| |
Records |
Links |
|
Author |
Bobbert, M.F.; Santamaria, S. |
|
| |
Title |
Contribution of the forelimbs and hindlimbs of the horse to mechanical energy changes in jumping |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
The Journal of Experimental Biology |
Abbreviated Journal |
J Exp Biol |
|
| |
Volume |
208 |
Issue |
2 |
Pages |
249-260 |
|
| |
Keywords |
Animals; Biomechanics; Forelimb/*physiology; Hindlimb/*physiology; Horses/*physiology; Locomotion/*physiology; Muscle, Skeletal/*physiology; Time Factors |
|
| |
Abstract |
The purpose of the present study was to gain more insight into the contribution of the forelimbs and hindlimbs of the horse to energy changes during the push-off for a jump. For this purpose, we collected kinematic data at 240 Hz from 23 5-year-old Warmbloods (average mass: 595 kg) performing free jumps over a 1.15 m high fence. From these data, we calculated the changes in mechanical energy and the changes in limb length and joint angles. The force carried by the forelimbs and the amount of energy stored was estimated from the distance between elbow and hoof, assuming that this part of the leg behaved as a linear spring. During the forelimb push, the total energy first decreased by 3.2 J kg(-1) and then increased again by 4.2 J kg(-1) to the end of the forelimb push. At the end of the forelimb push, the kinetic energy due to horizontal velocity of the centre of mass was 1.6 J kg(-1) less than at the start, while the effective energy (energy contributing to jump height) was 2.3 J kg(-1) greater. It was investigated to what extent these changes could involve passive spring-like behaviour of the forelimbs. The amount of energy stored and re-utilized in the distal tendons during the forelimb push was estimated to be on average 0.4 J kg(-1) in the trailing forelimb and 0.23 J kg(-1) in the leading forelimb. This means that a considerable amount of energy was first dissipated and subsequently regenerated by muscles, with triceps brachii probably being the most important contributor. During the hindlimb push, the muscles of the leg were primarily producing energy. The total increase in energy was 2.5 J kg(-1) and the peak power output amounted to 71 W kg(-1). |
|
| |
Address |
Institute for Fundamental and Clinical Human Movement Sciences, Vrije Universiteit, van der Boechorstraat 9, NL-1081 BT Amsterdam, The Netherlands. MFBobbert@fbw.vu.nl |
|
| |
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 |
0022-0949 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15634844 |
Approved |
no |
|
| |
Call Number  |
|
Serial |
1895 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Robert, N.; Walzer, C.; Ruegg, S.R.; Kaczensky, P.; Ganbaatar, O.; Stauffer, C. |
|
| |
Title |
Pathologic findings in reintroduced Przewalski's horses (Equus caballus przewalskii) in southwestern Mongolia |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Journal of zoo and Wildlife Medicine : Official Publication of the American Association of Zoo Veterinarians |
Abbreviated Journal |
J Zoo Wildl Med |
|
| |
Volume |
36 |
Issue |
2 |
Pages |
273-285 |
|
| |
Keywords |
Animals; Babesiosis/epidemiology/pathology/*veterinary; Cause of Death; Conservation of Natural Resources; Disease Susceptibility/veterinary; Environment; Female; Food Chain; Horse Diseases/*epidemiology/pathology; Horses; Male; Mongolia/epidemiology; Streptococcal Infections/epidemiology/pathology/*veterinary; *Streptococcus equi; Theileriasis/*epidemiology/pathology; Weather |
|
| |
Abstract |
The Przewalski's horse (Equus caballus przewalskii) was extinct in the wild by the mid 1960s. The species has survived because of captive breeding only. The Takhin Tal reintroduction project is run by the International Takhi Group; it is one of two projects reintroducing horses to the wild in Mongolia. In 1997 the first harem group was released. The first foals were successfully raised in the wild in 1999. Currently, 63 Przewalski's horses live in Takhin Tal. Little information exists on causes of mortality before the implementation of a disease-monitoring program in 1998. Since 1999, all dead horses recovered (n = 28) have been examined and samples collected and submitted for further investigation. Equine piroplasmosis, a tick-transmitted disease caused by Babesia caballi or Theileria equi, is endemic in Takhin Tal and was identified as the cause of death of four stallions and one stillborn foal. In December 2000, wolf predation was implicated in the loss of several Przewalski's horses. However, thorough clinical, pathologic, and bacteriologic investigations performed on dead and surviving horses of this group revealed lesions compatible with strangles. The extreme Mongolian winter of 2000-2001 is thought to have most probably weakened the horses, making them more susceptible to opportunistic infection and subsequent wolf predation. Other occasional causes of death since 1999 were trauma, exhaustion, wasting, urolithiasis, pneumonia, abortion, and stillbirth. The pathologic examination of the Przewalski's horses did not result in a definitive diagnosis in each case. Several disease factors were found to be important in the initial phase of the reintroduction, which could potentially jeopardize the establishment of a self-sustaining population. |
|
| |
Address |
Center for Fish and Wildlife Health, Institute of Animal Pathology, University of Berne, Langgass-Strasse 122, CH-3001 Berne, Switzerland |
|
| |
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 |
1042-7260 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:17323569 |
Approved |
no |
|
| |
Call Number |
|
Serial |
2023 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Dall, S.R.X.; Giraldeau, L.-A.; Olsson, O.; McNamara, J.M.; Stephens, D.W. |
|
| |
Title |
Information and its use by animals in evolutionary ecology |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Trends in Ecology & Evolution (Personal Edition) |
Abbreviated Journal |
Trends Ecol Evol |
|
| |
Volume |
20 |
Issue |
4 |
Pages |
187-193 |
|
| |
Keywords |
|
|
| |
Abstract |
Information is a crucial currency for animals from both a behavioural and evolutionary perspective. Adaptive behaviour relies upon accurate estimation of relevant ecological parameters; the better informed an individual, the better it can develop and adjust its behaviour to meet the demands of a variable world. Here, we focus on the burgeoning interest in the impact of ecological uncertainty on adaptation, and the means by which it can be reduced by gathering information, from both 'passive' and 'responsive' sources. Our overview demonstrates the value of adopting an explicitly informational approach, and highlights the components that one needs to develop useful approaches to studying information use by animals. We propose a quantitative framework, based on statistical decision theory, for analysing animal information use in evolutionary ecology. Our purpose is to promote an integrative approach to studying information use by animals, which is itself integral to adaptive animal behaviour and organismal biology. |
|
| |
Address |
Centre for Ecology and Conservation, University of Exeter in Cornwall, Tremough Campus, Penryn, UK, TR10 9EZ. sashadall@iname.com |
|
| |
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 |
0169-5347 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:16701367 |
Approved |
no |
|
| |
Call Number |
|
Serial |
2128 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Barrett, L.; Henzi, P. |
|
| |
Title |
The social nature of primate cognition |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Proceedings. Biological Sciences / The Royal Society |
Abbreviated Journal |
Proc Biol Sci |
|
| |
Volume |
272 |
Issue |
1575 |
Pages |
1865-1875 |
|
| |
Keywords |
Animals; Brain/anatomy & histology/*physiology; Cognition/*physiology; *Evolution; Intelligence/*physiology; Primates/*physiology; *Social Behavior |
|
| |
Abstract |
The hypothesis that the enlarged brain size of the primates was selected for by social, rather than purely ecological, factors has been strongly influential in studies of primate cognition and behaviour over the past two decades. However, the Machiavellian intelligence hypothesis, also known as the social brain hypothesis, tends to emphasize certain traits and behaviours, like exploitation and deception, at the expense of others, such as tolerance and behavioural coordination, and therefore presents only one view of how social life may shape cognition. This review outlines work from other relevant disciplines, including evolutionary economics, cognitive science and neurophysiology, to illustrate how these can be used to build a more general theoretical framework, incorporating notions of embodied and distributed cognition, in which to situate questions concerning the evolution of primate social cognition. |
|
| |
Address |
School of Biological Sciences, University of Liverpool, Crown Street, Liverpool L69 7ZB, UK. louiseb@liv.ac.uk |
|
| |
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 |
0962-8452 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:16191591 |
Approved |
no |
|
| |
Call Number |
|
Serial |
2086 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Dunbar, R.I.M.; McAdam, M.R.; O'connell, S. |
|
| |
Title |
Mental rehearsal in great apes (Pan troglodytes and Pongo pygmaeus) and children |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Behavioural Processes |
Abbreviated Journal |
Behav. Process. |
|
| |
Volume |
69 |
Issue |
3 |
Pages |
323-330 |
|
| |
Keywords |
Algorithms; Animals; Child; Child, Preschool; Food; Frontal Lobe/anatomy & histology/physiology; Humans; *Imagination; Pan troglodytes; Pongo pygmaeus; Problem Solving/*physiology; Psychomotor Performance/physiology; Reward |
|
| |
Abstract |
The ability to rehearse possible future courses of action in the mind is an important feature of advanced social cognition in humans, and the “social brain” hypothesis implies that it might also be a feature of primate social cognition. We tested two chimpanzees, six orangutans and 63 children aged 3-7 years on a set of four puzzle boxes, half of which were presented with an opportunity to observe the box before being allowed to open it (“prior view”), the others being given without an opportunity to examine the boxes before handling them (“no prior view”). When learning effects are partialled out, puzzle boxes in the “prior view” condition were opened significantly faster than boxes given in the “no prior view” condition by the children, but not by either of the great apes. The three species differ significantly in the speed with which they opened boxes in the “no prior view” condition. The three species' performance on this task was a function of relative frontal lobe volume, suggesting that it may be possible to identify quantitative neuropsychological differences between species. |
|
| |
Address |
Evolutionary Psychology Research Group, School of Biological Sciences, University of Liverpool, Biosciences Building, Crown Street, Liverpool L69 7ZB, UK. rimd@liv.ac.uk |
|
| |
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 |
0376-6357 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15896530 |
Approved |
no |
|
| |
Call Number |
|
Serial |
2097 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Pompilio, L.; Kacelnik, A. |
|
| |
Title |
State-dependent learning and suboptimal choice: when starlings prefer long over short delays to food |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Animal Behaviour. |
Abbreviated Journal |
Anim. Behav. |
|
| |
Volume |
70 |
Issue |
3 |
Pages |
571-578 |
|
| |
Keywords |
|
|
| |
Abstract |
Recent studies have used labels such as `work ethics', `sunk costs' and `state-dependent preferences' for apparent anomalies in animals' choices. They suggest that preference between options relates to the options' history, rather than depending exclusively on the expected payoffs. For instance, European starlings, Sturnus vulgaris, trained to obtain identical food rewards from two sources while in two levels of hunger preferred the food source previously associated with higher hunger, regardless of the birds' state at the time of testing. We extended this experimentally and theoretically by studying starlings choosing between sources that differed not only in history but also in the objective properties (delay until reward) of the payoffs they delivered. Two options (PF and H) were initially presented in single-option sessions when subjects were, respectively, prefed or hungry. While option PF offered a delay until reward of 10 s in all treatments, option H delivered delays of 10, 12.5, 15 and 17.5 s in four treatments. When training was completed, we tested preference between the options. When delays in both options were equal (10 s), the birds strongly preferred H. When delay in H was 17.5 s, the birds were indifferent, with intermediate results for intermediate treatments. Preference was not mediated by disrupted knowledge of the delays. Thus, preferences were driven by past state-dependent gains, rather than by the joint effect of the birds' state at the time of choice and knowledge of the absolute properties of each alternative, as assumed in state-dependent, path-independent models of optimal choice. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
|
Serial |
2104 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Fernández-Juricic,E.; Smith, R.; Kacelnik,A. |
|
| |
Title |
Increasing the costs of conspecific scanning in socially foraging starlings affects vigilance and foraging behaviour |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Animal Behaviour. |
Abbreviated Journal |
Anim. Behav. |
|
| |
Volume |
69 |
Issue |
1 |
Pages |
73-81 |
|
| |
Keywords |
|
|
| |
Abstract |
Social foragers receive and use information both about companions (social information) and about events external to the group, such as presence of potential predators. Scanning behaviour is often incorporated in theoretical models using simplifying assumptions in relation to the trade-off in information gathering between body postures (head-up versus head-down); however, some avian visual systems may allow individuals to scan in both body postures. We studied these issues experimentally, using starlings, Sturnus vulgaris, foraging in enclosures on natural fields. We varied the availability of information from conspecifics by placing visual barriers that blocked the view when the subjects were in head-down position and by manipulating the distance between group members. We found that as social information was reduced, starlings spent more time scanning (on and off the ground) and head-up scanning was mainly oriented towards conspecifics. The visual-obstruction effects imply that some information about conspecifics is normally gathered while starlings are foraging head-down. Neighbour distance and visual obstruction negatively affected food-searching rates and intake rates in two ways: (1) the effect of obstruction was mediated mostly through time competition between foraging and scanning on the ground, and (2) the effect of distance was due to a reduction in the rate of prey returns per searching effort while the birds were head-down. We conclude that the head-up posture is only one component of scanning, that the effects of head-down scanning should also be considered in species with ample visual fields, and that scanning in starlings is strongly connected to monitoring other flock members. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
|
Serial |
2105 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Kendal, R.L.; Coe, R.L.; Laland, K.N. |
|
| |
Title |
Age differences in neophilia, exploration, and innovation in family groups of callitrichid monkeys |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
American journal of primatology |
Abbreviated Journal |
Am. J. Primatol. |
|
| |
Volume |
66 |
Issue |
2 |
Pages |
167-188 |
|
| |
Keywords |
Age Factors; Analysis of Variance; Animals; *Animals, Zoo; Behavior, Animal/*physiology; Callitrichinae/*physiology; *Creativeness; Exploratory Behavior/*physiology; Observation; Social Behavior; Task Performance and Analysis |
|
| |
Abstract |
The prevailing assumption in the primate literature is that young or juvenile primates are more innovative than adult individuals. This innovative tendency among the young is frequently thought to be a consequence, or side effect, of their increased rates of exploration and play. Conversely, Reader and Laland's [International Journal of Primatology 22:787-806, 2001] review of the primate innovation literature noted a greater reported incidence of innovation in adults than nonadults, which they interpreted as (in part) a reflection of the greater experience and competence of older individuals. Within callitrichids there is contradictory evidence for age differences in response to novel objects, foods, and foraging tasks. By presenting novel extractive foraging tasks to family groups of callitrichid monkeys in zoos, we examined, in a large sample, whether there are positive or negative relationships of age with neophilia, exploration, and innovation, and whether play or experience most facilitates innovation. The results indicate that exploration and innovation (but not neophilia) are positively correlated with age, perhaps reflecting adults' greater manipulative competence. To the extent that there was evidence for play in younger individuals, it did not appear to contribute to innovation. The implications of these findings for the fields of innovation and conservation through reintroduction are considered. |
|
| |
Address |
Sub-Department of Animal Behavior, University of Cambridge, Cambridge, UK. RachelKendal2003@yahoo.co.uk |
|
| |
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 |
0275-2565 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:15940712 |
Approved |
no |
|
| |
Call Number |
|
Serial |
2148 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
NICOLA J. ROONEY & JOHN W. S. BRADSHAW |
|
| |
Title |
Social cognition in the domestic dog: behaviour of spectators towards participants in interspecific games |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Animal Behaviour. |
Abbreviated Journal |
Anim. Behav. |
|
| |
Volume |
72 |
Issue |
2 |
Pages |
343-352 |
|
| |
Keywords |
|
|
| |
Abstract |
previous termSocial cognition,next term in particular the derivation of previous termsocialnext term information from observation of interactions between members of a previous termsocialnext term group, has been widely investigated in primates, but it has received little attention in other previous termsocialnext term mammals, although it has been anecdotally reported in the previous termdomestic dog,next term Canis familiaris. We recorded the behaviour of previous termdogsnext term (“spectators”) that had observed controlled interactions between a human and a previous termdognext term (the “demonstrator”) competing for an object, and that were subsequently allowed to interact freely with both participants. When the competitions were playful, as indicated by signals performed by the human, the spectator was more likely to approach the winner first and/or more rapidly, suggesting that winners of games are perceived as desirable previous termsocialnext term partners. When the human did not perform play signals, changing the previous termsocialnext term context from play to contest over a resource, spectators were slower to approach either of the participants, suggesting that participants in contests were less desirable as previous termsocialnext term partners than participants in games. If the previous termdognext term was prevented from seeing the game, it still reacted differently to the winner and the loser, but its behaviour was not the same as after games that it had seen. We conclude that spectator previous termdogsnext term gain information from the players' subsequent behaviour as well as from direct observation of the game. |
|
| |
Address |
N. J. Rooney, Anthrozoology Institute, School of Clinical Veterinary Sciences, University of Bristol, Langford, Bristol BS40 5DU, U.K. |
|
| |
Corporate Author |
Anthrozoology Institute, University of Bristol, U.K. |
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
Admin @ knut @ |
Serial |
29 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
McGreevy, P.D.; McLean, A.N.; Warren-Smith, A.K.; Waran, N.; Goodwin, D. |
|
| |
Title |
Defining the terms and processes associated with equitation |
Type |
Journal Article |
| |
Year |
2005 |
Publication |
Proceedings of the First International Equitation Science Symposium |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
10-43 |
|
| |
Keywords |
|
|
| |
Abstract |
|
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
Cited By (since 1996): 6; Export Date: 24 October 2008 |
Approved |
no |
|
| |
Call Number |
Admin @ knut @ |
Serial |
4616 |
|
| Permanent link to this record |
