Cooperation in organisms, whether bacteria or primates, has been a difficulty for evolutionary theory since Darwin. On the assumption that interactions between pairs of individuals occur on a probabilistic basis, a model is developed based on the concept of an evolutionarily stable strategy in the context of the Prisoner's Dilemma game. Deductions from the model, and the results of a computer tournament show how cooperation based on reciprocity can get started in an asocial world, can thrive while interacting with a wide range of other strategies, and can resist invasion once fully established. Potential applications include specific aspects of territoriality, mating, and disease.

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The Evolution of Cooperation

Cooperation is needed for evolution to construct new levels of organization. Genomes, cells, multicellular organisms, social insects, and human society are all based on cooperation. Cooperation means that selfish replicators forgo some of their reproductive potential to help one another. But natural selection implies competition and therefore opposes cooperation unless a specific mechanism is at work. Here I discuss five mechanisms for the evolution of cooperation: kin selection, direct reciprocity, indirect reciprocity, network reciprocity, and group selection. For each mechanism, a simple rule is derived that specifies whether natural selection can lead to cooperation.

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Five Rules for the Evolution of Cooperation

http://osenberglab.ecology.uga.edu/wp-content/uploads/2015/09/Charnov-1976-TPB.pdf

Optimal foraging, the marginal value theorem.

Every form of behavior is shaped by trial and error. Such stepwise adaptation can occur through individual learning or through natural selection, the basis of evolution. Since the work of Maynard Smith and others, it has been realized how game theory can model this process. Evolutionary game theory replaces the static solutions of classical game theory by a dynamical approach centered not on the concept of rational players but on the population dynamics of behavioral programs. In this book the authors investigate the nonlinear dynamics of the self-regulation of social and economic behavior, and of the closely related interactions among species in ecological communities. Replicator equations describe how successful strategies spread and thereby create new conditions that can alter the basis of their success, i.e., to enable us to understand the strategic and genetic foundations of the endless chronicle of invasions and extinctions that punctuate evolution. In short, evolutionary game theory describes when to escalate a conflict, how to elicit cooperation, why to expect a balance of the sexes, and how to understand natural selection in mathematical terms.

 Comprehensive treatment of ecological and game theoretic dynamics
 Invasion dynamics and permanence as key concepts
 Explanation in terms of games of things like competition between species

/pdf/evolutionary-games-and-population-dynamics-pax1uk4ywa.pdf

Evolutionary games and population dynamics

Selection on non-random fusion of gametes during the evolution of anisogamy.

We present a series of prospective models of nuptial feeding, mainly for insects. The models examine various optimal male and female strategies, but do not include any element of mate choice in which the female chooses males in relation to the gift he provides.



We find that the female should use the gift to enhance egg size and/or clutch size when gifts represent a relatively large component of the energy resources for the gametes, or when the gift occurs at a relatively late stage in her reproductive cycle. However, if the female receives a single, relatively small gift during her reproductive cycle, she should show a reduced gametic output at the next oviposition. A literature survey revealed several studies that show increases in egg and clutch sizes following gift donation, but we found no instances in which there was a reduction in gametic output. We also find that if gifts are infrequent, there can be significant sexual conflict over the pattern of allocation of donated resources to future offspring. Male interests will generally be best served by a more immediate use of the resources than will be optimal for the female. This may result in selection for male ability to influence vitellogenesis and/or oviposition. Evidence is available which shows that male-derived substances influence female physiology; this might reflect an outcome towards male interests as a result of an arms race in sexual conflict.



Some studies have demonstrated an effect of gift donation on survivorship. We examine models in which gift donation reduces male survival but increases female survival. These suggest that gift donation is most likely to evolve when (1) giving a gift has little effect on male, but a significant effect on female survival, (2) when the male is more likely to father eggs in a later batch, rather than the next batch, and (3) when random mortality is high.

Nuptial Feeding in Insects: Theoretical Models of Male and Female Interests

The reproductive behavior of the dung fly, Scatophaga stercoraria L, has been divided into a series of separate phases; eg searching, genital contact, etc (Parker, 1970b) These are mostly self-explanatory and occur in many animal species An exception, however, is the post-copulatory passive phase oif the male In S stercoraria the average density of males searching around fresh cattle droppings (the site of mating and oviposition) is very high, especially during the population peaks (Parker, 1970a) Females lay several successive batches of eggs and visit the fresh dung only to mate and oviposit (Parker, 1970e) Genital contact begins immediately after a female arriving at the dung is captured by a searching male After copulation the male adopts the passive behavior phase by raising his abdomen away from that of the female but otherwise retaining the same mount posture The female has considerable freedoim of movement and is quite free to oviposit; the only contact maintained by the male is the grasp of his front tarsi around the junction between her thoirax and abdomen The male's middle and hind legs rest on the dung surface Ovipositing pairs are attacked repeatedly by searching males and "take-overs" (where the attacker displaces the original male and takes possession of the female) are not infrequent (Parker, 1970d) The female initiates separation after oviposition, and her behavior also determines whether or not a passive phase is adopted by the male (Parker, 1970e) Females remain quiescent only when both fresh dung is present and they still have mature eggs to lay Otherwise they show "swaying" reactions during copula and immediately after which cause the males to separate without a passive phase These reactions resemble the rejection reactions shown by many unreceptive female Diptera The term "passive phase" may be defined as a stage of the male's reproductive behavior during which he remains mounted on or otherwise attached to the female but without true genital contact between the two sexes "Copula" or "copulation" is regarded as synonymous with true genital contact Sometimes the terms "amplexus" (literally, an embrace) and "tandem behavior" have been used loosely for situations resembling passive phases "Passive phase" is used because it cointra-sts, with the phase of active sperm transfer; it is not intended to imply general inactivity of the male Passive phase males often show vigoirous rejection reactions when attacked by single males, Passive phases occur infrequently in widely separated groups, of animals, though their adaptive significance has attracted little speculation and apparently no quantitative analysis The aim of the present paper is to investigate the possible selective values of the passive phase in S stercoraria, and to consider its origin and the method by which it may have evolved

https://www.onlinelibrary.wiley.com/doi/pdf/10.1111/j.1558-5646.1970.tb01812.x

The reproductive behavior and the nature of sexual selection in scatophaga stercoraria l. (diptera: scatophagidae). vii. the origin and evolution of the passive phase.

The pattern of parental investment (PI) seen in nature is a product of the simultaneous resolution of conflicts of interest between the members of a family. How these conflicts are resolved depends upon the mating system, the genetic mechanism, on whether extra PI affects current or future offspring, and the behavioural mechanisms underlying supply and demand of PI. Until recently very little empirical work has been done to underpin these key determinants of conflict resolution. This review examines recent empirical progress in understanding both (1) how conflict is resolved and (2) its evolutionary consequences. How offspring demand interacts with parental supply of resources determines how conflict is resolved. Two extremes are: passive parental choice of competing offspring, relating to offspring control of resource allocation, and active parental choice relating to parental control. Although most previous empirical work has tended to conclude or assume that parents primarily control resource allocation decisions, recent studies explicitly examining predictions from theoretical analyses have shown that offspring control of resource allocation is more important than previously realised. The amount of PI supplied at resolution depends not on who controls food allocation, however, but on the nature of the supply and demand mechanisms. These have yet to be established experimentally, but a recent regression model illustrates how this could be achieved in the field. Determination of the effect of supply on demand (ESD) and the effect of demand on supply (EDS) mechanisms is critical to parent–offspring conflict theory, which has not been adequately tested empirically. There is an underlying, and until recently untested, assumption of models of intrafamilial conflict that there is genetic variation for both offspring demand and parental supply behaviours, so that the behaviours can coevolve. Recent studies on great tits, burrower bugs and mice all found evidence for genetic variation in supply and demand behaviours, but the predicted negative correlation between genes expressed in mothers and their offspring (i.e. parent–offspring coevolution), was found only for burrower bugs. The lack of a negative relationship for great tits and mice may have been a consequence of antagonistic coevolution between the sexes (sexual conflict). These studies illustrate the importance of the underlying genetics and mating system in determining conflict resolution, and point to the need for new models (especially of interbrood competition) taking differences in the genetics and the co-evolution of the ESD and EDS mechanisms into account. We also discuss the importance of the comparative approach in determining evolutionary consequences of conflicts, and use the recent work on growth costs of begging to illustrate the difficulties of measuring costs of conflict in an evolutionary currency. The recent growth in empirical work on conflicts in families illustrates an increasing, and increasingly productive, integration between theoreticians and empiricists.

/pdf/parental-investment-and-family-dynamics-interactions-between-glqef0kcst.pdf

Geoff A. Parker

Papers

Selection on non-random fusion of gametes during the evolution of anisogamy.

Nuptial Feeding in Insects: Theoretical Models of Male and Female Interests

The reproductive behavior and the nature of sexual selection in scatophaga stercoraria l. (diptera: scatophagidae). vii. the origin and evolution of the passive phase.

Parental investment and family dynamics: interactions between theory and empirical tests

Sperm competition games: sperm selection by females