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Bobbert, M. F., Alvarez, C. B. G., van Weeren, P. R., Roepstorff, L., & Weishaupt, M. A. (2007). Validation of vertical ground reaction forces on individual limbs calculated from kinematics of horse locomotion. J Exp Biol, 210(Pt 11), 1885–1896.
Abstract: The purpose of this study was to determine whether individual limb forces could be calculated accurately from kinematics of trotting and walking horses. We collected kinematic data and measured vertical ground reaction forces on the individual limbs of seven Warmblood dressage horses, trotting at 3.4 m s(-1) and walking at 1.6 m s(-1) on a treadmill. First, using a segmental model, we calculated from kinematics the total ground reaction force vector and its moment arm relative to each of the hoofs. Second, for phases in which the body was supported by only two limbs, we calculated the individual reaction forces on these limbs. Third, we assumed that the distal limbs operated as linear springs, and determined their force-length relationships using calculated individual limb forces at trot. Finally, we calculated individual limb force-time histories from distal limb lengths. A good correspondence was obtained between calculated and measured individual limb forces. At trot, the average peak vertical reaction force on the forelimb was calculated to be 11.5+/-0.9 N kg(-1) and measured to be 11.7+/-0.9 N kg(-1), and for the hindlimb these values were 9.8+/-0.7 N kg(-1) and 10.0+/-0.6 N kg(-1), respectively. At walk, the average peak vertical reaction force on the forelimb was calculated to be 6.9+/-0.5 N kg(-1) and measured to be 7.1+/-0.3 N kg(-1), and for the hindlimb these values were 4.8+/-0.5 N kg(-1) and 4.7+/-0.3 N kg(-1), respectively. It was concluded that the proposed method of calculating individual limb reaction forces is sufficiently accurate to detect changes in loading reported in the literature for mild to moderate lameness at trot.
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McBride, S. D., & Wolf, B. (2007). Using multivariate statistical analysis to measure ovine temperament; stability of factor construction over time and between groups of animals. Appl. Anim. Behav. Sci., 103(1-2), 45–58.
Abstract: The ovine arena test in conjunction with multivariate statistical analysis (factor analysis) may be a means of measuring ovine temperament for practical purposes. Stability of factor construction over time and between groups of animals is considered to demonstrate trait consistency and is, therefore, one of the first steps in validating a temperament/personality test from this perspective. The aim of this study, therefore, was to assess the stability of factor construction, as a measure of trait consistency, using arena test data from three groups of animals with one group (Group 1) tested repeatedly over three rounds (twice at 8 months and once at 22 months of age). Group 1 consisted of 193 mule (Bluefaced Leicester Sire x Scottish Blackface/Welsh Speckled Face dam), ewe lambs (8 months old). Groups 2 and 3 consisted of 189 and 185 mules, respectively (14 months old). All animals were tested for 6 min in a 13 m x 3 m arena. Factor analysis (varimax rotation) was performed twice on the behavioural data (latency to bleat, total number of vocalisations, distance travelled, time spent in different areas of the arena and number of times crossing in and out of pertinent areas), initially using all data recorded on a per minute basis (`Per Minute') for all 6 min of the test (10 factors extracted) and then using total values (`Total'), the summation of the 6 min for each behaviour measured (4 factors extracted). Stability of factor loadings between rounds and between groups was tested using Kendall's coefficient of concordance. For the `Per Minute' data, 5 out of the 10 factors showed significant (p < 0.05) concordance between rounds whilst 9 out of 10 factors showed significant (p < 0.05) concordance between groups. All four factors generated from the `Total' data demonstrated significant (p < 0.05) concordance between rounds and between groups. The four factors generated from the `Total' data were considered to be of potential merit for future studies. These factors were named--`conspecific motivation-fear', `conspecific motivation-distress', `activity' and `low conspecific motivation'.
Keywords: Arena test; Factor analysis; Temperament; Sheep
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Paramastri, Y., Royo, F., Eberova, J., Carlsson, H. - E., Sajuthi, D., Fernstrom, A. - L., et al. (2007). Urinary and fecal immunoglobulin A, cortisol and 11-17 dioxoandrostanes, and serum cortisol in metabolic cage housed female cynomolgus monkeys (Macaca fascicularis). Journal of Medical Primatology, 36(6), 355–364.
Abstract: Background and methods Quantitative enzyme-immunoassays of urinary and fecal immunoglobulin A (IgA), cortisol and 11-17-dioxoandrostanes (11,17-DOA), and serum cortisol in eight metabolic-cage-housed female cynomolgus monkeys were performed. The monkeys were divided into two groups, B and NB. Group B animals were blood sampled every 6 hours, whereas Group NB animals were not handled/blood sampled. Results No differences were recorded between the amounts of feces and urine excreted by the two groups. Group B animals excreted more urinary cortisol than did Group NB animals indicating that restraint-blood sampling resulted in a stress response. Excreted amounts of IgA and 11,17-DOA (urine and feces) did not differ between the groups. Conclusions Urinary cortisol was a reliable marker of the stress associated with repeated blood sampling. Declining amounts of excreted urinary cortisol indicated that cynomolgus monkeys acclimated quickly to repeated blood sampling in metabolism cages. Within and between animal variation in amounts of feces voided demonstrated the importance of expressing fecal markers as ‘amounts excreted per time unit per kg body weight’ rather than just measuring the concentrations in fecal samples.
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Dunbar, R. I. M., & Shultz, S. (2007). Understanding primate brain evolution. Philos Trans R Soc Lond B Biol Sci, 362(1480), 649–658.
Abstract: We present a detailed reanalysis of the comparative brain data for primates, and develop a model using path analysis that seeks to present the coevolution of primate brain (neocortex) and sociality within a broader ecological and life-history framework. We show that body size, basal metabolic rate and life history act as constraints on brain evolution and through this influence the coevolution of neocortex size and group size. However, they do not determine either of these variables, which appear to be locked in a tight coevolutionary system. We show that, within primates, this relationship is specific to the neocortex. Nonetheless, there are important constraints on brain evolution; we use path analysis to show that, in order to evolve a large neocortex, a species must first evolve a large brain to support that neocortex and this in turn requires adjustments in diet (to provide the energy needed) and life history (to allow sufficient time both for brain growth and for 'software' programming). We review a wider literature demonstrating a tight coevolutionary relationship between brain size and sociality in a range of mammalian taxa, but emphasize that the social brain hypothesis is not about the relationship between brain/neocortex size and group size per se; rather, it is about social complexity and we adduce evidence to support this. Finally, we consider the wider issue of how mammalian (and primate) brains evolve in order to localize the social effects.
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Koski, S. E., & Sterck, E. H. M. (2007). Triadic postconflict affiliation in captive chimpanzees: does consolation console? Anim. Behav., 73(1), 133–142.
Abstract: Consolation is a triadic postconflict interaction between a conflict participant and an uninvolved third party. The term consolation implies stress alleviation. Consequently, consolation may be an effective mechanism to alleviate postconflict stress. However, this assumption has not been tested. We tested whether consolation alleviates postconflict stress in captive chimpanzees, Pan troglodytes. In addition, we examined whether consolation is a substitute postconflict interaction for reconciliation. We collected 643 postconflict-matched control pairs on aggressees and 576 on aggressors. Consolation occurred equally frequently with aggressees and aggressors. However, we found no evidence that consolation alleviated stress, regardless of the identity of the consoler. In addition, consolation was also directed to conflict participants with no evident postconflict stress. Furthermore, we found no evidence for consolation being a substitute for reconciliation. The occurrence of consolation did not depend on the occurrence of reconciliation and consolation was not more prevalent with the sex class that reconciled less often or had the highest postconflict stress levels. We conclude that consolation is a postconflict interaction in its own right, the function of which is not likely to be connected to stress alleviation of the consoled individual. We propose that the function of triadic postconflict affiliation, previously labelled as consolation, should be reassessed with regard to the third parties' reasons to affiliate with conflict opponents.
Keywords: chimpanzee; consolation; Pan troglodytes; postconflict affiliation
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Thomsen, L. R., Campbell, R. D., & Rosell, F. (2007). Tool-use in a display behaviour by Eurasian beavers (Castor fiber). Anim. Cogn., .
Abstract: Tool use is rare amongst rodents and has never been recorded in connection with agonistic displays. We witnessed a behaviour, stick display (StD), involving tool use in free-living Eurasian beavers (Castor fiber) that we conclude is a display behaviour. Two beavers were the main performers of the signal that was observed in at least six beavers from three families. Beavers reacted to displays by increased evasive and agonistic behaviours compared with their usual behavioural patterns when at territory borders. The behaviour was almost exclusively seen between rivals at territory borders. We suggest that the display is used in agonistic encounters, mainly in a territorial context.
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Westergaard, G. C., Evans, T. A., & Howell, S. (2007). Token mediated tool exchange between tufted capuchin monkeys (Cebus apella). Anim. Cogn., .
Abstract: Three experiments were conducted to test whether a pair of tufted capuchin monkeys (Cebus apella) could generalize their ability to exchange tokens and tool objects with a human experimenter to similar exchanges with a conspecific partner. Monkeys were tested in side-by-side enclosures, one enclosure containing a tool-use apparatus and one or more token(s), and the other enclosure containing one or more tool object(s). The monkeys willingly transferred tokens and tools to a conspecific with little practice. Following a small amount of training, we also found that the monkeys would select situation-appropriate tokens to exchange for specific tools, but did not select appropriate tool objects in response to another monkey's token transfers. Implications regarding role reversal are discussed.
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Petruso, E. J., Fuchs, T., & Bingman, V. P. (2007). Time-space learning in homing pigeons (Columba livia): orientation to an artificial light source. Anim. Cogn., 10(2), 181–188.
Abstract: Time-space learning reflects an ability to represent in memory event-stimulus properties together with the place and time of the event; a capacity well developed in birds. Homing pigeons were trained in an indoor octagonal arena to locate one food goal in the morning and a different food goal in the late afternoon. The goals differed with respect to their angular/directional relationship to an artificial light source located outside the arena. Further, the angular difference in reward position approximated the displacement of the sun's azimuth that would occur during the same time period. The experimental birds quickly learned the task, demonstrating the apparent ease with which birds can adopt an artificial light source to discriminate among alternative spatial responses at different times of the day. However, a novel midday probe session following successful learning revealed that the light source was interpreted as a stable landmark and not as a surrogate sun that would support compass orientation. Probe sessions following a phase shift of the light-dark cycle revealed that the mechanism employed to make the temporal discrimination was prevailingly based on an endogenous circadian rhythm and not an interval timing mechanism.
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Bermú, & dez, J. é. (2007). Thinking Without Words: An Overview for Animal Ethics. The Journal of Ethics, 11, 319–335.
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Peterson, R. O. (2007). The Wolves of Isle Royale: A Broken Balance. Michigan: The university of Michigan Press.
Abstract: About the Book
“Few can rival what Rolf Peterson has accomplished on Isle Royale. His study, a true classic, offers lessons and examples to us all who hope to do the same. This book reveals some of the secrets and details of this one-of-a-kind wolf study.” -Douglas W. Smith, Leader, Yellowstone Wolf Project For nearly half a century Isle Royale National Park has been the site of a comprehensive study on wolves (2008 marks the fiftieth anniversary)-the world's longest-running study on any wild animal. With its lush northern landscape and wolf and moose populations, the pristine and isolated park presents an ideal laboratory for wildlife biologists. The Wolves of Isle Royale is author and wildlife biologist Rolf Peterson's fascinating firsthand account of the relationship that exists between the wolf and the moose on the island. Illustrated with over 100 photographs, this book reveals the true nature of the mysterious and little-understood wolf, and it offers novel solutions to the conservation crisis as the wolf population falters to its lowest recorded level. Rolf O. Peterson is known worldwide for his wolf research. His photographs have been published in National Geographic, Audubon, and National Wildlife. He is Professor of Wildlife Ecology at Michigan Technological University. Cover photo credit: Rolf O. Peterson |