed by acid catalysis with benzyl mercaptan, NMR and ES-MS. The results showed that D. rectum differs from other temperate proanthocyanidin-containing forage legumes in that the range of polymers extends up to very high degrees of ...
Nilsson P Anders - - 2004
The food intake rate of foragers may be reduced as a result of interference, which may be asymmetric among individuals and occur as a result of intimidation, direct aggression or filtering. It is important to distinguish among these types of interference, because each can have different consequences for individuals, foraging ...
Nieh James C - - 2004
Signals that are perceived over long distances or leave extended spatial traces are subject to eavesdropping. Eavesdropping has therefore acted as a selective pressure in the evolution of diverse animal communication systems, perhaps even in the evolution of functionally referential communication. Early work suggested that some species of stingless bees ...
Swoboda L E - - 2004
Laboratory assays were conducted to determine whether physical guidelines could direct subterranean termite foraging behavior. Several materials (wood, plastics, and wood thermoplastic composites) were evaluated for their potential to serve as termite guidelines. Termite tunneling along the different types of guidelines was measured. The proportion of baits discovered when connected ...
Jungnickel H - - 2004
Inter-colonial aggression was tested using three colonies of Scaptotrigona bipunctata in a natural setting when their nests were moved and by artificial contact between individuals. Examination of the cuticular lipids of individuals from two colonies kept under identical conditions showed clear differences in their cuticular hydrocarbon profiles. The cuticular lipids ...
Kober, Kerstin
Only little is known of migratory shorebirds in the tropics. The objective of this thesis was to describe the environment, the food availability, the bird community, the relationship between birds and environment and the avian consumption at tropical tidal flats. The study was conducted at tidal flats in the Northeast ...
Shochat Eyal - - 2004
Urban bird communities exhibit high population densities and low species diversity, yet mechanisms behind these patterns remain largely untested. We present results from experimental studies of behavioral mechanisms underlying these patterns and provide a test of foraging theory applied to urban bird communities. We measured foraging decisions at artificial food ...
Cory S. Sheffield
Epeoloides pilosula (Cresson) (Hymenoptera: Apidae), a cleptoparasitic bee thought to be extinct, was recently discovered in Nova Scotia, Canada. This, the first documented capture in over 60 years, expands the reported range of this species in North America which coincides with that of its host, bees of the genus Macropis ...
Lynch D H - - 2004
Perennial forages may be ideally suited for fertilization with slow N release amendments such as composts, but difficulties in predicting N supply from composts have limited their routine use in forage production. A field study was conducted to compare the yield and protein content of a binary legume-grass forage mixture ...
Rutishauser Matthew R - - 2004
In comparison with other homeotherms, young recently weaned marine mammals in high latitudes face exceptional energetic demands when foraging and thermoregulating. Lipids are an important source of energy and a major component of insulation that allows them to meet these demands. To examine the role of lipid stores in a ...
Sánchez Daniel - - 2004
Several studies have examined the existence of recruitment communication mechanisms in stingless bees. However, the spatial accuracy of location-specific recruitment has not been examined. Moreover, the location-specific recruitment of reactivated foragers, i.e., foragers that have previously experienced the same food source at a different location and time, has not been ...
Goldstone Robert L - - 2004
We have developed an experimental platform that allows a large number of human participants to interact in real time within a common virtual world. Within this environment, human participants foraged for resources distributed in two spatially separated pools. In addition to varying the relative replenishment rate for the two pools ...
Richard Freddie-Jeanne - - 2004
This study reports new information on interactions between Ectatomma tuberculatum (Ponerinae) and Crematogaster limata parabiotica (Myrmicinae). Workers of these sympatric arboreal ant species forage on the same pioneer trees. Diurnally, Ectatomma preyed on Crematogaster workers that avoided overt aggression by respecting a 'safe distance'. At night, Crematogaster initiated raids within ...
Jeschke Jonathan M - - 2004
The functional response of a consumer is the relationship between its consumption rate and the abundance of its food. A functional response is said to be of type I if consumption rate increases linearly with food abundance up to a threshold level at which it remains constant. According to conventional ...
Helms Ken R - - 2004
A recent study by Fournier et al. (2003) provides important new information on sex allocation in the ant Pheidole pallidula, and proposes a new scenario for sex-ratio evolution in P. pallidula and similar species. However, Helms proposed to the authors that two important conclusions of the study were questionable because ...
Hrncir M - - 2004
Using a laser vibrometer we studied the influence of the food's sugar concentration on different parameters of the thorax vibrations produced by foragers of Melipona seminigra during trophallaxis in the nest. The concentrations tested (20-70% sugar w/w) were within the biologically relevant range. They substantially influenced different parameters of the ...
Dussutour Audrey - - 2004
Efficient transportation, a hot topic in nonlinear science, is essential for modern societies and the survival of biological species. Biological evolution has generated a rich variety of successful solutions, which have inspired engineers to design optimized artificial systems. Foraging ants, for example, form attractive trails that support the exploitation of ...
ROBERT J. SMITH
Lowland coniferous forests adjacent to northern Lake Huron provide important stopover habitat for landbirds during spring migration. Large numbers of aquatic insects emerging from nearshore waters of northern Lake Huron appear to be an important food source. In this study we compared the foraging behavior of a long-distance landbird migrant, ...
Decourtye Axel - - 2004
We have compared the sublethal effects of two insecticides in the honeybee (imidacloprid and deltamethrin) in both semi-field and laboratory conditions. A sugar solution containing 24 microg kg(-1) of imidacloprid or 500 microg kg(-1) of deltamethrin was offered to a colony set in an outdoor flight cage. In contrast to ...
Luttik R - - 2004
To describe the grit in bird gizzards, we examined the gizzard content of some 200 birds of varying size and diet (e.g., granivores and nongranivores). Grit use (frequency, size, amount, and shape) was characterized for 27 bird species that forage, at least part of the year, on arable land in ...
Tinette S - - 2004
In Drosophila melanogaster food search behaviour, groups of flies swarm around and aggregate on patches of food. We wondered whether flies explore their environment in a cooperative way as interactions between individual flies within a population might influence the flies' ability to locate food sources. We have shown that the ...
Reinhard Judith - - 2004
The honeybee, Apis mellifera, navigates rapidly and accurately to food sources that are often kilometres away. They achieve this by learning visual cues, such as the location and colour of nectar-bearing flowers, and chemical cues, such as the scent and the taste of the nectar. Here we train bees to ...
Gauvin Shawn - - 2004
Group feeding animals experience a number of competitive foraging costs that may result in a lowered feeding rate. It is important to distinguish between reductions in feeding rates that are caused by reduced food availability and physical interactions among foragers from those caused by the mere presence of foraging companions ...
Cowlishaw Guy - - 2004
It is commonly assumed that anti-predator vigilance by foraging animals is costly because it interrupts food searching and handling time, leading to a reduction in feeding rate. When food handling does not require visual attention, however, a forager may handle food while simultaneously searching for the next food item or ...
Saunders, Anthony S. J.
Densities and behaviour of Noisy Friarbirds Philemon corniculatus and Red Wattlebirds Anthochaera carunculata were measured during 1992 and 1993 at six sites along an east-west transect through central New South Wales from the Central Coast through to the Central Western Slopes, and at Goobang National Park from 1993 to 1996. ...
TIMOTHY C. CARTER
We evaluated partitioning of food resources among syntopic eastern red (Lasiurus borealis), Seminole (L. seminolus) and evening (Nycticeius humeralis) bats at the Savannah River Site, South Carolina, from June through August of 1996 and 1997. We compared diets to indices of relative prey availability, which were based on samples of ...
Breed Michael D - - 2004
One key advantage of eusociality is shared defense of the nest, brood, and stored food; nest defense plays an important role in the biology of eusocial bees. Recent studies on honey bees, Apis mellifera, have focused on the placement of defensive activity in the overall scheme of division of labor, ...
Scortichini G - - 2004
The Istituto Zooprofilattico dell'Abruzzo e del Molise 'G. Caporale' (IZS A&M) has been monitoring contamination of food by the polychlorinated dibenzodioxins (PCDD) and polychlorinated dibenzo-furans (PCDF) as part of the National Surveillance Plan (NSP) in Italy since 1999, on license from the Italian Ministry of Health. Between 1999 and 2000, ...
Pravosudov Vladimir V - - 2003
It is widely assumed that chronic stress and corresponding chronic elevations of glucocorticoid levels have deleterious effects on animals' brain functions such as learning and memory. Some animals, however, appear to maintain moderately elevated levels of glucocorticoids over long periods of time under natural energetically demanding conditions, and it is ...
ROBERT C. DOBBS
We discovered and monitored a nest of the Rusty-winged Barbtail (Premnornis guttuligera) on the eastern slope of the Andes in Napo Province, Ecuador. The nest, in a hollow Cyathea tree-fern snag, was a deep cup composed entirely of Cyathea tree-fern petiole scales (ramenta). A single nestling fledged successfully on 13 ...
Dubois Frédérique - - 2003
Although many variants of the hawk-dove game predict the frequency at which group foraging animals should compete aggressively, none of them can explain why a large number of group foraging animals share food clumps without any overt aggression. One reason for this shortcoming is that hawk-dove games typically consider only ...
Marley C L - - 2003
Studies in New Zealand and the UK have shown that lambs grazing birdsfoot trefoil (Lotus corniculatus) or chicory (Cichorium intybus) have reduced parasite intensities compared to lambs grazing ryegrass swards. However, data in the literature on the influence of forages on helminth parasites is equivocal and the underlying mechanisms by ...
Cole Mark R - - 2003
In Experiment 1, rats foraged for food in six successive phases with 8, 16, 24, 32, 40, and 48 arms attached in random locations to a large radial maze. The percentage of novel choices appeared to be determined more by spatial proximity than by number of arms. In Experiment 2, ...
Nieh James C - - 2003
Research on bee communication has focused on the ability of the highly social bees, stingless bees (Hymenoptera, Apidae, Meliponini) and honeybees (Apidae, Apini), to communicate food location to nest-mates. Honeybees can communicate food location through the famous waggle dance. Stingless bees are closely related to honeybees and communicate food location ...
Silva Erin M - - 2003
Onion (Allium cepa L.) seed production has long been plagued with yield problems because of lack of pollination by the honey bee, Apis mellifera L. To attempt to attract more pollinators to the onion seed production field, honey bees were conditioned to associate onion floral odor components with a reward. ...
Guisinger Shan - - 2003
Anorexia nervosa (AN) is commonly attributed to psychological conflicts, attempts to be fashionably slender, neuroendocrine dysfunction, or some combination of these factors. Considerable research reveals these theories to be incomplete. Psychological and societal factors account for the decision to diet but not for the phenomenology of the disorder; theories of ...
Durier Virginie - - 2003
Insects are thought to pinpoint a place by using memorized "snapshots," i.e., two-dimensional retinotopic views of the surrounding landmarks recorded when at the place (reviewed in ). Insects then reach the place by moving until their current view matches their snapshot. To determine when snapshots are recalled, and how differences ...
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