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Author (up) Bell, A.M.
Title Evolutionary biology: animal personalities Type
Year 2007 Publication Nature Abbreviated Journal Nature
Volume 447 Issue 7144 Pages 539-540
Keywords Aggression/physiology/psychology; Animals; Behavior, Animal/*physiology; *Evolution; Humans; *Models, Biological; Personality/genetics/*physiology; Reproduction/genetics/physiology; Risk-Taking; Selection (Genetics)
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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 1476-4687 ISBN Medium
Area Expedition Conference
Notes PMID:17538607 Approved no
Call Number Equine Behaviour @ team @ Serial 4099
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Author (up) Boyce, P.N.; McLoughlin, P.D.
Title Ecological Interactions Involving Feral Horses and Predators: Review with Implications for Biodiversity Conservation Type Journal Article
Year 2021 Publication The Journal of Wildlife Management Abbreviated Journal Jour. Wild. Mgmt.
Volume n/a Issue n/a Pages
Keywords apparent competition; artificial selection; community ecology; conservation; feral horse (Equus ferus caballus); life history; predator-prey dynamics
Abstract ABSTRACT For many ecosystems, feral horses are increasingly becoming an important if not dominant component of ungulate biomass and hence influence on community dynamics. Yet we still know little of how horses contribute to key ecological interactions including predator-prey and indirect competitive relationships at a community level. Notably, feral species like horses can exhibit life-history traits that differ from that of native (mainly artiodactyl) herbivore competitors. Artificial selection for traits like increased, early, or extended reproduction that have yet to be reversed by natural selection, coupled with naturally selected differences in anatomy and behavior, in addition to unique management objectives for horses compared to other species, means that the dynamics of feral horse populations are not likely to align with what might be expected of other large herbivores. Unexpected population dynamics and inherent biological asymmetries between native ungulates and feral horses may therefore influence the former via direct competition for shared resources and through enemy-mediated interactions like apparent competition. In several localities feral horses now co-exist with multiple native prey species, some of which are in decline or are species at risk. Compounding risks to native species from direct or indirect competitive exclusion by horses is the unique nature and socio-political context of feral horse management, which tends towards allowing horse populations to be limited largely by natural, density-dependent factors. We summarize the inherent asymmetries between feral horse biology and that of other ungulate prey species with consequences for conservation, focusing on predator-prey and emerging indirect interactions in multi-prey systems, and highlight future directions to address key knowledge gaps in our understanding of how feral horses may now be contributing to the (re)structuring of food webs. Observations of patterns of rapid growth and decline, and associated skews in sex ratios of feral horse populations, indicate a heightened potential for indirect interactions among large ungulate prey species, where there is a prevalence of feral horses as preferred prey, particularly where native prey are declining. In places like western North America, we expect predator-prey interactions involving feral horses to become an increasingly important factor in the conservation of wildlife. This applies not only to economically or culturally important game species but also at-risk species, both predators (e.g., wolves [Canis lupus], grizzly bears [Ursus arctos]) and prey (e.g., woodland caribou [Rangifer tarandus caribou]), necessitating an ecological understanding of the role of horses in natural environments that goes beyond that of population control. ? 2021 The Wildlife Society.
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Publisher John Wiley & Sons, Ltd Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-541x ISBN Medium
Area Expedition Conference
Notes https://doi.org/10.1002/jwmg.21995 Approved no
Call Number Equine Behaviour @ team @ Serial 6642
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Author (up) De Cremer, D.; van Dijk, E.
Title Leader--Follower Effects in Resource Dilemmas: The Roles of Leadership Selection and Social Responsibility Type Journal Article
Year 2008 Publication Group Processes Intergroup Relations Abbreviated Journal
Volume 11 Issue 3 Pages 355-369
Keywords followers, leadership selection, resource allocations, resource dilemmas, social responsibility
Abstract Previous research on the allocation of scarce resources shows that when people are assigned labels of leader or follower in their group, leaders allocate more of the scarce resources to themselves than followers do. In three laboratory studies, we examine the idea that how people are selected for the leader role (i.e. election or appointment) determines whether leaders take more or equal shares (relative to followers) from a common resource. In a first experiment, we show that participants were more accepting of norm violating behavior by an appointed versus elected leader. In a second experiment, we show that when participants were assigned to a leader or follower role, allocations of appointed leaders differed significantly from those of elected leaders and followers, whereas there was no difference between the two latter conditions. Moreover, elected leaders were shown to feel more social responsibility than both appointed leaders and followers. In a final experiment, we show that when participants were primed with the concept of social responsibility (relative to a neutral condition) no difference in allocations between appointed and elected leaders emerged.
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 4805
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Author (up) Drent, P.J.; van Oers, K.; van Noordwijk, A.J.
Title Realized heritability of personalities in the great tit (Parus major) Type Journal Article
Year 2003 Publication Proceedings. Biological sciences / The Royal Society Abbreviated Journal Proc Biol Sci
Volume 270 Issue 1510 Pages 45-51
Keywords Aggression; Animals; Animals, Domestic; Animals, Wild; *Behavior, Animal; Breeding; Exploratory Behavior; Female; *Heredity; Male; Selection (Genetics); Songbirds/*genetics/*physiology; Variation (Genetics)
Abstract Behaviour under conditions of mild stress shows consistent patterns in all vertebrates: exploratory behaviour, boldness, aggressiveness covary in the same way. The existence of highly consistent individual variation in these behavioural strategies, also referred to as personalities or coping styles, allows us to measure the behaviour under standardized conditions on birds bred in captivity, link the standardized measurements to the behaviour under natural conditions and measure natural selection in the field. We have bred the great tit (Parus major), a classical model species for the study of behaviour under natural conditions, in captivity. Here, we report a realized heritability of 54 +/- 5% for early exploratory behaviour, based on four generations of bi-directional artificial selection. In addition to this, we measured hand-reared juveniles and their wild-caught parents in the laboratory. The heritability found in the mid-offspring-mid-parent regression was significantly different from zero. We have thus established the presence of considerable amounts of genetic variation for personality types in a wild bird.
Address Netherlands Institute of Ecology, PO Box 40, 6666 ZG Heteren, The Netherlands. drent@cto.nioo.knaw.nl
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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:12590770 Approved no
Call Number refbase @ user @ Serial 591
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Author (up) Dubois, C.; Manfredi, E.; Ricard, A.
Title Optimization of breeding schemes for sport horses Type Journal Article
Year 2008 Publication Livestock Science Abbreviated Journal
Volume 118 Issue 1-2 Pages 99-112
Keywords Breeding scheme; Horse; Jumping; Optimization; Genetic trend, Multistage selection
Abstract A selection scheme for jumping sport horses is modelled with four stages of selection for males and one stage for females. The selection objective included three traits: conformation and gaits (CG, weighted 20%), competition jumping (CJ, weighted 60%) and a third trait (TT, weighted 20%) such as sperm quality or orthopaedic status. The first selection stage is based on knowledge of the pedigree with the aim of selecting horses suitable for CG test (at 3 years old) and CJ test (at 5 years old). The second stage includes the horse's own performance with respect to CG and CJ with the aim of selecting horses suitable for the TT test. The third stage is the selection of a limited number of males who are allowed to reproduce. The fourth stage (at 12 years old) takes into account the results of the horse's progeny. Females are selected in one step, whatever the number of performances measured at 5 years old. The annual genetic response was 9.4% genetic standard deviation of the objective, 2.6% for CG, 9.0% for CJ and 1.5% for TT. Results showed that selection by progeny testing did not contribute much to genetic response (12% of progeny issued from proven sires), the female pathway represented 26% of genetic response, TT was difficult to improve when the genetic correlation was unfavourable (- 0.6% genetic standard deviation for - 0.20 genetic correlation), and should consequently be directed towards the use of molecular markers. When compared with a selection scheme involving a station test, genetic response was the same if the breeding values used for selection before entering the station test took into account the results of the relatives for CJ and CG. This revealed the importance of an extensive performance test (like for competition performance) when designing breeding schemes for sport horses.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1871-1413 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 4759
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Author (up) Dubois, C.; Ricard, A.
Title Efficiency of past selection of the French Sport Horse: Selle Francais breed and suggestions for the future Type Journal Article
Year 2007 Publication Livestock Science Abbreviated Journal
Volume 112 Issue 1-2 Pages 161-171
Keywords Horse; Genetic trend; Selection; Jumping
Abstract Parameters of genetic trend of Selle Francais (SF) horse breed were studied from 1974 to 2002 and detailed since 1991 because historical BLUP animal model genetic evaluation for jumping competition was available since 1989. During this period, annual births varied from 6000 to 10,000. The annual genetic trend for show jumping was 0.055 of genetic standard deviation between 1985 and 1995 and 0.096 since 1995 without unfavourable trend for dressage (ΔG = + 0.002) and eventing (ΔG = + 0.011). The three parameters of genetic trend: the selection intensity (i = 1.95 for males, 0.48 for females), the accuracy (r = 0.66 for males, 0.60 for females), and the generation interval (L = 12.0 years for males, 11.5 for females) explained this result. Particularities were: a higher number of progeny for best sires which induced true selection intensity equal to 2.21, a new and important selection on progeny (46% births form sires tested on progeny between 2000 and 2002), a high rate of own performance test in competition for mares (45%) which induced high accuracy of mare pathway. However, demographic possibilities were not reached, the possible selection rate for male (1.5%) and females (49%) should increase genetic gain + 14% and + 11% respectively. The generation interval was too long: a better selection at first stage for males, with equal rapid test on progeny and a shorter period of reproduction, i.e. a higher number of foals per sire, should decrease the relative importance of progeny test and should decrease generation interval. The drop of mares aged more than 10 at first progeny should decrease 1.2 year generation interval without loss on accuracy. If breeders keep the same structure (test of stallion and majority of mares on their own performance), they could add new criteria (conformation, gaits...) in the breeding value estimation for SF and maintain the high genetic trend on jumping.
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Notes Approved no
Call Number refbase @ user @ Serial 3946
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Author (up) Dugatkin, L.A.; Mesterton-Gibbons, M.
Title Cooperation among unrelated individuals: reciprocal altruism, by-product mutualism and group selection in fishes Type Journal Article
Year 1996 Publication Biosystems Abbreviated Journal Biosystems
Volume 37 Issue 1-2 Pages 19-30
Keywords By-product mutualism; Cooperative behavior; Fish; Reciprocal altruism; Trait-group selection
Abstract Cooperation among unrelated individuals can evolve not only via reciprocal altruism but also via trait-group selection or by-product mutualism (or some combination of all three categories). Therefore the (iterated) prisoner's dilemma is an insufficient paradigm for studying the evolution of cooperation. We replace this game by the cooperator's dilemma, which is more versatile because it enables all three categories of cooperative behavior to be examined within the framework of a single theory. Controlled studies of cooperation among fish provide examples of each category of cooperation. Specifically, we describe reciprocal altruism among simultaneous hermaphrodites that swap egg parcels, group-selected cooperation among fish that inspect dangerous predators and by-product mutualism in the cooperative foraging of coral-reef fish.
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Notes Approved no
Call Number refbase @ user @ Serial 481
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Author (up) Dunbar, R.I.M.
Title Male and female brain evolution is subject to contrasting selection pressures in primates Type Journal Article
Year 2007 Publication BMC Biology Abbreviated Journal BMC Biol
Volume 5 Issue Pages 21
Keywords Animals; *Brain/physiology; *Evolution; Female; Humans; Male; *Selection (Genetics); *Sex Characteristics
Abstract The claim that differences in brain size across primate species has mainly been driven by the demands of sociality (the “social brain” hypothesis) is now widely accepted. Some of the evidence to support this comes from the fact that species that live in large social groups have larger brains, and in particular larger neocortices. Lindenfors and colleagues (BMC Biology 5:20) add significantly to our appreciation of this process by showing that there are striking differences between the two sexes in the social mechanisms and brain units involved. Female sociality (which is more affiliative) is related most closely to neocortex volume, but male sociality (which is more competitive and combative) is more closely related to subcortical units (notably those associated with emotional responses). Thus different brain units have responded to different selection pressures.
Address British Academy Centenary Research Project, School of Biological Sciences, University of Liverpool, Liverpool, UK. rimd@liv.ac.uk
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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 1741-7007 ISBN Medium
Area Expedition Conference
Notes PMID:17493267 Approved no
Call Number Serial 2100
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Author (up) Edouard, N.; Fleurance, G.; Dumont, B.; Baumont, R.; Duncan, P.
Title Does sward height affect feeding patch choice and voluntary intake in horses? Type Journal Article
Year 2009 Publication Applied Animal Behaviour Science Abbreviated Journal Appl. Anim. Behav. Sci.
Volume 119 Issue 3-4 Pages 219-228
Keywords Patch selection; Intake; Sward height; Horse; Pasture
Abstract The numbers of horses grazing at pasture are increasing in developed countries, so a proper understanding of their feeding selectivity and of the tactics they use for extracting nutrients from swards is essential for the management of horses and grasslands. Resource acquisition in herbivores can be optimised through the modulation of their intake and patch selection, both being strongly dependent on the characteristics of swards. However, the principles by which horses adjust their grazing behaviour in response to variations in sward features are not completely understood. The aim of this study was to determine whether the behaviour of horses conforms to optimal foraging models. We hypothesized that, faced with binary choices between vegetative swards of a good and similar quality at three different heights, horses would select the taller sward, i.e. that allowing a higher reward in terms of dry matter intake rate. Three groups of three 2-year-old saddle horses were grazed on a semi-natural pasture that was managed to produce three contrasting sward heights at 6, 11 and 17 cm, in a Latin-square design. The instantaneous intake rate was determined from bite rate measured at pasture on the three sward heights, and bite mass estimated from measurements using swards offered indoors in experimental trays. Daily dry matter intake was estimated individually by total faecal collection and an estimation of digestibility from faecal nitrogen. Short-term (first 30 min) and daily preferences were assessed from the time spent grazing each sward offered in pair-wise tests at pasture. The results show that daily voluntary intake (an average of 21 g DM kg LW-1 day-1) and total grazing time (an average of 14 h day-1) were independent of sward height and of the choice of patches offered. In choice situations, the animals spent more time grazing on the taller sward, both during the first 30 min and at the daily scale. These results show that horses choose between vegetative patches of a good and similar quality according to the predictions from optimal foraging models, and select the one that they can ingest faster. Further research will now have to explore how the horses will adapt their feeding behaviour when they face a trade-off between sward height and quality.
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Language Summary Language Original Title
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Series Volume Series Issue Edition
ISSN 0168-1591 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 5094
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Author (up) Feh, C.; Munkhtuya, B.
Title Male infanticide and paternity analyses in a socially natural herd of Przewalski`s horses: Sexual selection? Type Journal Article
Year 2008 Publication Behavioural Processes Abbreviated Journal Behav. Process.
Volume 78 Issue 3 Pages 335-339
Keywords DNA paternity analysis; Human disturbance; Male infanticide; Przewalski's horse (Equus ferus przewalskii); Sexual selection
Abstract The sexual selection hypothesis explains infanticide by males in many mammals. In our 11-year study, we investigated this hypothesis in a herd of Przewalski's horses where we had witnessed infanticidal attacks. Infanticide was highly conditional and not simply linked to takeovers. Attacks occurred in only five of 39 cases following a takeover, and DNA paternity revealed that, although infanticidal stallions were not the genetic fathers in four cases out of five, stallions present at birth did not significantly attempt to kill unrelated foals. Infanticide did not reduce birth intervals; only in one case out of five was the infanticidal stallion, the father of the next foal; mothers whose foals were attacked subsequently avoided associating with infanticidal stallions. Therefore, evidence for the sexual selection hypothesis was weak. The “human disturbance” hypothesis received some support, as only zoo bred stallions which grew up in unnatural social groups attacked foals of mares which were pregnant during takeovers.
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Language Summary Language Original Title
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Notes Approved no
Call Number Equine Behaviour @ team @ Serial 4632
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