BACKGROUND: Today’s societal changes, including high rate of change and increasing information flows, are increasing the demand on the individual mental capacity. It becomes increasingly difficult to analytically process all the different dilemmas and everyday decisions as individuals have a limited mental capacity available to make these decisions. Thus, it has been suggested that ego-depleted relies more heavily on intuition, which is less burdensome, when making decision. However little is known about to what extent intuitive decisions differ from analytic. Are ego-depleted individuals more or less likely to maximize outcome in moral dilemmas involving conflicting values? Do ego depleted individuals become more or less willing to cooperate? Do ego depleted individuals become more or less altruistic? Is our intuition more or less in accordance with Homo Economicus?AIM: Starting from a Dual Process perspective on decision-making the aim of this study is to examine how ego depletion affects moral judgment and pro-social decisions.METHOD: A laboratory experiment involving 115 subjects, using real monetary incentives, was conducted among students at Linköping University. Subjects were randomized into one of two treatments. Everything was identical across treatments except for the initial ego-depletion manipulation. Using a standard paradigm for ego-depletion subjects in treatment 1 were put under high cognitive load while subjects in treatment two were put under low cognitive load. Subjects faced 16 questions divided into four different decision tasks: Moral dilemmas, Public Goods game, two types of Dictator Game where the type of sacrifice subjects could make in order to contribute money to charity was varied.RESULTS: Subjects in the high cognitive load treatment made fewer consequentialists moral judgments compared to other subjects (p = 0.075). The effect is especially strong when looking only at high-conflict dilemmas such as Crying Baby. No difference between treatments was found for the public goods games. In the dictator game involving monetary sacrifice subjects donated less money to charity when put under high cognitive load. However the finding was not significant (p = 0.292). No difference was found in the dictator game involving effort as personal sacrifice since almost everyone chooses to donate to charity.CONCLUSION: According to The Dual Process perspective this essay shows that intuitive thinking does not evidently lead to that they makes decision that more or less is in accordance with Homo Economicus. The connection between ego depletion and pro-social decisions is more complex. Further research needs to investigate which different mental shortcuts that individuals uses in various types of pro-social decisions and why intuitive and analytical decision-making differ between different decisions. Further research within the area can identify potential mechanisms and policies that can support individuals’ capacity to make decisions in accordance with their own and society’s preferences.

Cooperation in joint enterprises poses a social dilemma. How can altruistic behavior be sustained if selfish alternatives provide a higher payoff? This social dilemma can be overcome by the threat of sanctions. But a sanctioning system is itself a public good and poses a second-order social dilemma. In this paper, we show by means of deterministic and stochastic evolutionary game theory that imitation-driven evolution can lead to the emergence of cooperation based on punishment, provided the participation in the joint enterprise is not compulsory. This surprising result - cooperation can be enforced if participation is voluntary - holds even in the case of 'strong altruism', when the benefits of a player's contribution are reaped by the other participants only. (authors' abstract)

Les services de tourisme de nature fournis par le patrimoine naturel sont des produits composites et le plus souvent non marchands. Financer la préservation de ce patrimoine par ses usagers est donc tributaire d’une connaissance fine des préférences des touristes et de la valeur qu’ils accordent à la nature. Cette thèse vise de contribuer au débat sur le financement de la préservation des espaces naturels et leurs aménités par les touristes en considérant comme point d’entrée l’hétérogénéité des comportements individuels selon une double perspective. D’abord, nous examinons les déterminants de cette hétérogénéité en termes de la demande de séjours de tourisme en pleine nature, ensuite nous nous penchons sur l’analyse de l’hétérogénéité en termes du mécanisme de contribution choisi par les agents, à savoir, un mécanisme de contribution volontaire ou un mécanisme de contribution contre une service rendu. Les motivations non-économiques de contribution et plus globalement les facteurs cognitifs, en lien avec d’autres caractéristiques individuelles des touristes structurent notre réflexion tout au long de cette thèse. Enfin, les résultats obtenus via cette analyse sont mis en contraste avec ceux issus de la mis en exergue d’un instrument de participation des touristes déjà mis en oeuvre: la taxation. Nous proposons une application aux séjours d’été effectués dans la région de l’estuaire de la Gironde en France. / Tourism services provided by natural environment are composites goods and often non-market. Funding the preservation of this heritage by its own users depends on a profound knowledge of the preferences of tourists and the value they place on nature. This thesis aims to contribute to the debate on the funding of natural areas and amenities preservation programs by tourists. To do so we consider as an entry point the individual’s behavior heterogeneity from two perspectives. First, we examine the determinants of heterogeneity in terms of the demand of nature tourism stay, and then we focus on the analysis of heterogeneity in terms of the contribution mechanism chosen by the agents, e.g., voluntary contribution mechanism or contribution mechanism against a service. The non-economic motivations for contributing and overall cognitive factors, considered in conjunction with other tourists’ individual characteristics, is the main thread structuring our reflection throughout this thesis. Finally, the results obtained through this analysis are contrasted with those from an instrument of tourists contributions already implemented: taxation. We propose an application for summer stays in the region of the Gironde estuary in France.

Au cours des 150 dernières années, l'évolution de la coopération n'a cessé d'intriguer les biologistes de l'évolution. Les comportements coopératifs, qui procurent un avantage direct au bénéficiaire, ne peuvent être sélectionnés que si, pour le coopérateur, les bénéfices directs et/ou indirects dépassent le coût. De nombreuses observations chez l'Homme et chez d'autres espèces animales suggèrent que les comportements coopératifs pourraient être maintenus par la sélection sexuelle. Pourtant, ce champ de recherche est quasiment inexploré, que ce soit chez l'Homme ou chez les autres espèces sociales. Afin d'examiner le rôle potentiel de la sélection sexuelle sur les comportements coopératifs, deux modèles biologiques ont été utilisés : l'Homme et la Souris glaneuse (Mus spicilegus). Chez l'Homme, la propension à coopérer a été quantifiée dans deux populations humaines (française et sénégalaise) principalement par des méthodes empruntées à l'économie expérimentale (jeu du bien public). Chez la souris glaneuse, l'investissement individuel dans la construction collective d'un tumulus pour l'hivernage a été mesuré en captivité. Les résultats soutiennent partiellement nos prédictions, à savoir : (i) que les individus coopèrent davantage en présence de partenaires sexuels potentiels, (ii) que les coopérateurs sont préférés comme partenaires sexuels, et que (iii) ces préférences conduisent à un appariement selon la coopérativité. De plus, ils suggèrent que des traits physiques (visuels, olfactifs, ou acoustiques) puissent être utilisés pour détecter la coopérativité d'un individu. Chez l'Homme, en particulier, des traits statiques du visage, dont au moins certains sont lisibles inter-culturellement, semblent impliqués. Enfin, une éventuelle association entre les comportements coopératifs et une hormone sexuelle, la testostérone, a été examinée. Pris dans leur ensemble, nos résultats suggèrent que la sélection sexuelle pourrait être impliquée dans l'évolution et le maintien de la coopération et ouvrent donc la voie à de nouvelles recherches, examinant son influence dans diverses populations humaines, ainsi que dans de nombreuses autres espèces sociales. Mots clés : Coopération, Altruisme, Générosité, Investissement parental, Attractivité, Jeu du bien public, Choix de partenaire, Homogamie, signal de coopérativité et détection, Régulation hormonale, Testostérone. / Over the past 150 years, the evolution of cooperation has challenged evolutionary biologists. Cooperative behaviour provide a benefit to the recipient and can only be selected for if it also provides direct and/or indirect benefits to the actor that accepted the costs of the cooperative action. Many observations in humans and other animal species suggest that cooperative behaviour could be maintained by sexual selection. However, the hypothesis that sexual selection could be involved in the evolution of cooperation has not received much attention in the recent literature. In order to examine the potential role of sexual selection in cooperative behaviour, two biological models were used: humans and the Mound-building mouse (Mus spicilegus). In two human populations (French and Senegalese populations), cooperativeness was quantitatively measured, mainly by an economic game (the public good game). The spontaneous cooperativeness exhibited during collective mound-building for overwintering was assessed in captivity for Mus spicilegus. The results partly support our predictions: (i) individuals cooperativeness increase in the presence of potential sexual partners, (ii) cooperators are preferred as sexual partners, (iii) these preferences lead to assortative mating based on cooperativeness. Moreover, they suggest that physical traits (visual, olfactory, or acoustic) could be used to detect individual cooperativeness. In humans, static facial traits seem to be involved, and some of them appear to be inter-culturally readable. Finally, a potential association between cooperative behaviour and testosterone levels, a sex hormone, was examined. Together, these results suggest that sexual selection could be involved in the evolution and the maintenance of cooperation. Furthers studies are needed, in different human populations and in different social species, to further investigate the role of sexual selection in cooperative behaviour. Keywords: Cooperation, Altruism, Generosity, Parental investment, Attractiveness, Public Good Game, Mate choice, Homogamy, Detection, Signaling, Hormonal regulation, Testosterone.

[pt] Suicídio por contágio: a maneira pela qual a imprensa fala da morte voluntária. Partindo da experiência profissional do jornalista, o trabalho relaciona as formulações teóricas de Durkheim com o tipo de tratamento dado pela imprensa contemporânea às pessoas que tiram a própria vida. Fez-se uma leitura das reportagens sobre suicídio publicadas pelo jornal O Globo à luz dos conceitos de egoísmo, altruísmo e anomia. Buscou-se, ainda, estabelecer como a linguagem utilizada se relaciona com comportamentos sociais anteriores e externos à criação dos próprios textos. / [en] Suicide by contagion: the way in which the press talks about voluntary death. Coming from the professional experience as journalist, the work relates Durkheim´s theory with the kind of treatment given by the contemporary press to the people who kill themselves. The features about the subject published in O Globo newspaper in 2004 has been re-read, bearing in mind the concepts of egoism, altruism and anomy. It has been tried to establish as well how the language used relates itself with the social behaviours that are previous and external to the creation of the own texts.

Thesis (MPH.) -- University of Limpopo, 2012 / The objectives of the study: To determine the knowledge, attitudes and practices of black employees of The University of Limpopo (Turfloop campus) about blood donation. To determine the degree of willingness by blacks to donate as well as suggesting some solutions to improve the performance by the South African National Blood Services. Design: A descriptive study utilizing a self-reported questionnaire was carried out. Setting: The University of Limpopo Turfloop Campus in the Limpopo Province of South Africa. Material and Methods: A total of 138 employees participated in the study. With the aid of Predictive Analytics Software (PASW), 136 male and 101 female participants were randomly selected from the 40 University departments. The mean ages by gender was 36.91, ±10, 06 years for males, and 41.93, ±9, 35 years for females. The mean ages by donor status was 40.24, ±10, 15 years for donors and 37.94, ±9, 9 years for non-donors. Outcome measures: Subjects demographic variables were determined by the use of a pre-tested self-reported questionnaire, which covered personal characteristics such as gender, age, residence, number of household members, marital status, educational background, faculty or department of vi employment, as well as the monthly income bracket. Knowledge, attitudes and practices regarding blood donation were also assessed using the pre-tested self-developed questionnaire. The following information was included: previous practices, current and lifetime practices of blood donation. Results: There was a general lack of practice of blood donation despite the presence of average knowledge relating to matters of blood donation amongst the black employees of the University of Limpopo, (Turfloop campus). There was no difference between black females and males as far as blood donation was concerned. There was a reflection of similar practices of blood donation by both genders. Blood donation generally started at a very late age due to early lack of exposure, information and awareness. Conclusion: Findings from this study showed that the prevalence of non-donors amongst the blacks is high. The attitudes and practices of non-donors towards donation were generally less favourable, but it can be argued that a high percentage of these findings may likely change with the right interventions.

Dans cette thèse, notre objectif est d'optimiser les stratégies de transmission et de réception dans un réseau où il y a peu ou pas de gestion centrale des ressources du tout, et o'u les nœuds ont une connaissance limitée du canal avec seulement un lien restreint entre eux. En particulier, les ́émetteurs ont la plupart du temps des informations locales seulement sur le canal, et nous considérons qu'il n'y a pas de partage des données 'a transmettre aux utilisateurs, ce qui empêche la transmission conjointe en système virtuel MIMO. L'utilisation commune des ressources du système (par exemple en transmettant en même temps et dans la même bande de fréquence) conduit 'a la génération d'interférence au niveau des différents récepteurs, ce qui rend la gestion des interférences essentielle. En considérant l'optimisation du précodeur dans le cadre de la théorie des jeux, des stratégies extrêmes, égoïste ou altruiste, peuvent être ́définies. Un émetteur égoïste agit en prenant compte de son propre intérêt et recherche la maximisation de son propre rapport signal sur bruit plus interférence (SINR) sans considération des interférences générées aux autres récepteurs. Un émetteur altruiste, par contre, utilise toutes ses ressources afin d'annuler les interférences qu'il crée aux autres récepteurs. Il est intuitif qu'aucune de ces deux stratégies extrêmes n'est optimale pour maximiser le débit total du réseau. Un travail récent sur le design du vecteur de précodage dans un canal d'interférence MISO (MISO-IC) sans décodage des interférences au récepteur (SUD) a mis en évidence qu'il est possible, en balançant les approches égoïste et altruiste, d'atteindre un point d'opération se situant sur la frontière Pareto optimale de la région de débit, qui est la frontière limitant la région des débits atteignables par l'utilisation de précodage linéaire. En gardant 'a l'esprit ce résultat, nous étudions l'optimisation distribuée des vecteurs de précodage pour le MISO-IC-SUD dans le chapitre 2. Nous développons un algorithme qui est initialisé 'a l'équilibre de Nash (point d'opération égoïste) et se déplace 'a chaque itération vers la solution du zéro-forcing (point d'opération altruiste) 'a pas fixe. L'algorithme s'arrête si un des émetteurs observe une baisse de son débit, imitant ainsi le procédé de négociation. L'algorithme propos ́e atteint un point d'opération proche de la frontière Pareto optimale, et chaque utilisateur obtient un débit supérieur 'a celui qu'il aurait eu 'a l'équilibre de Nash. Nous démontrons ainsi que les joueurs (les paires ́émetteur-récepteur) peuvent atteindre des débits supérieurs dans le MISO-IC-SUD en coopérant et en balançant égoïsme et altruisme. Le problème du design des vecteurs de précodage pour le MISO-IC-SUD est étendu au cas du MIMO-IC-SUD au chapitre 3. En supposant une connaissance locale, nous modélisons ce problème en un jeu bayésien prenant en compte le fait que le canal ne soit pas complètement connu, et o'u les joueurs maximisent l'espérance de leur fonction d'utilité 'a partir des statistiques du canal. Nous trouvons le point d'équilibre de ce jeu bayésien et étudions la maximisation de la somme des débits dans un MIMO-IC-SUD. Nous observons que la maximisation du débit total peut aussi être interprétée dans ce scénario comme un équilibre entre les approches égoïstes et altruistes. Avec cette analyse, un algorithme dans lequel les vecteurs de transmission et de réception sont obtenus par une optimisation alternée aux émetteurs et aux récepteurs est développé. L'algorithme converge vers une solution qui aligne les interférences lorsque le SNR devient large, ce qui implique que le débit total augmente indéfiniment avec le SNR (avec une pente égale aux nombre de degrés de liberté). Dans le régime 'a faible SNR, notre approche fonctionne mieux que les algorithmes conventionnels visant 'a aligner les interférences, ce qui est une conséquence de l'équilibre entre égoïsme et altruisme. En particulier, l'algorithme propos ́e atteint des performances presque optimales dans des réseaux asymétriques pour lesquels certains récepteurs sont soumis 'a du bruit de fond incontrôlé. Dans le chapitre 4, nous considérons enfin des récepteurs ayant la capacité de décoder les interférences (IDC) dans un MISO-IC. Ce degré de liberté additionnel permet aux récepteurs de décoder les interférences et de les soustraire au signal reçu, ce qui permet ainsi d'obtenir une communication sans interférence. En revanche, les choix des récepteurs dépendent des vecteurs de précodage aux émetteurs. Pour chaque choix de vecteur de précodage, nous obtenons un nouveau SISO-IC avec une nouvelle région de capacité correspondante. Ainsi, nous devons choisir pour chaque réalisation d'un canal MISO le vecteur de précodage et la puissance de transmission de manière 'a atteindre un débit maximal après avoir considéré toutes les possibilités pour les actions des récepteurs (décodage des interférences ou traitement des interférences comme du bruit). Il y a trois paramètres influant le design: la structure du récepteur, le vecteur de précodage, et la puissance de transmission. Ces trois paramètres sont interdépendants et l'obtention du triplet optimal est un problème qui a ́et ́e démontré comme étant NP-complet. Quoi qu'il en soit, nous avons simplifié cette analyse en reformulant la région des débits atteignables d'un MISO-IC-IDC comme l'union des régions pour les différentes structures. Ensuite nous avons caractérisé les limites de ces régions de débit atteignable et obtenu ainsi la frontière Pareto optimale du problème initial. Les vecteurs de précodage Pareto optimaux sont obtenus par une combinaison linéaire de deux vecteurs du canal avec des poids dépendant seulement de deux scalaires réels entre zéro et un. Nous utilisons ensuite cette caractérisation de la frontière Pareto optimale pour obtenir une caractérisation du point o'u le débit total maximum est atteint. Cet ensemble de solutions potentielles est un sous-ensemble strict de la frontière Pareto optimale, ce qui réduit ainsi considérablement l'espace de recherche du problème NP-complet initial.

Vilken bör vara den centrala sociala normen? Reciprocitet - ömsesidiga relationer till bådas fördel - jämförs med två andra alternativ: altruism och integritet. Altruism - från självuppoffring i nya testamentet och i mycken ideologi till agentneutralitet i modern filosofi - är den etik som oftast förespråkas. Integritetsetik drivs av mer fåtaliga förespråkare som en övergripande filosofi, men har ett omfattande stöd vad gäller individuella liberala rättigheter. Författaren penetrerar argumenten för och mot dessa tre alternativ. • Backas en etik upp med incitament blir den inte altruistisk - men kan en etik få tillräcklig effekt utan incitament?• Vore det bättre att förespråka en mindre ambitiös, men mer realistisk moral?• Finns det något tankemässigt fel i etisk egoism?• Altruistisk etik kanske inte skall ses som riktlinjer för eget handlande, utan försök att få andra att vara oegennyttiga och själv bli förmånstagare?• Kan en irrationell etik paradoxalt nog prestera rationella resultat?Den empiriska delen av denna avhandling undersöker sambandet mellan etiska åsikter och faktiskt beteende. Med ekonomiska spel som hjälpmedel penetreras korrelationen mellan försökspersonernas etiska uppfattningar och deras agerande i tre olika spel; ultimatumspel, diktatorspel och ultimatumspel med förhandling. Etiska ställningstaganden i skilda frågor visar sig vara korrelerade enligt den modell som kopplar ihop olika specifika åsikter till mönster. Försökspersoner klassas först i de tre etiska grupperna och sedan undersöks om det finns signifikanta skillnader i beteendet mellan grupperna. Det visar sig vara fallet, så ett första konstaterande är att etik inte endast är retorik. Den reciproka gruppen ställer signifikant högre krav för att delta i ett samarbete. När ett spelbeslut är en fråga om generositet finns signifikanta positiva samband med altruistiska värderingar. / <p>Diss. (sammanfattning) Stockholm : Handelshögskolan, 2002</p>

Within social insect colonies, sterile workers are responsible for brood care, while queens are the primary egg-layers. These reproductive caste differences are often accompanied by pronounced morphological distinctions. Queen and worker phenotypic differences are particularly remarkable considering caste is environmentally, rather than genetically, determined. Environmental caste determination can produce intralocus genetic conflict between castes, particularly when homologous traits are highly dimorphic. Therefore, when studying the evolution of social insect caste dimorphism, one must consider the genetic architecture underlying phenotypic expression as well as the selective pressures that have shaped caste morphology. This dissertation presents the results of four studies that investigated factors affecting caste morphology in the social wasp Vespula maculifrons. The first two studies focused on identifying queen morphological traits that were positively associated with queen fitness and would therefore be subject to selection. Queen length, specifically gaster length, was positively associated with overwintering survival and was consistently associated with mating success. Both of these findings suggest that queen gaster length is under selection during two life-history events, mating and overwintering, in which workers do not participate. These findings provide empirical support for the adaptive evolution of a caste dimorphic trait. The third and fourth studies used classical quantitative genetic and morphological analyses to examine the genetic architecture underlying caste dimorphism in V. maculifrons. I determined which traits were under caste-specific selection by analyzing trait allometries and the levels of genetic control, variation, and dimorphism of traits between castes. Little genetic variation for morphological trait size was detected for most worker and queen traits, suggesting a strong influence of environment on phenotypic variation. Additionally, analyses of trait allometries indicated that several queen traits (mass, thorax width and length) were under queen-specific selection. The relationship between thorax length, gaster length, and overall body size is further evidence of selection on length in queens. Overall, these studies provide evidence for the importance of queen-specific selection in the evolution of caste dimorphism. When placed in the broader context of caste evolution, they point to the importance of life-history in shaping the genetic architecture underlying caste dimorphism.

Many animals live in societies of varying degrees of organization. Some individuals in these societies seem to sacrifice their own fitness to increase the fitness of some others. Understanding the forces that mould the evolution of such altruistic behaviour has become a dominant theme in modern evolutionary biology. Primitively eusocial polistine wasps provide excellent model systems to study the evolution of altruism as they show high degrees of plasticity in their behaviour. Different individuals in the same population pursue different social strategies such as nesting alpne or nesting in groups. When wasps nest in groups, usually only one individual becomes the egg layer, while die rest assume the role of sterile workers. Why do the workers not become solitary foundresses and rear their own offspring instead of working to rear the brood of another individual? Here I have used the tropical primitively eusocial wasp Ropalidia marginata to explore some factors that might potentially favour the worker strategy over the solitary founding strategy. Workers in multiple foundress nests may benefit by rearing brood more closely related to them than their own offspring would be. However, from previous work on this species it is known that relatedness between sisters is rather low and that workers therefore rear quite distantly related brood. Therefore, I have concentrated on factors other than genetic relatedness that might potentially favour the worker strategy. A total of 145 naturally initiated nests with different numbers of foundresses was monitored over a period of 16 months, and their productivities were compared. Although the total colony productivity increased, the per capita productivity did not increase with increasing foundress numbers. Colonies with larger foundress numbers did not produce significantly heavier progeny and did not produce them significantly faster than colonies with fewer individuals. The conspecific usurpers preferred to usurp single foundress colonies more often than multiple foundress colonies. Therefore, protection from conspecific usurpers might be an advantage of multiple foundress associations. About 10% of the multiple foundress nests experienced queen turnovers. This provides a finite chance to reproduce and gain some individual fitness for workers, at some future point of time. Wasps may not be similar in their reproductive abilities and those who are less fertile might be joining others who are more fertile. Testing such a hypothesis would require that individuals who have chosen to be subordinate cofoundresses in multiple foundress associations are forced to nest alone. During this study a total of 77 nests was monitored. Cofoundresses forced to nest alone had significantly lower productivity than natural solitary foundresses and also queens of multiple foundress nests who were forced to nest alone. This suggested that wasps are not similar either in their reproductive ability or brood rearing ability or both. To ascertain which of the factors was responsible for lower productivity in cofoundresses, productivity of wasps isolated into laboratory cages was compared. There was no significant difference in the productivity of isolated cofoundresses and isolated queens. This suggests that wasps are not subfertile per se but probably differ in their foraging and brood rearing abilities. The certainty with which resources are brought into the nest and therefore, the certainty with which the mean per capita productivity is attained, provides an automatic benefit of group living according to the central limit theorem. This prediction was also tested. The coefficient of variation of mean per capita productivity decreased significantly with increasing foundress numbers. Behavioural observations on another 36 colonies, with different number of adults, showed that the coefficient of variation of food brought to the nest and the rate at which larvae were fed, decreased significantly with increasing number of adults. A computer simulation was used to find out the effect of group size on the variance in feed larva. Assuming that larvae cannot be starved for too long and cannot utilize more than a certain amount of food at a time, the fitness of larvae was found to increase with an increase in the number of adults attending the nest. Previous work on R. marginata has been largely confined to postemergence colonies. An attempt was made to look at and compare social organization in preemergence colonies with that of postemergence colonies. It was found that the egg layer was not the most dominant animal in the well-established preemergence colonies. There were no detectable differences in the social organization of the preemergence colonies (of this study) with that of postemergence colonies of the earlier studies. Perhaps my conclusions drawn from studying preemergence colonies are therefore applicable more widely to the species. It can be concluded that the apparent increased fitness of the worker strategy over solitary foundress strategy does not come from any increase in per capita productivity, but comes instead from (i) the greater predictability with which the mean per capita productivity is attained in larger colonies, (ii) the lower probabilities of usurpation of larger colonies, (iii) queen turnovers that provide opportunities for workers in multiple foundress colonies to gain some direct individual fitness and (iv) the lower brood rearing abilities of workers in multiple foundress nests that make the worker strategy the best of a bad job.