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Korb Judith - - 2008
Ants and termites are the most abundant animals on earth. Their ecological success is attributed to their social life. They live in colonies consisting of few reproducing individuals, while the large majority of colony members (workers/soldiers) forego reproduction at least temporarilly. Despite their apparent resemblance in social organisation, both groups ...
Okada R - - 2008
A honeybee informs her nestmates of the location of a flower she has visited by a unique behavior called a "waggle dance." On a vertical comb, the direction of the waggle run relative to gravity indicates the direction to the food source relative to the sun in the field, and ...
Schaefer H Martin - - 2008
Foraging behaviour is an essential ecological process linking different trophic levels. A central assumption of foraging theory is that food selection maximises the fitness of the consumer. It remains unknown, however, whether animals use innate or learned behaviour to discriminate food rewards. While many studies demonstrated that previous experience is ...
Goulson D - - 2008
Declines in bumble bee species in the past 60 years are well documented in Europe, where they are driven primarily by habitat loss and declines in floral abundance and diversity resulting from agricultural intensification. Impacts of habitat degradation and fragmentation are likely to be compounded by the social nature of ...
Sato Katsufumi - - 2008
To understand the foraging strategies of free-ranging diving animals, time series information on both foraging effort and foraging success is essential. Theory suggests that wing stroke frequency for aerial flight should be higher in heavier birds. Based on this premise, we developed a new methodology using animal-borne accelerometers to estimate ...
Su Songkun - - 2008
The honeybee waggle dance, through which foragers advertise the existence and location of a food source to their hive mates, is acknowledged as the only known form of symbolic communication in an invertebrate. However, the suggestion, that different species of honeybee might possess distinct 'dialects' of the waggle dance, remains ...
Ridley Amanda R - - 2007
Audience effects are increasingly recognized as an important aspect of intraspecific communication. Yet despite the common occurrence of interspecific interactions and considerable evidence that individuals respond to the calls of heterospecifics, empirical evidence for interspecific audience effects on signalling behaviour is lacking. Here we present evidence of an interspecific audience ...
Greene Michael J - - 2007
Recruitment to food or nest sites is well known in ants; the recruiting ants lay a chemical trail that other ants follow to the target site, or they walk with other ants to the target site. Here we report that a different process determines foraging direction in the harvester ant ...
Isbell Lynne A - - 2007
The ants that live in the swollen thorns (domatia) of Acacia drepanolobium are staple foods for patas monkeys (Erythrocebus patas). To obtain a better understanding of these insects as resources for patas monkeys, we sampled the contents of 1,051 swollen thorns (ant domatia) over a 22-month period from December 1999 ...
Endlein Thomas - - 2008
The hymenopteran tarsus is equipped with claws and a movable adhesive pad (arolium). Even though both organs are specialised for substrates of different roughness, they are moved by the same muscle, the claw flexor. Here we show that despite this seemingly unfavourable design, the use of arolium and claws can ...
Houston Alasdair I - - 2007
In order to avoid both starvation and disease, animals must allocate resources between energy reserves and immune defence. We investigate the optimal allocation. We find that animals with low reserves choose to allocate less to defence than animals with higher reserves because when reserves are low it is more important ...
Dailey Megan E - - 2008
Unlike most species, after food deprivation, Siberian hamsters increase foraging and food hoarding, two appetitive ingestive behaviors, but not food intake, a consummatory ingestive behavior. We previously demonstrated (Wood AD, Bartness TJ, Am J Physiol Regul Integr Comp Physiol 272: R783-R792, 1997) that increases in food hoarding are triggered by ...
Kawaguchi Lina G - - 2007
Animals exploiting their familiar food items often avoid spatio-temporal aggregation with others by avoiding scents, less rewarding areas or visual contacts, thereby minimizing competition or interference when resources are replenished slowly in patches. When animals are searching or assessing available food sources, however, they may benefit from reducing sampling costs ...
Osborne Juliet L - - 2008
1. Foraging range is a key aspect of the ecology of 'central place foragers'. Estimating how far bees fly under different circumstances is essential for predicting colony success, and for estimating bee-mediated gene flow between plant populations. It is likely to be strongly influenced by forage distribution, something that is ...
O'Donnell D L - - 2007
Aedes albopictus (Skuse) (Diptera: Culicidae) invaded the United States in 1985 and spread rapidly across eastern North America, whereas Aedes japonicus (Theobald) invaded and became established in the United States more recently (1998). The two species may co-occur in container habitats, and they are of potential public health concern as ...
Reynolds Andrew M - - 2007
The foraging strategies used by animals are key to their success in spatially and temporally heterogeneous environments. We hypothesise that when a food source at a known location ceases to be available, flying insects will exhibit search patterns that optimise the rediscovery of such resources. In order to study these ...
Bugnyar Thomas - - 2007
Complex social behavior builds on the mutual judgment of individuals as cooperation partners and competitors [1]. Play can be used for assessing the others' dispositions in humans and nonhuman mammals [2], whereas little is known about birds. Recently, food-caching corvids have been found to rival primates in their ability to ...
Moore Jeffrey E - - 2007
Scatter-hoarding rodents should space food caches to maximize cache recovery rate (to minimize loss to pilferers) relative to the energetic cost of carrying food items greater distances. Optimization models of cache spacing make two predictions. First, spacing of caches should be greater for food items with greater energy content. Second, ...
Loureiro Filipa - - 2007
Den sites are a conspicuous feature of Eurasian badgers, Meles meles, and in many environments include large communal burrows used by several group members. In Serra de Grândola, southwest Portugal, nine badgers from three social groups were captured and radio collared from 2000 to 2004. A total of 1,787 locations ...
Abril S - - 2007
We analyzed the foraging activity and the dietary spectrum of the Argentine ant (Linepithema humile Mayr) and select native ants on cork oaks from Mediterranean open cork oak (Quercus suber) secondary forests. The study areas included invaded and noninvaded zones in close proximity. The Argentine ant's daily foraging activity was ...
de Kort Selvino R SR Department of Experimental Psychology, University of Cambridge, England. - - 2007
Western scrub-jays (Aphelocoma californica) did not show extinction when caching behavior was never rewarded and they had no choice of where to cache the food. However, when the jays had the choice of caching items in 2 different locations or during 2 successive episodes, and only 1 of each was ...
Crabbe Frederick L - - 2007
Among the many properties suggested for action-selection mechanisms, a prominent one is the ability to select compromise actions, i.e. actions that are not the best to satisfy any active goal in isolation, but rather compromise between multiple goals. This paper briefly reviews the history of compromise behaviour and presents experimental ...
Sanford Kirsten - - 2008
Remembering combinations of information such as what resources have been seen in which locations could play an important role in enhancing individual survival through increased foraging success. To date, there have been relatively few investigations of avian memory involving more than one category of information. This study explored zebra finches' ...
Doody Lesley M - - 2008
This study investigated how total corticosterone concentrations, chick-feeding rates, and adult body mass changed with food availability from 1998 to 2000 in the same individually marked common murres (Uria aalge). Capelin, the main prey species, arrived inshore by the onset of murre chick hatching in 1998 and 1999 (prey match ...
Yanagawa Aya - - 2008
Termites, Coptotermes formosanus Shiraki, reared individually, were highly susceptible to entomopathogenic fungi, Paecilomyces fumosoroseus and Beauveria brongniartii and Metarhizium anisopliae, while termites reared in groups were highly resistant. Quantitative assays with an epifluoresent microscope revealed a significant difference in the number of conidia attachments among three entomopathogenic fungi. The conidia ...
Spottiswoode Claire N - - 2007
Colony sizes in birds can vary by orders of magnitude within species, and many studies have shown that selection pressures differ dramatically among small and large colonies. Does such selection result in phenotypic sorting at the level of individuals? This study describes inter-colony differences in morphology and reproductive investment in ...
Joly Marine - - 2007
Field observations suggest that the diet of the Malagasy gray mouse lemur consists not only of non-stationary animal prey (invertebrates or small vertebrates), but also of stationary food resources such as gum or homopteran larvae secretions (HLS). We studied the foraging behavior of five mouse lemurs radiotelemetrically, each during six ...
Thom Corinna - - 2007
The waggle dance of honey bee (Apis mellifera L.) foragers communicates to nest mates the location of a profitable food source. We used solid-phase microextraction and gas chromatography coupled with mass spectrometry to show that waggle-dancing bees produce and release two alkanes, tricosane and pentacosane, and two alkenes, Z-(9)-tricosene and ...
Kunc Hansjoerg P - - 2007
In some species, dependent offspring join foraging providers and beg for food. Mobile offspring might benefit from evolving begging signals adapted to the different situations they are exposed to, but this possibility has been ignored. In cooperatively breeding meerkats (Suricata suricatta), dependent offspring use a repertoire of several begging calls ...
Urban Mark C - - 2007
Longstanding theory in behavioral ecology predicts that prey should evolve decreased foraging rates under high predation threat. However, an alternative perspective suggests that growth into a size refuge from gape-limited predation and the future benefits of large size can outweigh the initial survival costs of intense foraging. Here, I evaluate ...
White J Wilson - - 2007
Animals in social aggregations often spend more time foraging than solitary conspecifics. This may be a product of the relative safety afforded by aggregations: group members can devote more time to foraging and less time to antipredator behaviors than solitary animals (the "risk reduction" effect). All else being equal, risk ...
Inta Ra - - 2007
Drywood termites are able to assess wood size using vibratory signals, although the exact mechanism behind this assessment ability is not known. Important vibratory characteristics such as the modal frequencies of a wooden block depend on its geometry and boundary conditions; however, they are also dependent on the material characteristics ...
Laidre Mark E - - 2008
Although the technical problem-solving expertise of nonhuman primates has been investigated extensively in captivity, few species have been tested in their natural habitats. Here I examine the physical cognition of wild savanna baboons (Papio anubis), a species that occupies an omnivorous foraging niche in which a variety of embedded food ...
Beauchamp Guy - - 2007
I examined the effect of competitor density on foraging success in staging semipalmated sandpipers (Calidris pusilla) foraging on a burrowing amphipod (Corophium volutator) in each of two study years. Little is known about the effect of competitor density when predation attempts disturb prey, causing a temporary decrease in food availability. ...
Harding Ann M A - - 2007
Flexible time budgets allow individual animals to buffer the effects of variable food availability by allocating more time to foraging when food density decreases. This trait should be especially important for marine predators that forage on patchy and ephemeral food resources. We examined flexible time allocation by a long-lived marine ...
Beauchamp Guy - - 2007
I examined the role of vision in social foraging by contrasting group size, vigilance, spacing, aggression and habitat use between day and night in many species of birds and mammals. The literature review revealed that the rate of predation/disturbance was often reduced at night while food was considered more available. ...
Reynolds Andrew M - - 2007
Honey bees (Apis mellifera) are regularly faced with the task of navigating back to their hives from remote food sources. They have evolved several methods to do this, including compass-directed "vector" flights and the use of landmarks. If these hive-centered mechanisms are disrupted, bees revert to searching for the hive, ...
Dapporto Leonardo - - 2007
Differences in long-chain hydrocarbon mixtures among reproductive and nonreproductive individuals have been often revealed in social insects. However, very few papers demonstrated that these signatures actually act as contact pheromones used by nonreproductive to recognize the presence of a related queen in the colony. Cuticular and glandular hydrocarbons of Polistes ...
Schatz Greg S - - 2007
Mismatches in the elemental composition of herbivores and their resources can impact herbivore growth and reproduction. In aquatic systems, the ratio of elements, such as C, P, and N, is used to characterize the food quality of algal prey. For example, large increases in the C:P ratio of edible algae ...
Lee Sang-Hee - - 2008
Subterranean termites construct underground tunnels, tens to hundreds of feet, to reach feeding sites and to transport food items to their nest. To ensure a high rate food return to the nest, an optimized tunnel should be constructed. We found that termites (Coptotermes formosanus Shiraki) fill the corner of a ...
Matsuura, Makoto
The present study aims to clarify the specific difference in bionomic characters of the five Japanese <special>Vespa</special> species, <special>V. simillima xanthoptera CAMERON</special>, <special>V. analis insularis DALLA TORRE</special>, <special>V. crabro flavofasciata CAMERON</special>, <special>V. mandarinia japonica RADOSZKOWSKI</special> and <special>V. tropica pulchra BUYSSON</special>, which coexist in low mountain areas of southwestJapan. The life ...
Pienaar, JP; ;
Sheep were used in two investigations to study factors which could limit voluntary intake of <i>Pennisetum clandestinum</i> (kikuyu) pasture. Possible reasons for the low intakes were found in the high soluble nitrogen and nitrate content of the pasture, its high oxalate content, and its considerable potential for foaming, the latter ...
Killen Shaun S - - 2007
1. In many species, individuals will alter their foraging strategy in response to changes in prey density. However, previous work has shown that prey density has differing effects on the foraging mode decisions of ectotherms as compared with endotherms. This is likely due to differences in metabolic demand; however, the ...
Janson Charles H - - 2007
Both in captivity and the wild, primates are found to travel mostly to the nearest available resource, but they may skip over the closest resource and travel to more distant resources, which are often found to be more productive. This study examines the tradeoff between distance and reward in the ...
Molokwu, Mary Ngozi; AP ...
Using the density of food left in a patch after foraging — i.e. the giving-up density (GUD) — as a behavioural indicator, shortterm foraging studies on birds in the dry and wet fringing forests and savanna habitats of the Amurum Forest Reserve, Laminga, Nigeria, were used to evaluate whether widespread ...
Sulikowski Danielle - - 2007
The tendency of nectarivorous birds to perform better on tasks requiring them to avoid previously rewarding locations (to win-shift) than to return to them (win-stay) has been explained as an adaptation to the depleting nature of nectar. This interpretation relies on the previously untested assumption that the win-shift tendency is ...
Schloegl Christian - - 2008
Most animals seem to have difficulties in using gaze cues to find hidden food in object-choice tasks. For instance, chimpanzees usually fail in these tests, even though they are capable of following other's gaze geometrically behind barriers. Similar to chimpanzees, common ravens are skilled in tracking other's gaze but fail ...
LaPierre Louis - - 2007
Food robbing, or cleptobiosis, has been well documented throughout the animal kingdom. For insects, intrafamilial food robbing is known among ants, but social wasps (Vespidae; Polistinae) taking food from ants has, to the best of our knowledge, never been reported. In this paper, we present two cases involving social wasps ...
Yeates Laura C - - 2007
As the smallest and one of the most recently evolved marine mammals, sea otters face physiological challenges rarely encountered by larger, more derived aquatic species. To examine the effect of these challenges on foraging costs and resultant daily energy budgets, we measured the energetics of resting, grooming, diving and foraging ...
Graham Paul - - 2007
Insects can guide themselves along a familiar route to a familiar place by retrieving and using visual snapshots that they have stored both along the route and at their destination and moving so that their current views match the target snapshots. To learn more about the matching process, we have ...
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