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Author Cameron, E.Z.; du Toit, J.T. doi  openurl
  Title (down) Winning by a neck: tall giraffes avoid competing with shorter browsers Type Journal Article
  Year 2007 Publication The American naturalist Abbreviated Journal Am Nat  
  Volume 169 Issue 1 Pages 130-135  
  Keywords Acacia/growth & development; Animals; Feeding Behavior/*physiology; Neck/*anatomy & histology; Plant Leaves/growth & development; Ruminants/*anatomy & histology/*physiology; South Africa  
  Abstract With their vertically elongated body form, giraffes generally feed above the level of other browsers within the savanna browsing guild, despite having access to foliage at lower levels. They ingest more leaf mass per bite when foraging high in the tree, perhaps because smaller, more selective browsers deplete shoots at lower levels or because trees differentially allocate resources to promote shoot growth in the upper canopy. We erected exclosures around individual Acacia nigrescens trees in the greater Kruger ecosystem, South Africa. After a complete growing season, we found no differences in leaf biomass per shoot across height zones in excluded trees but significant differences in control trees. We conclude that giraffes preferentially browse at high levels in the canopy to avoid competition with smaller browsers. Our findings are analogous with those from studies of grazing guilds and demonstrate that resource partitioning can be driven by competition when smaller foragers displace larger foragers from shared resources. This provides the first experimental support for the classic evolutionary hypothesis that vertical elongation of the giraffe body is an outcome of competition within the browsing ungulate guild.  
  Address Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa. ezcameron@zoology.up.ac.za  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1537-5323 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17206591 Approved no  
  Call Number refbase @ user @ Serial 410  
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Author Lonsdorf, E.V. doi  openurl
  Title (down) What is the role of mothers in the acquisition of termite-fishing behaviors in wild chimpanzees (Pan troglodytes schweinfurthii)? Type Journal Article
  Year 2006 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 9 Issue 1 Pages 36-46  
  Keywords Animals; Animals, Wild; *Behavior, Animal; Cooking and Eating Utensils; Feeding Behavior/*psychology; Female; *Imitative Behavior; Learning; Mothers/*psychology; Motor Skills; Pan troglodytes/*psychology; Problem Solving  
  Abstract This paper explores the role of maternal influences on the acquisition of a tool-using task in wild chimpanzees (Pan troglodytes schweinfurthii) in order to build on and complement previous work done in captivity. Young chimpanzees show a long period of offspring dependency on mothers and it is during this period that offspring learn several important skills, especially how to and on what to forage. At Gombe National Park, one skill that is acquired during dependency is termite-fishing, a complex behavior that involves inserting a tool made from the surrounding vegetation into a termite mound and extracting the termites that attack and cling to the tool. All chimpanzees observed at Gombe have acquired the termite-fishing skill by the age of 5.5 years. Since the mother is the primary source of information throughout this time period, I investigated the influence of mothers' individual termite-fishing characteristics on their offsprings' speed of acquisition and proficiency at the skill once acquired. Mother's time spent alone or with maternal family members, which is highly correlated to time spent termite-fishing, was positively correlated to offspring's acquisition of critical elements of the skill. I also investigated the specific types of social interactions that occur between mothers and offspring at the termite mound and found that mothers are highly tolerant to offspring, even when the behavior of the offspring may disrupt the termite-fishing attempt. However, no active facilitation by mothers of offsprings' attempts were observed.  
  Address Department of Ecology, Evolution and Behavior, University of Minnesota, St. Paul, MN 55108, USA. elonsdorf@lpzoo.org  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16195914 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2480  
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Author Emery, N.J.; Dally, J.M.; Clayton, N.S. doi  openurl
  Title (down) Western scrub-jays ( Aphelocoma californica) use cognitive strategies to protect their caches from thieving conspecifics Type Journal Article
  Year 2004 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 7 Issue 1 Pages 37-43  
  Keywords Animals; Birds/*physiology; Feeding Behavior/*physiology; Female; *Food; Male; *Memory  
  Abstract Food caching birds hide food and recover the caches when supplies are less abundant. There is, however, a risk to this strategy because the caches are susceptible to pilfering by others. Corvids use a number of different strategies to reduce possible cache theft. Scrub-jays with previous experience of pilfering other's caches cached worms in two visuospatially distinct caching trays either in private or in the presence of a conspecific. When these storers had cached in private, they subsequently observed both trays out of reach of a conspecific. When these storers had cached in the presence of a conspecific, they subsequently watched the observer pilfering from one of the trays while the other tray was placed in full view, but out of reach. The storers were then allowed to recover the remaining caches 3 h later. Jays cached more worms when they were observed during caching. At the time of recovery, they re-cached more than if they had cached in private, selectively re-caching outside of the trays in sites unbeknown to potential thieves. In addition, after a single pilfering trial, the jays switched their recovery strategy from predominantly checking their caches (i.e. returning to a cache site to see whether the food remained there) to predominantly eating them. Re-caching remained constant across the three trials. These results suggest that scrub-jays use flexible, cognitive caching and recovery strategies to aid in reducing potential future pilfering of caches by conspecifics.  
  Address Sub-department of Animal Behaviour, University of Cambridge, High Street, CB3 8AA Madingley, Cambs, UK. nje23@cam.ac.uk  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12827547 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2566  
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Author Ottoni, E.B.; de Resende, B.D.; Izar, P. doi  openurl
  Title (down) Watching the best nutcrackers: what capuchin monkeys (Cebus apella) know about others' tool-using skills Type Journal Article
  Year 2005 Publication Animal cognition Abbreviated Journal Anim. Cogn.  
  Volume 8 Issue 4 Pages 215-219  
  Keywords Animals; *Association Learning; Cebus/*psychology; *Feeding Behavior; Female; Male; Nuts; *Problem Solving  
  Abstract The present work is part of a decade-long study on the spontaneous use of stones for cracking hard-shelled nuts by a semi-free-ranging group of brown capuchin monkeys (Cebus apella). Nutcracking events are frequently watched by other individuals--usually younger, less proficient, and that are well tolerated to the point of some scrounging being allowed by the nutcracker. Here we report findings showing that the choice of observational targets is an active, non-random process, and that observers seem to have some understanding of the relative proficiency of their group mates, preferentially watching the more skilled nutcrackers, which enhances not only scrounging payoffs, but also social learning opportunities.  
  Address Laboratory of Cognitive Ethology, Department of Experimental Psychology, Institute of Psychology, University of Sao Paulo, Brazil. ebottoni@usp.br  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15719240 Approved no  
  Call Number refbase @ user @ Serial 355  
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Author Ordakowski-Burk, A.L.; Quinn, R.W.; Shellem, T.A.; Vough, L.R. doi  openurl
  Title (down) Voluntary intake and digestibility of reed canarygrass and timothy hay fed to horses Type Journal Article
  Year 2006 Publication Journal of Animal Science Abbreviated Journal J. Anim Sci.  
  Volume 84 Issue 11 Pages 3104-3109  
  Keywords Animal Feed/*analysis; Animal Nutrition Physiology; Animals; Diet/*veterinary; Digestion/*physiology; Feeding Behavior/*physiology; Horses/*physiology; Male; Poaceae/*metabolism  
  Abstract Thousands of hectares of timothy (Phleum pretense L.) grown in the Mid-Atlantic region are infected by cereal rust mite (Abacarus hysterix) that causes discoloration and curling of leaves, decreased nutritional quality, and substantial decreases in yield. A decline in production of timothy hay can lower income for hay producers and cause horse owners to search for alternative hays. Low alkaloid reed canarygrass (Phalaris arundinacea L.) hay has potential as an alternative to timothy hay because it grows well in the Mid-Atlantic region, is believed to have a similar nutrient quality to timothy, and is not as susceptible to cereal rust mite. Eleven mature, stalled Thoroughbred geldings (549 +/- 12.1 kg) that were exercised daily were used to compare voluntary DMI and apparent nutrient DM digestibility of timothy and low-alkaloid Chiefton variety reed canarygrass hay. Horses were paired by age and BW and randomly assigned to timothy or reed canarygrass hay during a 14-d period to measure voluntary DMI followed by a 4-d period to measure apparent DM digestibility. Both hays met the minimum requirements for DE, CP, Ca, P, K, Fe, and Mn, but they did not meet the minimum requirements for Cu, Zn, and Na for horses at maintenance and averaging 550 kg of BW. Timothy hay seemed to have a lower CP concentration (14.4%) compared with reed canarygrass hay (17.1%) and a more desirable Ca:P ratio at 1.6:1 compared with 0.8:1 for reed canarygrass hay. Horses fed timothy consumed more hay (P <0.001) during the voluntary DMI period compared with horses fed reed canarygrass. Greater voluntary DMI of timothy occurred on d 1, 3, and 5 (P <0.05), but DMI was similar for other days. Apparent DM digestibility was greater in horses fed timothy hay by 9.6% compared with horses fed reed canarygrass hay (P <0.05). Horses fed timothy had greater DM digestibility of ADF (P = 0.001), NDF (P = 0.001), sugar (P = 0.05), and Ca (P = 0.001) but lower apparent DM digestibility of CP (P = 0.012) and crude fat (P = 0.004). Timothy hay was superior in voluntary DMI and apparent DM digestibility compared with low-alkaloid reed canarygrass hay fed to horses.  
  Address Department of Animal and Avian Sciences, University of Maryland, College Park 20742, USA. amyburk@umd.edu  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1525-3163 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17032805 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4236  
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Author De Stoppelaire, G.H.; Gillespie, T.W.; Brock, J.C.; Tobin, G.A. doi  openurl
  Title (down) Use of remote sensing techniques to determine the effects of grazing on vegetation cover and dune elevation at Assateague Island National Seashore: impact of horses Type Journal Article
  Year 2004 Publication Environmental Management Abbreviated Journal Environ Manage  
  Volume 34 Issue 5 Pages 642-649  
  Keywords Animals; Animals, Wild; Conservation of Natural Resources; Ecosystem; Environmental Monitoring; *Feeding Behavior; *Horses; Maryland; Plants/*growth & development; Population Dynamics; Silicon Dioxide; *Soil  
  Abstract The effects of grazing by feral horses on vegetation and dune topography at Assateague Island National Seashore were investigated using color-infrared imagery, lidar surveys, and field measurements. Five pairs of fenced and unfenced plots (300 m2) established in 1993 on sand flats and small dunes with similar elevation, topography, and vegetation cover were used for this study. Color-infrared imagery from 1998 and field measurements from 2001 indicated that there was a significant difference in vegetation cover between the fenced and unfenced plot-pairs over the study period. Fenced plots contained a higher percentage of vegetation cover that was dominated by American beachgrass (Ammophila breviligulata). Lidar surveys from 1997, 1999, and 2000 showed that there were significant differences in elevation and topography between fenced and unfenced plot-pairs. Fenced plots were, on average, 0.63 m higher than unfenced plots, whereas unfenced plots had generally decreased in elevation after establishment in 1993. Results demonstrate that feral horse grazing has had a significant impact on dune formation and has contributed to the erosion of dunes at Assateague Island. The findings suggest that unless the size of the feral horse population is reduced, grazing will continue to foster unnaturally high rates of dune erosion into the future. In order to maintain the natural processes that historically occurred on barrier islands, much larger fenced exclosures would be required to prevent horse grazing.  
  Address US Geological Survey, Center for Coastal and Watershed Studies, St. Petersburg, Florida 33701, USA. georgia.destoppelaire@my.FWC.com  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0364-152X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15633024 Approved no  
  Call Number Serial 1896  
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Author van Heel, M.C.V.; Kroekenstoel, A.M.; van Dierendonck, M.C.; van Weeren, P.R.; Back, W. openurl 
  Title (down) Uneven feet in a foal may develop as a consequence of lateral grazing behaviour induced by conformational traits Type Journal Article
  Year 2006 Publication Equine veterinary journal Abbreviated Journal Equine. Vet. J.  
  Volume 38 Issue 7 Pages 646-651  
  Keywords Aging/*physiology; Animals; Animals, Newborn/anatomy & histology/growth & development/physiology; Feeding Behavior/*physiology; Female; Forelimb/*anatomy & histology/*physiology; *Horses/anatomy & histology/growth & development/physiology; Male  
  Abstract REASONS FOR PERFORMING STUDY: Conformational traits are important in breeding, since they may be indicative for performance ability and susceptibility to injuries. OBJECTIVES: To study whether certain desired conformational traits of foals are related to lateralised behaviour while foraging and to the development of uneven feet. METHODS: Twenty-four Warmblood foals, born and raised at the same location, were studied for a year. Foraging behaviour was observed by means of weekly 10 min scan-sampling for 8 h. A preference test (PT) was developed to serve as a standardised tool to determine laterality. The foals were evaluated at age 3, 15, 27 and 55 weeks. The PT and distal limb conformation were used to study the relation between overall body conformation, laterality and the development of uneven feet. Pressure measurements were used to determine the loading patterns under the feet. RESULTS: About 50% of the foals developed a significant preference to protract the same limb systematically while grazing, which resulted in uneven feet and subsequently uneven loading patterns. Foals with relatively long limbs and small heads were predisposed to develop laterality and, consequently unevenness. CONCLUSIONS: Conformational traits may stimulate the development of laterality and therefore indirectly cause uneven feet.  
  Address Derona Equine Performance Laboratory, Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 12, NL-3584 CM Utrecht, The Netherlands  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0425-1644 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17228580 Approved no  
  Call Number Serial 1774  
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Author Kuroshima, H.; Fujita, K.; Fuyuki, A.; Masuda, T. doi  openurl
  Title (down) Understanding of the relationship between seeing and knowing by tufted capuchin monkeys (Cebus apella) Type Journal Article
  Year 2002 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 5 Issue 1 Pages 41-48  
  Keywords Adaptation, Psychological; Animals; Cebus/*psychology; *Discrimination (Psychology); Feeding Behavior/*psychology; Female; Male  
  Abstract The ability of four tufted capuchin monkeys (Cebus apella) to recognize the causal connection between seeing and knowing was investigated. The subjects were trained to follow a suggestion about the location of hidden food provided by a trainer who knew where the food was (the knower) in preference to a trainer who did not (the guesser). The experimenter baited one of three opaque containers behind a cardboard screen so that the subjects could not see which of the containers hid the reward. In experiment 1, the knower appeared first in front of the apparatus and looked into each container; next, the guesser appeared but did not look into any containers. Then the knower touched the correct cup while the guesser touched one of the three randomly. The capuchin monkeys gradually learned to reach toward the cup that the knower suggested. In experiment 2, the subjects adapted to a novel variant of the task, in which the guesser touched but did not look into any of the containers. In experiment 3, the monkeys adapted again when the knower and the guesser appeared in a random order. These results suggest that capuchin monkeys can learn to recognize the relationship between seeing and knowing.  
  Address Department of Psychology, Graduate School of Letters, Kyoto University, Yoshida-honmachi, Sakyo, Kyoto, 606-8501, Japan. kuroshi@psy.bun.kyoto-u.ac.jp  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:11957401 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2611  
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Author Cleveland, A.; Rocca, A.M.; Wendt, E.L.; Westergaard, G.C. doi  openurl
  Title (down) Transport of tools to food sites in tufted capuchin monkeys (Cebus apella) Type Journal Article
  Year 2004 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 7 Issue 3 Pages 193-198  
  Keywords Animals; *Association Learning; Cebus/*psychology; *Concept Formation; *Feeding Behavior; Female; Male; *Problem Solving  
  Abstract Tool use and transport represent cognitively important aspects of early hominid evolution, and nonhuman primates are often used as models to examine the cognitive, ecological, morphological and social correlates of these behaviors in order to gain insights into the behavior of our early human ancestors. In 2001, Jalles-Filho et al. found that free-ranging capuchin monkeys failed to transport tools (stones) to food sites (nuts), but transported the foods to the tool sites. This result cast doubt on the usefulness of Cebus to model early human tool-using behavior. In this study, we examined the performance of six captive tufted capuchin monkeys (Cebus apella) in a tool transport task. Subjects were provided with the opportunity to transport two different tools to fixed food reward sites when the food reward was visible from the tool site and when the food reward was not visible from the tool site. We found that the subjects quickly and readily transported probing tools to an apparatus baited with syrup, but rarely transported stones to a nut-cracking apparatus. We suggest that the performance of the capuchins here reflects an efficient foraging strategy, in terms of energy return, among wild Cebus monkeys.  
  Address Alpha Genesis, 95 Castle Hall Road, P.O. Box 557, Yemassee, SC 29945, USA  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15022055 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2539  
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Author Sterling, E.J.; Povinelli, D.J. openurl 
  Title (down) Tool use, aye-ayes, and sensorimotor intelligence Type Journal Article
  Year 1999 Publication Folia Primatologica; International Journal of Primatology Abbreviated Journal Folia Primatol (Basel)  
  Volume 70 Issue 1 Pages 8-16  
  Keywords Animals; *Behavior, Animal; Feeding Behavior; Female; *Intelligence; Male; Problem Solving; *Psychomotor Performance; Strepsirhini/*physiology/psychology  
  Abstract Humans, chimpanzees, capuchins and aye-ayes all display an unusually high degree of encephalization and diverse omnivorous extractive foraging. It has been suggested that the high degree of encephalization in aye-ayes may be the result of their diverse, omnivorous extractive foraging behaviors. In combination with certain forms of tool use, omnivorous extractive foraging has been hypothesized to be linked to higher levels of sensorimotor intelligence (stages 5 or 6). Although free-ranging aye-ayes have not been observed to use tools directly in the context of their extractive foraging activities, they have recently been reported to use lianas as tools in a manner that independently suggests that they may possess stage 5 or 6 sensorimotor intelligence. Although other primate species which display diverse, omnivorous extractive foraging have been tested for sensorimotor intelligence, aye-ayes have not. We report a test of captive aye-ayes' comprehension of tool use in a situation designed to simulate natural conditions. The results support the view that aye-ayes do not achieve stage 6 comprehension of tool use, but rather may use trial-and-error learning to develop tool-use behaviors. Other theories for aye-aye encephalization are considered.  
  Address Deutsches Primatenzentrum, Gottingen, Germany  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0015-5713 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:10050062 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4178  
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