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1.
We study a dynamic common pool resource game in which current resource stock depends on resource extraction in the previous period. Our model shows that for a sufficiently high regrowth rate, there is no commons dilemma: the resource will be preserved indefinitely in equilibrium. Lower growth rates lead to depletion. Laboratory tests of the model indicate that favorable ecological characteristics are necessary but insufficient to encourage effective CPR governance. Before the game, we elicit individual willingness to follow a costly rule. Only the presence of enough rule-followers preserves the resource given favorable ecological conditions. 相似文献
2.
T. R. Pope 《Behavioral ecology and sociobiology》2000,48(4):253-267
Evaluation of evolutionary mechanisms proposed to promote cooperative behavior depends on the relative influence of the behavior
on the reproductive success of individuals, the reproductive success of the group in which they interact behaviorally, and
the degree of gene correlation among cooperators. The genetic relationship within cooperative coalitions of female red howler
monkeys was examined for three populations with different densities and growth rates. Patterns of gene correlation change
within coalitions is documented using data from the mitochondrial and nuclear genomes, and long-term census monitoring. Differences
in fecundity and infant survivorship within and between groups of unrelated (rˉ=0) and related (rˉ≥ 0.25) females are compared. Females that emigrate from their natal groups form coalitions with other migrant females. These
coalitions attempt to establish a territory and, once successful in producing offspring, exclude other females from feeding
resources. Females in these coalitions had different mtDNA haplotypes and a genetically estimated mean r of 0, supporting demographic data on emigration patterns indicating that these females rarely have the opportunity to form
coalitions with kin. Patterns of recruitment and rate of matriline development within social groups supported behavioral data
indicating that females actively attempt to promote their own matriline as breeders over that of other females, and that some
matrilines are more successful at this than others. Mean r among females was significantly higher in coalitions established as social groups for several generations (rˉ=0.44). In these groups, females all shared the same mtDNA haplotype, and mtDNA haplotype divergence was significantly higher
between than within groups. Females in coalitions with kin had significantly higher reproductive success than females in unrelated
coalitions in all populations. This difference was not a function of coalition size, number of males, socionomic sex ratio,
or primiparity, although anecdotal evidence suggests that allomothering may compensate for inept new mothers in related coalitions
more often than in unrelated ones. Differences in territory quality could not be ruled out as a potential causal factor in
the saturated populations, but were unlikely in the low-density, growing population. There were substantial differences among
long-established coalitions in overall reproductive output in all three populations, and this was significantly correlated
with the number of breeding females. Increase in coalition size was a function of both group age and the behavioral tolerance
among females. Regardless of the underlying reasons for the patterns observed, reproductive success clearly increases with
degree of gene correlation among females within cooperative coalitions, and coalitions that recruit more daughters produce
more offspring. The nature of the cooperative relationship among group females directly influences both of these outcomes.
This is associated with substantial genetic differentiation among social groups within populations, creating conditions in
which genetic tendencies towards cooperative behavior can become tightly associated with group reproductive success.
Received: 15 September 1999 / Revised: 27 April 2000 / Accepted: 27 May 2000 相似文献
3.
Aggression and resource sharing among foundresses in the social wasp Polistes dominulus: testing transactional theories of conflict 总被引:3,自引:0,他引:3
Tug-of-war models of within-group conflict predict that the frequency of conflict will be positively related to the degree
of reproductive sharing within the group; in contrast, a negative relationship supports transactional models, in which reproductive
payments among group members limit the degree of within-group selfishness. We tested predictions of the tug-of-war and transactional
models by examining cofoundress interactions during the founding (preworker) phase of colony development in 30 naturally nesting
colonies of the paper wasp Polistes dominulus. We found that the mean rate of foundress aggression and the mean probability of food sharing were significantly negatively
associated, which supports the prediction of the transactional, not the tug-of-war model. Further, cofoundress aggression
significantly increased over the founding phase (independently of temperature), while the fraction of aggression initiated
by the dominant (alpha) foundress significantly decreased over this period. We show that both of these results are predicted
by the transactional model of within-group conflict. Interestingly, the alpha’s rate of aggression was significantly positively
temperature dependent, while the beta’s was not. This indicates that the alpha’s aggression level may often be near her physiological
maximum, while the beta’s aggression is limi- ted by other factors, contradicting the prediction of the tug-of-war model.
Moreover, the alpha’s aggression was significantly positively temperature dependent only in the second half of the founding
period, as predicted by the transactional model since this is when there is least reproductive sharing. Finally, our results
indicate that the alpha’s level of aggression depends on the resources controlled by the beta.
Received: 18 January 2000 / Revised: 19 June 2000 / Accepted: 24 June 2000 相似文献
4.
5.
分析了日益繁忙的台湾海峡这一黄金水道潜在的大规模突发性溢油风险,指出了建立台湾海峡溢油应急计划的迫切性,并提出该计划的框架思路,呼呈两携手合作共同抗御海峡溢油。 相似文献
6.
Biological markets: supply and demand determine the effect of partner choice in cooperation,mutualism and mating 总被引:12,自引:0,他引:12
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. 相似文献
7.
The common occurrence of food transfers within human hunter–gatherer and forager–horticulturalist groups presents exciting test cases for evolutionary models of altruism. While kin biases in sharing are consistent with nepotism based on kin selection, there is much debate over the extent to which reciprocal altruism and tolerated scrounging provide useful explanations of observed behavior. This paper presents a model of optimal sharing breadth and depth, based on a general non-tit-for-tat form of risk-reduction based reciprocal altruism, and tests a series of predictions using data from Hiwi and Ache foragers. I show that large, high variance food items are shared more widely than small, easily acquired food items. Giving is conditional upon receiving in pairwise interactions and this correlation is usually stronger when the exchange of value rather than quantities is considered. Larger families and low producing families receive more and give less, consistent with the notion that marginal value may be a more salient currency than quantity.
相似文献
Michael GurvenEmail: Phone: +1-805-8932202 |
8.
Social network theory has made major contributions to our understanding of human social organisation but has found relatively
little application in the field of animal behaviour. In this review, we identify several broad research areas where the networks
approach could greatly enhance our understanding of social patterns and processes in animals. The network theory provides
a quantitative framework that can be used to characterise social structure both at the level of the individual and the population.
These novel quantitative variables may provide a new tool in addressing key questions in behavioural ecology particularly
in relation to the evolution of social organisation and the impact of social structure on evolutionary processes. For example,
network measures could be used to compare social networks of different species or populations making full use of the comparative
approach. However, the networks approach can in principle go beyond identifying structural patterns and also can help with
the understanding of processes within animal populations such as disease transmission and information transfer. Finally, understanding
the pattern of interactions in the network (i.e. who is connected to whom) can also shed some light on the evolution of behavioural
strategies. 相似文献
9.
A common explanation for hunting in groups is that doing so yields a greater per capita caloric benefit than hunting solitarily.
This is logical for social carnivores, which rely exclusively on meat for energy, but arguably not for omnivores, which obtain
calories from either plant or animal matter. The common chimpanzee, Pan troglodytes, is one of the few true omnivores that regularly hunts in groups. Studies to date have yielded conflicting data regarding
the payoffs of group hunting in chimpanzees. Here, we interpret chimpanzee hunting patterns using a new approach. In contrast
to the classical assumption that hunting with others maximizes per capita caloric intake, we propose that group hunting is
favored because it maximizes an individual’s likelihood of obtaining important micronutrients that may be found in small quantities
of meat. We describe a mathematical model demonstrating that group hunting may evolve when individuals can obtain micronutrients
more frequently by hunting in groups than by hunting solitarily, provided that group size is below a certain threshold. Twenty
five years of data from Gombe National Park, Tanzania are consistent with this prediction. We propose that our ‘meat-scrap’
hypothesis is a unifying approach that may explain group hunting by chimpanzees and other social omnivores. 相似文献
10.
在全球围绕"低碳"减排博弈的背景下,从合作竞争的角度,分析国际低碳减排过程中的多个缔约国家之间的合作竞争行为及其动态平衡过程。重点用博弈论的相关原理对国际低碳减排市场背后的多个利益群体做一个全局性的分析,对全球低碳减排过程中的一些利益争夺现象进行解释,试图揭露出全球低碳减排博弈背后各个利益群体的谋划与动机;最后提醒中国在下一轮的低碳减排博弈过程中要有所准备。 相似文献