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| Author | Noë, R.; Hammerstein, P. | ||||
| Title | Biological markets: supply and demand determine the effect of partner choice in cooperation, mutualism and mating | Type | Journal Article | ||
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1994 | Publication | Behavioral Ecology and Sociobiology | Abbreviated Journal | Behav. Ecol. Sociobiol. |
| Volume | 35 | Issue | 1 | Pages | 1-11 |
| Keywords | Biomedical and Life Sciences | ||||
| Abstract | The formation of collaborating pairs by individuals belonging to two different classes occurs in the contexts of reproduction and intea-specific cooperation as well as of inter-specific mutualism. There is potential for partner choice and for competition for access to preferred partners in all three contexts. These selective forces have long been recognised as important in sexual selection, but their impact is not yet appreciated in cooperative and mutualistic systems. The formation of partnerships between members of different classes has much in common with the conclusion of trade agreements in human markets with two classes of traders, like producers and consumers, or employers and employees. Similar game-theoretical models can be used to predict the behaviour of rational traders in human markets and the evolutionarily stable strategies used in biological markets. We present a formal model in which the influence of the market mechanism on selection is made explicit. We restrict ourselves to biological markets in which: (1) Individuals do not compete over access to partners in an agonistic manner, but rather by outcompeting each other in those aspects that are preferred by the choosing party. (2) The commodity the partner has to offer cannot be obtained by the use of force, but requires the consent of the partner. These two restrictions ensure a dominant role for partner choice in the formation of partnerships. In a biological market model the decision to cooperate is based on the comparison between the offers of several potential partners, rather than on the behaviour of a single potential partner, as is implicitly assumed in currently accepted models of cooperation. In our example the members of one class A offer a commodity of fixed value in exchange for a commodity of variable value supplied by the other class, B. We show that when the B-class outnumbers the A-class sufficiently and the cost for the A-class to sample the offers of the B-class are low, the choosiness of the A-class will lead to selection for the supply of high value commodities by the B-class (Fig. 3a). Under the same market conditions, but with a high sampling cost this may still be the evolutionariy stable outcome, but another pair of strategies proves to be stable too: relaxed choosiness of class A coupled with low value commodities supplied by class B (Fig. 3b). We give a number of examples of mating, cooperative and mutualistic markets that resemble the low sampling cost situation depicted in Fig. 3a. | ||||
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| Publisher | Springer Berlin / Heidelberg | Place of Publication | Editor | ||
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| ISSN | 0340-5443 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 5404 | ||
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| Author | Mesterton-Gibbons, M.; Dugatkin, L.A. | ||||
| Title | Toward a theory of dominance hierarchies: effects of assessment, group size, and variation in fighting ability | Type | Journal Article | ||
| Year |
1995 | Publication | Behavioral Ecology | Abbreviated Journal | Behav. Ecol. |
| Volume | 6 | Issue | 4 | Pages | 416-423 |
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| Abstract | We introduce assessment to the analysis of dominance hierarchies by exploring the effect of an evolutionarily stable fighting rule when there is variation in resource holding potential (RHP) and RHP is not a perfectly reliable predictor of the outcome of a fight. With assessment, the probability of a linear hierarchy decreases with group size but can remain appreciable for groups of up to seven or eight individuals, whereas it decreases virtually to zero if there is no assessment. The probability of a hierarchy that correlates perfectly with RHP is low unless group size is small. | ||||
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| Notes | 10.1093/beheco/6.4.416 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 447 | ||
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| Author | Ben-Shahar, R. | ||||
| Title | Habitat classification in relation to movements and densities of ungulates in a semi-arid savanna | Type | Journal Article | ||
| Year |
1995 | Publication | African Journal of Ecology | Abbreviated Journal | Afr. J. Ecol. |
| Volume | 33 | Issue | Pages | 50-63 | |
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| Abstract | Habitat types were classified in a semi-arid nature reserve in South Africa in order to assess the spatial requirements of resident ungulates, namely zebra, wildebeest and impala. Multivariate analyses showed patterns of soil factors and plant species associations that corresponded with variations of local geological formations and the abundance of plants. The response of ungulates to habitats of different degrees of complexity in terms of soils and plant species associations was examined on the basis of annual occurrence. New habitat types were described through merging or subdividing the existing classification. New habitat categories which corresponded with high occurrences of ungulates provided better indications of the resource requirements for large herbivores. Wildebeest were restricted in their habitat requirements and were characterized by high seasonal densities in bottom lands, particularly during the late wet period. There was a considerable overlap in the preference of habitat types between wildebeest and zebra although zebra were aggregated during longer periods within the dolerite formation. Impala had a consistent annual preference for the granite formation where seepage lines and bottom lands were inhabited seasonally by large herd concentrations. Résumé On a classifié les types d'habitat dans une réserve naturelle semiaride d'Afrique du Sud, dans le but d'évaluer les exigences spatiales des ongulés qui y vivent, c'est à dire les zèbres, les gnous et les impalas. Des analyses multivariées ont révélé des schémas pour les facteurs du sol et pour les associations d'espèces végétales qui correspondent aux variations des formations géologiques locales et à l'abon-dance des plantes. On a examiné la réponse des ongulés à des habitats de complexité différente en termes de sols et d'associations d'espéces végétales, d'après leur présence annuelle. On a décrit de nouveaux types d'habitats en fusionnant ou en subdivisant la classification existante. Les nouvelles catégories d'habitats qui correspondaient à des présences abondantes d'ongulés ont fourni de meilleures indications sur les ressources exigées par les grands herbivores. Les gnous se limitaient aux endroits qui répondaient a leurs exigences et se caractérisaient par de hautes densités saisonnières dans les régions basses, spécialement pendant la dernière saison des pluies. Il y avait un recouvrement considérable des types d'habitats préferés par les gnous et les zébres, encore que les zébres se rassemblent plus longtemps dans la formation doléritique. Les impalas marquent une préférence annuelle constante pour la formation granitique où les sources et les terres basses sont occupées de façon saisonnière par des hardes très concentrées. |
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| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 2227 | ||
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| Author | Noë, R.; Hammerstein, P. | ||||
| Title | Biological markets | Type | Journal Article | ||
| Year |
1995 | Publication | Trends in Ecology & Evolution | Abbreviated Journal | Trends. Ecol. Evol |
| Volume | 10 | Issue | 8 | Pages | 336-339 |
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| Abstract | In biological markets, two classes of traders exchange commodities to their mutual benefit. Characteristics of markets are: competition within trader classes by contest or outbidding; preference for partners offering the highest value; and conflicts over the exchange value of commodities. Biological markets are currently studied under at least three different headings: sexual selection, intraspecific cooperation and interspecific mutualism. The time is ripe for the development of game theoretic models that describe the common core of biological markets and integrate existing knowledge from the separate fields. | ||||
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| ISSN | 0169-5347 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 4993 | ||
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| Author | Connor, R.C. | ||||
| Title | Altruism among non-relatives: alternatives to the 'Prisoner's Dilemma' | Type | Journal Article | ||
| Year |
1995 | Publication | Trends in Ecology & Evolution | Abbreviated Journal | Trends Ecol Evol |
| Volume | 10 | Issue | 2 | Pages | 84-86 |
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| Abstract | Triver's model of reciprocal altruism, and its descendants based on the Prisoner's Dilemma model, have dominated thinking about cooperation and altruism between non-relatives. However, there are three alternative models of altruism directed to non-relatives. These models, which are not based on the Prisoner's Dilemma, may explain a variety of phenomena, from allogrooming among impala to helping by non-relatives in cooperatively breeding birds and mammals. | ||||
| Address | Division of Biological Sciences and The Michigan Society of Fellows, Museum of Zoology, University of Michigan, Ann Arbor MI, 48109, USA | ||||
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| Language | English | Summary Language | Original Title | ||
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| ISSN | 0169-5347 | ISBN | Medium | ||
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| Notes | PMID:21236964 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 5407 | ||
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| Author | Barton, R.A.; Byrne, R.W.; Whiten, A. | ||||
| Title | Ecology, feeding competition and social structure in baboons | Type | Journal Article | ||
| Year |
1996 | Publication | Behavioral Ecology and Sociobiology | Abbreviated Journal | Behav. Ecol. Sociobiol. |
| Volume | 38 | Issue | 5 | Pages | 321-329 |
| Keywords | Key words Ecology – Competition – Group size – Baboons | ||||
| Abstract | Predictions of the model of van Schaik (1989) of female-bonding in primates are tested by systematically comparing the ecology, level of within-group contest competition for food (WGC), and patterns of social behaviour found in two contrasting baboon populations. Significant differences were found in food distribution (percentage of the diet from clumped sources), feeding supplant rates and grooming patterns. In accord with the model, the tendencies of females to affiliate and form coalitions with one another, and to be philopatric, were strongest where ecological conditions promoted WGC. Group fission in the population with strong WGC was “horizontal” with respect to female dominance rank, and associated with female-female aggression during a period of elevated feeding competition. In contrast, where WGC was low, females' grooming was focused on adult males rather than other females. Recent evidence suggests that group fission here is initiated by males, tends to result in the formation of one-male groups, and is not related to feeding competition but to male-male competition for mates. An ecological model of baboon social structure is presented which incorporates the effects of female-female competition, male-male competition, and predation pressure. The model potentially accounts for wide variability in group size, group structure and social relationships within the genus Papio. Socio-ecological convergence between common baboons and hamadryas baboons, however, may be limited in some respects by phylogenetic inertia. | ||||
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| Notes | Approved | no | |||
| Call Number | refbase @ user @ | Serial | 807 | ||
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| Author | Templeton, J.J.; Giraldeau, L.-A. | ||||
| Title | Vicarious sampling: the use of personal and public information by starlings foraging in a simple patchy environment | Type | Journal Article | ||
| Year |
1996 | Publication | Behavioral Ecology and Sociobiology | Abbreviated Journal | Behav. Ecol. Sociobiol. |
| Volume | 38 | Issue | 2 | Pages | 105-114 |
| Keywords | Social foraging ? Patch sampling ? Public information ? Sturnidae | ||||
| Abstract | Group foragers may be able to assess patch quality more efficiently by paying attention to the sampling activities of conspecifics foraging in the same patch. In a previous field experiment, we showed that starlings foraging on patches of hidden food could use the successful foraging activities of others to help them assess patch quality. In order to determine whether a starling could also use another individual's lack of foraging success to assess and depart from empty patches more quickly, we carried out two experimental studies which compared the behaviour of captive starlings sampling artificial patches both when alone and when in pairs. Solitary starlings were first trained to assess patch quality in our experimental two-patch system, and were then tested on an empty patch both alone and with two types of partner bird. One partner sampled very few holes and thus provided a low amount of public information; the other sampled numerous holes and thus provided a high amount of public information. In experiment 1, we found no evidence of vicarious sampling. Subjects sampled a similar number of empty holes when alone as when with the low and high information partners; thus they continued to rely on their own personal information to make their patch departure decisions. In experiment 2, we modified the experimental patches, increasing the ease with which a bird could watch another's sampling activities, and increasing the difficulty of acquiring accurate personal sampling information. This time, subjects apparently did use public information, sampling fewer empty holes before departure when with the high-information partner than when with the low-information partner, and sampling fewer holes when with the low-information partner than when alone. We suggest that the degree to which personal and public information are used is likely to depend both on a forager's ability to remember where it has already sampled and on the type of environment in which foraging takes place. | ||||
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| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 4198 | ||
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| Author | Meriggi,A.; Lovari, S. | ||||
| Title | A Review of Wolf Predation in Southern Europe: Does the Wolf Prefer Wild Prey to Livestock? | Type | Journal Article | ||
| Year |
1996 | Publication | Journal of Applled Ecology | Abbreviated Journal | J. Appl. Ecol |
| Volume | 33 | Issue | Pages | 1561-1571 | |
| Keywords | Canis lupus, conservation, food habits, prey abundance, prey availability. | ||||
| Abstract | 1. The recent recovery of the wolf in southern Europe has not yet removed the risk of local extinction. Wolf populations are fragmented and often comprise fewer than 500 individuals. In North America, northern and eastern Europe, wolves feed maiiily on wild herbivores. In southern Europe, this canid has apparently adapted to feed also on fruit, rubbish, livestock, small and medium-size mammals. 2. The main conservation problem lies with predation o n domestic ~ingulates,w liich leads to extensive killing of wolves. The reintroduction of wild large herbivores has been advocated as a means of reducing attacks on livestock, but predatiori on the latter may remain high if domestic ungulates are locally abundant. 3. Our synthesis of 15 studies, published in the last 15 years, on food habits of the wolf in southern Europe, has shown that ungulates have been the main diet component overall. A significant inverse correlation was found between the occurrence (%) of wild and domestic ungulates in the diet. The presence of relatively few wild ungulate species was necessary to reduce predation on livestock. 4. Selection of wild and domestic ungulate prey was influenced mainly by their local abundance, but also by their accessibility. Feeding dependence on rubbish was local and rare. In Italy, the consumption of riibbish/fruit and that of ungulates was significantly negatively correlated. Diet breadth increased as the presence of large prey in tlie diet decreased. 5. The simultaneous reintroduction of severa1 wild ungulate species is likely to reduce predation on livestock and may prove to be one of the most effective conservation measures. |
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| Call Number | Equine Behaviour @ team @ | Serial | 6387 | ||
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| Author | Dugatkin, L.A. | ||||
| Title | Winner and loser effects and the structure of dominance hierarchies | Type | Journal Article | ||
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1997 | Publication | Behavioral Ecology | Abbreviated Journal | Behav. Ecol. |
| Volume | 8 | Issue | 6 | Pages | 583-587 |
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| Abstract | In the literature on dominance hierarchies, “winner” and “loser” effects usually are denned as an increased probability of winning at time T, bated on victories at time T-l, T-2, etc, and an increased probability of losing at time T, based on losing at T-1, T-2, etc., respectively. Despite some early theoretical work on winner and loser effects, these factors and how they affect the structure of dominance hierarchies have not been examined in detail. I developed a computer simulation to examine winner and loser effects when such effects are independent of one another (as well as when they interact) and when combatants assess each other's resource-holding power. When winner effects alone were important, a hierarchy in which all individuals held an unambiguous rank was found. When only loser effects were important, a dear alpha individual always emerged, but the rank of others in the group was often unclear because of the scarcity of aggressive interactions. Increasing winner effects for a given value of the loser effect increase the number of individuals with unambiguous positions in a hierarchy and the converse is true for increasing the value of the loser effect for a given winner effect Although winner and loser effects have been documented in a number of species, no study has documented both winner and loser effects (using some controlled, pairwise testing system) and the detailed nature of behavioral interactions when individuals are in groups. I hope the results of this model will spur such studies in the future. | ||||
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| Notes | 10.1093/beheco/8.6.583 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 759 | ||
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| Author | Kahurananga, J.; Silkiluwasha, F. | ||||
| Title | The migration of zebra and wildebeest between Tarangire National Park and Simanjiro Plains, northern Tanzania, in 1972 and recent trends | Type | Journal Article | ||
| Year |
1997 | Publication | African Journal of Ecology | Abbreviated Journal | Afr J Ecol |
| Volume | 35 | Issue | 3 | Pages | 179-185 |
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| Abstract | In 1972, four aerial censuses were carried out to assess the annual migration of zebra and wildebeest between Tarangire National Park and Simanjiro Plains. About 6000 zebra and 10,000 wildebeest were in the Plains in the middle of the rainy season, in April. During the dry season in August the animals were concentrated in the Park. The migration from the Park to the Plains started at beginning of the rains, in November/December. Recent censuses by Tanzania Wildlife Conservation Monitoring (TWCM, 1991, 1995) indicate that an estimated 23,000 zebra and 11,000 wildebeest migrate into the Park from Simanjiro and other wet season areas. Encroaching cultivation is a threat to the migration corridors and sustainability of the ecosystem . Providing benefits from wildlife to communities around the park would safeguard the future of the wildlife. | ||||
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| Call Number | Equine Behaviour @ team @ Kahurananga1997 | Serial | 2312 | ||
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