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Author Berger, J.; Cunningham, C.
Title Size-Related Effects on Search Times in North American Grassland Female Ungulates Type Journal Article
Year (up) 1988 Publication Ecology Abbreviated Journal
Volume 69 Issue 1 Pages 177-183
Keywords no keywords available
Abstract Feeding and searching (&#61; vigilance) rates arise as a result of many interrelated factors including trophic level, diet, reproductive condition, sex, habitat, body mass, and potential predation pressure. Because of unique ecological conditions in which the confounding influences of all but two of these variables could be minimized, we examined the hypothesis that body mass alone accounts for interspecific differences in search times, and tested it with females of four sympatric native North American ungulates (Bison bison, Antilocapra americana, Ovis canadensis, and Odocoileus hemionus). When the effects of group size were controlled, smaller bodied species were more vigilant (per unit body mass) than larger ones. However, search times (ST) also scaled to body mass, and between 81 and 97&#37; of the ST variance was explained by either exponential or power functions. To remove the potential bias that predators exert different influences on species of varying size, search times of bison in areas with and without their major predator, wolves (Canis lupus), were contrasted; search times did not differ between sites. Our results highlight the importance of designing field research that controls for confounding variables prior to attempting to scale behavioral processes to ecological events. See full-text article at JSTOR
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Publisher Ecological Society of America Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
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ISSN 0012-9658 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 2233
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Author Berger, J,
Title Social systems, resources, and phylogenetic inertia: an experimental test and its limitations Type Book Chapter
Year (up) 1988 Publication Ecology of Social Behavior Abbreviated Journal
Volume Issue Pages 157-186
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Publisher Academic Press Place of Publication San Diego Editor Slobochikoff, C.N.
Language Summary Language Original Title Ecology of Social Behavior
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Notes Approved no
Call Number Equine Behaviour @ team @ Serial 2234
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Author de Waal, F. B.
Title Dominance “style” and primate social organization. Type Book Chapter
Year (up) 1989 Publication Comparative Socioecology Abbreviated Journal
Volume Issue Pages 243-263
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Publisher Blackwell Science Place of Publication Editor Standen, V.; Foley, R. A.
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN 978-0632023615 Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 2864
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Author Ginsberg, J. R; Rubenstein, D. I.
Title Sperm competiton and variation in zebra mating behaviour Type Journal Article
Year (up) 1990 Publication Behavioral Ecology and Sociobiology Abbreviated Journal Behav. Ecol. Sociobiol.
Volume 26 Issue 6 Pages 427-434
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Abstract Data are presented on the breeding behavior of two zebra species to test whether intra- and interspecific variation in male reproductive behavior and physiology are correlated with differences in female promiscuity. In one species, plains zebra (Equus burchelli) females live in closed membership single male groups and mate monandrously. In the other species, the Grevy's zebra (E. grevyi) females live in groups whose membership is much more temporary. Typically, associations with individual males are brief and mating is polyandrous. However, some females – those having just given birth – reside with one male for long periods, mating monandrously. These differences in female mating behavior generate variability in the potential for sperm competition. We show that behavioral differences in male investment in reproductive activities correlate with the potential for sperm competition. When mating with promiscuous mares, Grevy's zebra stallions made a greater investment in reproductive behavior (calling, mounting, ejaculations) than did stallions of either species when mating with monandrous females. The evolution of large testes size in the Grevy's zebra, when compared to the congeneric plains zebra, horse, and mountain zebra, allows for this increased investment.
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Notes from Professor Hans Klingels Equine Reference List Approved yes
Call Number Serial 1113
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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 Journal Article
Year (up) 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 Journal Article
Year (up) 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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Notes Approved no
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 Journal Article
Year (up) 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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Notes Approved no
Call Number Equine Behaviour @ team @ Serial 2226
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Author Garott, R.A.
Title Sex Ratios and Differential Survival of Feral Hors Type Journal Article
Year (up) 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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Notes Approved no
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 Journal Article
Year (up) 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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Call Number Equine Behaviour @ team @ Serial 2327
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Author Dugatkin, L.A.; Alfieri, M.
Title Guppies and the TIT FOR TAT strategy: preference based on past interaction Type Journal Article
Year (up) 1991 Publication Behavioral Ecology and Sociobiology Abbreviated Journal Behav. Ecol. Sociobiol.
Volume 28 Issue 4 Pages 243-246
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Abstract The evolution of cooperation requires either (a) nonrandom interactions, such that cooperators preferentially interact with other cooperators, or (b) conditional behaviors, such that individuals act cooperatively primarily towards other cooperators. Although these conditions can be met without assuming sophisticated animal cognition, they are more likely to be met if animals can remember individuals with whom they have interacted, associate past interactions with these individuals, and base future behavior on this information. Here we show that guppies (Poecilia reticulata), in the context of predator inspection behavior, can identify and remember (for at least 4 h) the “more cooperative” among two conspecifics and subsequently choose to be near these individuals in future encounters.
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Notes Approved no
Call Number Equine Behaviour @ team @ Serial 3397
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