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Author Beauchamp, G.; Kacelnik, A.
Title Effects of the knowledge of partners on learning rates in zebra finches Taeniopygia guttata Type (up) Journal Article
Year 1991 Publication Animal Behaviour. Abbreviated Journal Anim. Behav.
Volume 41 Issue 2 Pages 247-253
Keywords
Abstract Many interpretations of the adaptive value of group living involve tranfer of knowledge. However, according to learning theory, being in a pair with a knowledgeable partner can have paradoxical consequences. Obtaining food by following a skilled companion may reduce the ability of naive individuals to learn about clues that signal the occurrence of food. This study examined the relation between learning and following in paris of zebra finches. Knowledgeable partners were trained to obtain food from a computer-controlled dispenser by using the information provided by a signal. For non-knowledgeable partners, the signal was irrelevant and could not be used to predict foraging opportunities. The rate of learning about the signal by naive birds that shared the experience of either knowledgeable or nonknowledgeable tutors was then examined. Naive birds learned more slowly as a result of being in a pair with a knowledgeable than a non-knowledgeable partner. Well-informed mates acted as a reliable cue to predict foraging opportunities, and thus overshadowed the independent signal. The knowledge of a partner influences learning rates in naive individuals, but in the opposite direction to that predicted by earlier accounts of learning in social contexts.
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Notes Approved no
Call Number Serial 2115
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Author Dugatkin, L.; Alfieri, M.
Title Tit-For-Tat in guppies (Poecilia reticulata): the relative nature of cooperation and defection during predator inspection Type (up) Journal Article
Year 1991 Publication Evolutionary Ecology Abbreviated Journal Evol. Ecol.
Volume 5 Issue 3 Pages 300-309
Keywords Game theory – Tit-For-Tat – predator inspection – guppy
Abstract Summary The introduction of game-theoretical thinking into evolutionary biology has laid the groundwork for a heuristic view of animal behaviour in which individuals employ “strategies” – rules that instruct them how to behave in a given circumstance to maximize relative fitness. Axelrod and Hamilton (1981) found that a strategy called Tit-For-Tat (TFT) is one robust cooperative solution to the iterated Prisoner's Dilemma game. There exists, however, little empirical evidence that animals employ TFT. Predator inspection in fish provides one ecological context in which to examine the use of the TFT strategy.
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Notes Approved no
Call Number Equine Behaviour @ team @ Serial 2177
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Author Dugatkin, L.A.
Title Dynamics of the TIT FOR TAT strategy during predator inspection in the guppy (Poecilia reticulata) Type (up) Journal Article
Year 1991 Publication Behavioral Ecology and Sociobiology Abbreviated Journal Behav. Ecol. Sociobiol.
Volume 29 Issue 2 Pages 127-132
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Abstract One well-known solution to the iterated Prisoner's Dilemma is the TIT FOR TAT strategy. This strategy has three “characteristics” associated with it. TIT FOR TAT is nice (cooperates on the first move of a game), retaliatory (plays defect against an individual that defected on the prior move), and forgiving (cooperates with an individual which has defected in the past but cooperates in the present). Predator inspection behavior in guppies (Poecilia reticulata) was examined in order to determine whether guppies displayed these three characteristics. Results indicate that while it can be quite difficult to translate the abstract concepts of niceness, retaliation, and forgiveness into measurable behaviors, the data support the hypothesis that guppies display the three characteristics associated with the TIT FOR TAT strategy.
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Call Number Equine Behaviour @ team @ Serial 2178
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Author Ben-Shahar, R
Title Selectivity in large generalist herbivores: feeding patterns of African ungulates in a semi-arid habitat Type (up) Journal Article
Year 1991 Publication African Journal of Ecology Abbreviated Journal Afr. J. Ecol.
Volume 29 Issue 4 Pages 302-315
Keywords diet; forage production; grazing; wildebeest; zebra
Abstract Feeding habits of free-ranging wildebeest and zebra were monitored in a semi-arid nature reserve, bordering the southwestern part of Kruger National Park, South Africa. The purpose of study was to distinguish and define the feeding niches of two roughage grazers that occur in similar habitat types. The monthly compositions of diets were evaluated by direct observations of feeding bouts over a period of two years when rainfall patterns were average and animal populations were stable. Other analyses evaluated the standing biomass of grass species in the reserve during the wet summer and dry winter seasons.

A considerable overlap of grass species composition was found in the diets of wildebeest and zebra. Ordination of bi-monthly records of the diet composition showed greater variations in scores of grasses in zebra diet in comparison to wildebeest. Seasonal patterns were more apparent in the wildebeest diet. Preference ranking of grass species indicated that zebra diet remained constant in winter and summer. Wildebeest diet however, alternated with seasons, showing high preferences during the winter months for grass species which were rejected during summer.

The combined assessment of results from three separate statistical methods analysing temporal patterns and preferences in diet composition revealed contradictory trends. The solution, however, relied on the initial assumptions posed. Hence, wildebeest and zebra are essentially generalist feeders which show a limited amount of preference in their choice of diet.
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Call Number Equine Behaviour @ team @ Serial 2226
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Author Lucas, Z.; Raeside, J.I.; Betteridge, K.J.
Title Non-invasive assessment of the incidences of pregnancy and pregnancy loss in the feral horses of Sable Island Type (up) Journal Article
Year 1991 Publication Journal of Reproduction and Fertility. Supplement Abbreviated Journal J Reprod Fertil Suppl
Volume 44 Issue Pages 479-488
Keywords Abortion, Veterinary/*epidemiology; Animals; Animals, Wild/*physiology; Atlantic Islands; Estrogens/analysis; Feces/chemistry; Female; Fertilization; Gestational Age; Horse Diseases/*epidemiology; Horses; Incidence; Pregnancy; *Pregnancy, Animal
Abstract Field observations of 400 totally unmanaged feral horses on Sable Island, Nova Scotia, were complemented by oestrogen determinations in faecal samples from 154 identified females over a 4-year period (454 mare-years). Of mares that were sampled throughout the year and subsequently produced foals, 92.1% exhibited elevated faecal oestrogens between 15 October and 30 March. The results confirm that faecal oestrogens are a useful indicator of pregnancy after approximately 120 days gestation. Distribution of foaling resembled that seen in other feral populations, with 95% of births occurring from April through July. The foaling rate for mares aged 3 years or older was 62.0%, with 50.7% of mares foaling in 3 or 4 years. Foaling rates were low (4.1%) in mares bred as yearlings and rose with age to 70.8% in those bred as 4-year-olds. Fetal loss after Day 120 was deduced from faecal oestrogens to be 26.0% overall, with marked variation from year to year (9.6-37.3%) and with age (70.0% in those bred as yearlings, decreasing to 5.6% in those bred as 4-year-olds). Of 58 mares aged 2 years or older that were sampled every year, about half (49.6%) the barren years were attributable to fetal loss after 120 days gestation. All mares conceived in at least 2 of the 4 years, suggesting that pregnancy loss, even after Day 120, is as important as failure to conceive in causing barren years.
Address Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Canada
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ISSN 0449-3087 ISBN Medium
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Notes PMID:1795292 Approved no
Call Number Equine Behaviour @ team @ Serial 2247
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Author Garott, R.A.
Title Sex Ratios and Differential Survival of Feral Hors Type (up) Journal Article
Year 1991 Publication Journal of Animal Ecology Abbreviated Journal J Anim Ecol
Volume 60 Issue 3 Pages 929-936
Keywords
Abstract (1) Sex and age data were collected on 60 111 feral horses (Equus caballus L.) removed from eighty-nine areas in Nevada, Wyoming, and Oregon between 1976 and 1987. (2) Sex ratios of young seldom differed from parity; however, sex ratios of adults were commonly skewed toward females. No evidence of differential capture probability between adult males and females could be detected; therefore, skewed adult sex ratios were attributed to differential survival. (3) Age-specific trends in sex ratios indicated that the proportion of males steadily decreased from near parity in foals, to lows of 0.61-0.77 in the 4-5-year age-classes. The trend then reversed with males becoming predominant (1.08-1.36) in the > 10 years age-class. (4) Population simulations suggest that survival diffentials of 0.05-0.07, favouring females to 4 years of age, and 0.02-0.04 favouring males in older age-classes were required to mimic observed age-specific sex ratio changes. To obtain the high proportion of males in the > 10-years age-class, onset of senescence also had to be earlier for females. (5) Causes for differential survival in the immature age-classes are uncertain, but may relate to behavioural or metabolic differences between the sexes. Differential survival between adult males and females is attributed to differences in the energetic costs of reproduction and disparity in their reproductive life spans.
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Call Number Equine Behaviour @ team @ Serial 2294
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Author Kirkpatrick, J.F.; Turner, J.W.
Title Changes in herd stallions among feral horse bands and the absence of forced copulation and induced abortion Type (up) Journal Article
Year 1991 Publication Behavioral Ecology and Sociobiology Abbreviated Journal Behav. Ecol. Sociobiol.
Volume 29 Issue 3 Pages 217-219
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Abstract Forced copulation and induced abortion were investigated in a herd of feral horses inhabiting a coastal barrier island. Eight mares were diagnosed pregnant in August and October 1989 by means of urinary and fecal steroid metabolites, prior to documented changes in herd stallions. These mares were observed for harassment and forced copulation by the new stallions and for the presence of foals during the spring and summer of 1990. No incidents of harassment or attempts at forced copulation were witnessed and seven of the eight mares produced foals in 1990. These data indicate that forced copulation and induced abortion are not common events among all feral horse herds and suggest reinvestigation of this hypothesized phenomenon.
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Notes Approved no
Call Number Equine Behaviour @ team @ Serial 2327
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Author Marean, C.W.; Gifford-Gonzalez, D.
Title Late Quaternary extinct ungulates of East Africa and palaeoenvironmental implications Type (up) Journal Article
Year 1991 Publication Nature Abbreviated Journal Nature
Volume 350 Issue 6317 Pages 418-420
Keywords
Abstract UNGULATE communities of two East African savannas, the Serengeti and Athi-Kapiti Plains, are dominated by wildebeest (Connochaetes taurinus) supplemented by zebra (Equus burchelli), topi (Damaliscus lunatus), hartebeest (Alcelaphus buselaphus), buffalo (Syncerus caffer) eland (Taurotragus oryx) and gazelles (Gazella grand and G. thomsoni)1-3. Before this research, little was known of East African large mammal communities in the Late Pleistocene and early to middle Holocene. We document an extinct impala-sized alcelaphine antelope that is numerically dominant in Late Pleistocene archaeofaunal assemblages from the Athi-Kapiti Plains. The extinct giant buffalo Pelorovis antiquus is present, and a number of arid-adapted regionally extinct species are common. The small alcelaphine is rare in northern Tanzania, but regionally extinct arid-adapted species are present in Late Pleistocene deposits. These data indicate that as recently as 12,000 years ago, the large mammal community structure of East African savannas was very different and dry grasslands and arid-adapted ungulates expanded at least as far south as northern Tanzania during the Last Glacial Maximum.
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Notes 10.1038/350418a0 Approved no
Call Number Equine Behaviour @ team @ Serial 2345
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Author Duncan, I.J.; Petherick, J.C.
Title The implications of cognitive processes for animal welfare Type (up) Journal Article
Year 1991 Publication Journal of Animal Science Abbreviated Journal J. Anim Sci.
Volume 69 Issue 12 Pages 5017-5022
Keywords *Animal Welfare; Animals; Animals, Domestic/*psychology; *Cognition
Abstract In general, codes that have been designed to safeguard the welfare of animals emphasize the importance of providing an environment that will ensure good health and a normal physiological and physical state, that is, they emphasize the animals' physical needs. If mental needs are mentioned, they are always relegated to secondary importance. The argument is put forward here that animal welfare is dependent solely on the cognitive needs of the animals concerned. In general, if these cognitive needs are met, they will protect the animals' physical needs. It is contended that in the few cases in which they do not safeguard the physical needs, it does not matter from a welfare point of view. The human example is given of being ill. It is argued that welfare is only adversely affected when a person feels ill, knows that he or she is ill, or even thinks that he or she is ill, all of which processes are cognitive ones. The implications for welfare of animals possessing certain cognitive abilities are discussed. For example, the extent to which animals are aware of their internal state while performing behavior known to be indicative of so-called states of suffering, such as fear, frustration, and pain, will determine how much they are actually suffering. With careful experimentation it may be possible to determine how negative they feel these states to be. Similarly, the extent to which animals think about items or events absent from their immediate environment will determine how frustrated they are in the absence of the real item or event but in the presence of the cognitive representation.
Address University of Guelph, Canada
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ISSN 0021-8812 ISBN Medium
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Notes PMID:1808195 Approved no
Call Number Equine Behaviour @ team @ Serial 2753
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Author Curtis, S.E.; Stricklin, W.R.
Title The importance of animal cognition in agricultural animal production systems: an overview Type (up) Journal Article
Year 1991 Publication Journal of Animal Science Abbreviated Journal J. Anim Sci.
Volume 69 Issue 12 Pages 5001-5007
Keywords *Agriculture; Animal Population Groups/*psychology; *Animal Welfare; Animals; *Behavior, Animal; *Cognition; Heat; Helplessness, Learned; Housing, Animal/standards; Immobilization; Nesting Behavior; Pain/psychology/veterinary
Abstract To describe and then fulfill agricultural animals' needs, we must learn more about their fundamental psychological and behavioral processes. How does this animal feel? Is that animal suffering? Will we ever be able to know these things? Scientists specializing in animal cognition say that there are numerous problems but that they can be overcome. Recognition by scientists of the notion of animal awareness has been increasing in recent years, because of the work of Griffin and others. Feeling, thinking, remembering, and imagining are cognitive processes that are factors in the economic and humane production of agricultural animals. It has been observed that the animal welfare debate depends on two controversial questions: Do animals have subjective feelings? If they do, can we find indicators that reveal them? Here, indirect behavioral analysis approaches must be taken. Moreover, the linear additivity of several stressor effects on a variety of animal traits suggests that some single phenomenon is acting as a “clearinghouse” for many or all of the stresses acting on an animal at any given time, and this phenomenon might be psychological stress. Specific situations animals may encounter in agricultural production settings are discussed with respect to the animals' subjective feelings.
Address University of Illinois, Urbana 61801
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Series Editor Series Title Abbreviated Series Title
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ISSN 0021-8812 ISBN Medium
Area Expedition Conference
Notes PMID:1808193 Approved no
Call Number Equine Behaviour @ team @ Serial 2754
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