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Author | Wilson, A.M.; McGuigan, M.P.; Su, A.; van Den Bogert, A.J. | ||||
Title | Horses damp the spring in their step | Type | Journal Article | ||
Year | 2001 | Publication | Nature | Abbreviated Journal | Nature |
Volume | 414 | Issue | 6866 | Pages | 895-899 |
Keywords | Animals; Biomechanics; Elasticity; Forelimb; Gait; Horses/anatomy & histology/*physiology; Leg Bones/*physiology; Locomotion; Models, Biological; Muscle Fibers/physiology; Muscle, Skeletal/anatomy & histology/*physiology; Tendons/anatomy & histology/*physiology; Vibration | ||||
Abstract | The muscular work of galloping in horses is halved by storing and returning elastic strain energy in spring-like muscle-tendon units.These make the legs act like a child's pogo stick that is tuned to stretch and recoil at 2.5 strides per second. This mechanism is optimized by unique musculoskeletal adaptations: the digital flexor muscles have extremely short fibres and significant passive properties, whereas the tendons are very long and span several joints. Length change occurs by a stretching of the spring-like digital flexor tendons rather than through energetically expensive length changes in the muscle. Despite being apparently redundant for such a mechanism, the muscle fibres in the digital flexors are well developed. Here we show that the mechanical arrangement of the elastic leg permits it to vibrate at a higher frequency of 30-40 Hz that could cause fatigue damage to tendon and bone. Furthermore, we show that the digital flexor muscles have minimal ability to contribute to or regulate significantly the 2.5-Hz cycle of movement, but are ideally arranged to damp these high-frequency oscillations in the limb. | ||||
Address | Department of Veterinary Basic Sciences, The Royal Veterinary College, Hatfield, Herts AL9 7TA, UK. awilson@rvc.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 | 0028-0836 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:11780059 | Approved | no | ||
Call Number | Equine Behaviour @ team @ | Serial | 2300 | ||
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Author | Bergstrom, C.T.; Lachmann, M. | ||||
Title | Signaling among relatives. III. Talk is cheap | Type | Journal Article | ||
Year | 1998 | Publication | Proceedings of the National Academy of Sciences of the United States of America | Abbreviated Journal | Proc. Natl. Acad. Sci. U.S.A. |
Volume | 95 | Issue | 9 | Pages | 5100-5105 |
Keywords | Animal Communication; Animals; Costs and Cost Analysis; *Evolution; Interpersonal Relations; Models, Biological | ||||
Abstract | The Sir Philip Sidney game has been used by numerous authors to show how signal cost can facilitate honest signaling among relatives. Here, we demonstrate that, in this game, honest cost-free signals are possible as well, under very general conditions. Moreover, these cost-free signals are better for all participants than the previously explored alternatives. Recent empirical evidence suggests that begging is energetically inexpensive for nestling birds; this finding led some researchers to question the applicability of the costly signaling framework to nestling begging. Our results show that cost-free or inexpensive signals, as observed empirically, fall within the framework of signaling theory. | ||||
Address | Department of Biological Sciences, Stanford University, Stanford, CA 94305, USA. carl@charles.stanford.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 | 0027-8424 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:9560235 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 561 | ||
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Author | Galloux, P.; Barrey, E. | ||||
Title | Components of the total kinetic moment in jumping horses | Type | Journal Article | ||
Year | 1997 | Publication | Equine Veterinary Journal. Supplement | Abbreviated Journal | Equine Vet J Suppl |
Volume | Issue | 23 | Pages | 41-44 | |
Keywords | Algorithms; Animals; Exertion/*physiology; Female; Gravitation; Horses/*physiology; Kinetics; Locomotion/*physiology; Male; Models, Biological; Movement/*physiology; Video Recording | ||||
Abstract | Thirty horses were filmed with a panning camera operating at 50 frames/s as they jumped over a 1.20 x 1.20 m fence. The markers of 9 joints on the horse and 7 joints on the rider were tracked in 2D with the TrackEye system. The centre of gravity and moment of inertia of each segment were calculated using a geometric algorithm and a cylindric model, respectively. The kinetic moment of each part of the horse was calculated after filtering, and resampling of data. This method showed the relative contribution of each body segment to the body overall rotation during the take-off, jump and landing phases. It was found that the trunk, hindlimbs and head-neck had the greatest influence. The coordination between the motion of the body segments allowed the horse to control its angular speed of rotation over the fence. This remained nearly constant during the airborne phase (120 +/- 5 degrees/s). During the airborne phase, the kinetic moment was constant because its value was equal to the moment of the external forces (722 +/- 125 kg x m2/s). | ||||
Address | Ecole Nationale d'Equitation, Terrefort, Saumur, France | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
Series Editor | Series Title | Abbreviated Series Title | |||
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ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | PMID:9354287 | Approved | no | ||
Call Number | Equine Behaviour @ team @ | Serial | 3797 | ||
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Author | Kiltie, R.A.; Fan, J.; Laine, A.F. | ||||
Title | A wavelet-based metric for visual texture discrimination with applications in evolutionary ecology | Type | Journal Article | ||
Year | 1995 | Publication | Mathematical Biosciences | Abbreviated Journal | Math Biosci |
Volume | 126 | Issue | 1 | Pages | 21-39 |
Keywords | Animals; Carnivora; *Ecology; Equidae; *Evolution; Humans; Mathematics; Models, Biological; Moths; *Pattern Recognition, Visual; Pigmentation | ||||
Abstract | Much work on natural and sexual selection is concerned with the conspicuousness of visual patterns (textures) on animal and plant surfaces. Previous attempts by evolutionary biologists to quantify apparency of such textures have involved subjective estimates of conspicuousness or statistical analyses based on transect samples. We present a method based on wavelet analysis that avoids subjectivity and that uses more of the information in image textures than transects do. Like the human visual system for texture discrimination, and probably like that of other vertebrates, this method is based on localized analysis of orientation and frequency components of the patterns composing visual textures. As examples of the metric's utility, we present analyses of crypsis for tigers, zebras, and peppered moth morphs. | ||||
Address | Department of Zoology, University of Florida, Gainesville | ||||
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 | 0025-5564 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:7696817 | Approved | no | ||
Call Number | Equine Behaviour @ team @ | Serial | 2660 | ||
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Author | Kaplan, A.I.; Borodovskii, M.I. | ||||
Title | [Alternative animal behavior: a model and its statistical characteristics] | Type | Journal Article | ||
Year | 1989 | Publication | Nauchnye Doklady Vysshei Shkoly. Biologicheskie Nauki | Abbreviated Journal | Nauchnye Doki Vyss Shkoly Biol Nauki |
Volume | Issue | 3 | Pages | 29-32 | |
Keywords | Animals; *Behavior, Animal; Cognition; Male; Mathematics; *Models, Biological; *Models, Statistical; Rats; Reinforcement (Psychology) | ||||
Abstract | The rats' alternative behaviour in T-maze at simultaneous two-sided food refreshment in 13 trials a day during 6 days has been studied. It has been found that in the first testing days the indexes of alternative behaviour of animals correspond to the characteristics of the random alternation. However, on the 5-6th day of testing in the overwhelming majority of rats the true deviation of alternation index above or below than the theoretical values has been revealed. A question on the existence of two strategies of cognitive behaviour alteration and perseveration in rat population is under discussion. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Russian | Summary Language | Original Title | Al'ternativnoe povedenie zhivotnykh: model' i statisticheskie kharakteristiki | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0470-4606 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:2742929 | Approved | no | ||
Call Number | Equine Behaviour @ team @ | Serial | 2799 | ||
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Author | Tobin, T.; Combie, J.D. | ||||
Title | Performance testing in horses: a review of the role of simple behavioral models in the design of performance experiments | Type | Journal Article | ||
Year | 1982 | Publication | Journal of Veterinary Pharmacology and Therapeutics | Abbreviated Journal | J Vet Pharmacol Ther |
Volume | 5 | Issue | 2 | Pages | 105-118 |
Keywords | Analgesics, Opioid/pharmacology; Animals; Apomorphine/pharmacology; Behavior, Animal/*drug effects; Dose-Response Relationship, Drug; Fentanyl/pharmacology; Horses/*physiology; Methylphenidate/pharmacology; *Models, Biological; Motor Activity/drug effects | ||||
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Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0140-7783 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:6125601 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 1957 | ||
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Author | Gonzalez-Fernandez, J.M.; Atta, S.E. | ||||
Title | Facilitated transport of oxygen in the presence of membranes in the diffusion path | Type | Journal Article | ||
Year | 1982 | Publication | Biophysical Journal | Abbreviated Journal | Biophys J |
Volume | 38 | Issue | 2 | Pages | 133-141 |
Keywords | Animals; Biological Transport, Active; Cell Membrane/*metabolism; Diffusion; Dogs; Horses; Humans; Kinetics; Mathematics; *Models, Biological; Muscles/*metabolism; Oxygen/*metabolism | ||||
Abstract | Most of the experimental observations on facilitated transport have been done with millipore filters, and all the theoretical studies have assumed homogeneous spatial properties. In striated muscle there exist membranes that may impede the diffusion of the carrier myoglobin. In this paper a theoretical study is undertaken to analyze the transport in the presence of membranes in the diffusion path. For the numerical computations physiologically relevant values of the parameters were chosen. The numerical results indicate that the presence of membranes tends to decrease the facilitation. For the nonlinear chemical kinetics of the reaction of oxygen with the carrier, this decrement also depends on the location of the membranes. At the higher oxygen concentration side of each membrane the flow of combined oxygen is transferred to the flow of dissolved oxygen. The reverse process occurs at the lower concentration side. Jump discontinuities of the concentration of the oxygen-carrier compound at each membrane are associated with these transfers. The decrement of facilitation is due to the cumulative effect of these jump discontinuities. | ||||
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Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0006-3495 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:7093418 | Approved | no | ||
Call Number | Equine Behaviour @ team @ | Serial | 3806 | ||
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Author | Seyfarth, R.M. | ||||
Title | A model of social grooming among adult female monkeys | Type | Journal Article | ||
Year | 1977 | Publication | Journal of Theoretical Biology | Abbreviated Journal | J. Theor. Biol. |
Volume | 65 | Issue | 4 | Pages | 671-698 |
Keywords | Animals; Behavior, Animal; Female; *Grooming; Haplorhini/*physiology; *Models, Biological; Reproduction; Social Dominance; Time Factors | ||||
Abstract | Grooming networks among adult female monkeys exhibit two similar features across a number of different species. High-ranking animals receive more grooming than others, and the majority of grooming occurs between females of adjacent rank. A theoretical model which duplicates these features is presented, and the properties of the model are used to explain the possible causation and function of female grooming behaviour. The model illustrates how relatively simple principles governing the behaviour of individuals may be used to explain more complex aspects of the social structure of non-human primate groups. | ||||
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Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0022-5193 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:406485 | Approved | no | ||
Call Number | Equine Behaviour @ team @ | Serial | 5259 | ||
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Author | Hamilton, W.D. | ||||
Title | Geometry for the selfish herd | Type | Journal Article | ||
Year | 1971 | Publication | Journal of theoretical biology | Abbreviated Journal | J. Theor. Biol. |
Volume | 31 | Issue | 2 | Pages | 295-311 |
Keywords | Animals; Anura; *Behavior, Animal; Breeding; Communication; Evolution; Fear; Metallurgy; *Models, Biological; Probability; Snakes; *Spatial Behavior | ||||
Abstract | This paper presents an antithesis to the view that gregarious behaviour is evolved through benefits to the population or species. Following Galton (1871) and Williams (1964) gregarious behaviour is considered as a form of cover-seeking in which each animal tries to reduce its chance of being caught by a predator. It is easy to see how pruning of marginal individuals can maintain centripetal instincts in already gregarious species; some evidence that marginal pruning actually occurs is summarized. Besides this, simply defined models are used to show that even in non-gregarious species selection is likely to favour individuals who stay close to others. Although not universal or unipotent, cover-seeking is a widespread and important element in animal aggregation, as the literature shows. Neglect of the idea has probably followed from a general disbelief that evolution can be dysgenic for a species. Nevertheless, selection theory provides no support for such disbelief in the case of species with outbreeding or unsubdivided populations. The model for two dimensions involves a complex problem in geometrical probability which has relevance also in metallurgy and communication science. Some empirical data on this, gathered from random number plots, is presented as of possible heuristic value. |
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Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
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Series Volume | Series Issue | Edition | |||
ISSN | 0022-5193 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:5104951 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 771 | ||
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Author | McClearn, G.E. | ||||
Title | Behavioral genetics | Type | Journal Article | ||
Year | 1971 | Publication | Behavioral Science | Abbreviated Journal | Behav Sci |
Volume | 16 | Issue | 1 | Pages | 64-81 |
Keywords | Amino Acid Metabolism, Inborn Errors; Animals; Aptitude; Behavior, Animal; Chromosome Aberrations; Cognition; Cytogenetics; Female; *Genetics, Behavioral; Genetics, Population; Humans; Intelligence; Mental Retardation; Mice; Models, Biological; Personality; Phenylketonurias; Pregnancy; Research; Schizophrenia; Sex Chromosome Aberrations; Twins | ||||
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Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
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Series Volume | Series Issue | Edition | |||
ISSN | 0005-7940 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:5105941 | Approved | no | ||
Call Number | Equine Behaviour @ team @ | Serial | 4150 | ||
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