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At least 19 recordsLinked to original sources
PubMed2005

Psychological altruism vs. biological altruism: narrowing the gap with the Baldwin effect.

This paper defends the position that the supposed gap between biological altruism and psychological altruism is not nearly as wide as some scholars (e.g., Elliott Sober) insist. Crucial to this defense is the use of James Mark Baldwin's concepts of "organic selection"and "social heredity" to assist in revealing that the gap between biological and psychological altruism is more of a small lacuna. Specifically, this paper argues that ontogenetic behavioral adjustments, which are crucial to individual survival and reproduction, are also crucial to species survival. In particular, it is argued that human psychological altruism is produced and maintained by various sorts of mimicry and self-reflection in the aid of both individual and species survival. The upshot of this analysis is that it is possible to offer an account of psychological altruism that is closely tethered to biological altruism without reducing entirely the former to the latter.

Altruism↗
PubMed2004

Sex causes altruism. Altruism causes sex. Maybe.

This study presents a mathematical model in which the fitness of an individual depends on the individual's genotype (individual effects) and on the genotypes of other members of the individual's local group (group effects). The findings suggest that, if phenotypes are a result of complex interactions between genes at different loci, then fitness-enhancing group effects may become common in sexual populations. The spread of fitness-enhancing group effects is facilitated when environmental conditions sometimes deteriorate temporarily. This is so even if the genotypes with the highest group effects also tend to have relatively low individual effects. In this sense, the process described here can lead to the evolution of altruism. By contrast, when populations are asexual it appears that group effects are much less important in determining the outcome of evolution. Thus, in nature, asexual populations may tend to be characterized by more antagonistic interactions than those that typically prevail when reproduction is sexual. This might help to explain why asexual lineages are prone to rapid extinction.

Altruism↗
PubMed2001

Normal and pathological altruism.

The psychoanalytic literature on altruism is sparse, although much has been written on this topic from a sociobiological perspective. Freud (1917) first described the concept in "Libido Theory and Narcissism." In 1946 Anna Freud coined the term "altruistic surrender" to describe the psychodynamics of altruistic behavior in a group of inhibited individuals who were neurotically driven to do good for others. The usefulness and clinical applicability of this formulation, in conjunction with the frequent coexistence of masochism and altruism, encouraged psychoanalysts to regard all forms of altruism as having masochistic underpinnings. Since then, there has been a conflation of the two concepts in much of the analytic literature. This paper reexamines the psychoanalytic understanding of altruism and proposes an expansion of the concept to include a normal form. Five types of altruism are described: protoaltruism, generative altruism, conflicted altruism, pseudoaltruism, and psychotic altruism. Protoaltruism has biological roots and can be observed in animals. In humans, protoaltruism includes maternal and paternal nurturing and protectiveness. Generative altruism is the nonconflictual pleasure in fostering the success and/or welfare of another. Conflicted altruism is generative altruism that is drawn into conflict, but in which the pleasure and satisfaction of another (a proxy) is actually enjoyed. Pseudoaltruism originates in conflict and serves as a defensive cloak for underlying sadomasochism. Psychotic altruism is defined as the sometimes bizarre forms of caretaking behavior and associated self-denial seen in psychotic individuals, and often based on delusion. We consider Anna Freud's altruistic surrender to combine features of both conflict-laden altruism and pseudoaltruism. Two clinical illustrations are discussed.

Altruism↗
PubMed2006

Lower group productivity under kin-selected reproductive altruism.

Hamilton's rule provides the foundation for understanding the genetic evolution of social behavior, showing that altruism is favored by increased relatedness and increased productivity of altruists. But how likely is it that a new altruistic mutation will satisfy Hamilton's rule by increasing the reproductive efficiency of the group? Altruism per se does not improve efficiency, and hence we would not expect a typical altruistic mutation to increase the mean productivity of the population. We examined the conditions under which a mutation causing reproductive altruism can spread when it does not increase productivity. We considered a population divided into temporary groups of genetically similar individuals (typically family groups). We show that the spread of altruism requires a pleiotropic link between altruism and enhanced productivity in diploid organisms, but not in haplodiploid organisms such as Hymenoptera. This result provides a novel biological understanding of the barrier to the spread of reproductive altruism in diploids. In haplodiploid organisms, altruism within families that lowers productivity may spread, provided daughters sacrifice their own reproduction to raise full-sisters. We verified our results using three single-locus genetic models that explore a range of the possible reproductive costs of helping. The advantage of female-to-female altruism in haplodiploids is a well-known prediction of Hamilton's rule, but its importance in relaxing the linkage between altruism and efficiency has not been explored. We discuss the possible role of such unproductive altruism in the origins of sociality. We also note that each model predicts a large region of parameter space were polymorphism between altruism and selfishness is maintained, a pattern independent of dominance.

Altruism↗
PubMed1978

Altruism: its characteristics and evolution.

Altruism is a group phenomenon in which some genes or individuals, which must be presumed to be selfish, benefit others at cost to themselves. The presumption of selfishness and the fact of altruism are reconciled by kin-group selection and by reciprocal altruism. Kin-group selection is clearly visible only in special cases; its role even among social insects may be overestimated; it is probably usually inhibited by competition. However, reciprocal altruism is ubiquitous. All altruism is: (i) potentially reciprocal; (ii) potentially profitable to altruists as well as to recipients; (iii) environmentally determined, usually by position of individuals in group or environmental situations; and (iv) a net-gain lottery. These generalizations are illustrated by four idealized cases; the difficulty of applying them to real cases is illustrated by alarm-calling in groups of birds. Although altruism is a group phenomenon, it evolves by individual selection, by processes equivalent to co-evolutions. Its evolution is: (i) opposed by competition; (ii) costly, complex, and slow, and tending to produce an imprecise flexible altruism rather than a precisely detailed one; and (iii) supplemented by group selection (differential extinction of groups). That altruism in human beings conforms to these generalizations is a good working hypothesis. However, analysis does not "take the altruism out of (human) altruism." Humans do not calculate it, but behave altruistically because they have human altruistic emotions.

Altruism↗
PubMed2003

The adaptive dynamics of altruism in spatially heterogeneous populations.

We study the spatial adaptive dynamics of a continuous trait that measures individual investment in altruism. Our study is based on an ecological model of a spatially heterogeneous population from which we derive an appropriate measure of fitness. The analysis of this fitness measure uncovers three different selective processes controlling the evolution of altruism: the direct physiological cost, the indirect genetic benefits of cooperative interactions, and the indirect genetic costs of competition for space. In our model, habitat structure and a continuous life cycle makes the cost of competing for space with relatives negligible. Our study yields a classification of adaptive patterns of altruism according to the shape of the costs of altruism (with decelerating, linear, or accelerating dependence on the investment in altruism). The invasion of altruism occurs readily in species with accelerating costs, but large mutations are critical for altruism to evolve in selfish species with decelerating costs. Strict selfishness is maintained by natural selection only under very restricted conditions. In species with rapidly accelerating costs, adaptation leads to an evolutionarily stable rate of investment in altruism that decreases smoothly with the level of mobility. A rather different adaptive pattern emerges in species with slowly accelerating costs: high altruism evolves at low mobility, whereas a quasi-selfish state is promoted in more mobile species. The high adaptive level of altruism can be predicted solely from habitat connectedness and physiological parameters that characterize the pattern of cost. We also show that environmental changes that cause increased mobility in those highly altruistic species can beget selection-driven self-extinction, which may contribute to the rarity of social species.

Adaptation, Physiological↗
PubMed2006

Non-reciprocal altruism may be attributable to hyperbolicity in social discounting function.

Humans show altruism even for chance acquaintances whom they will never meet again (non-reciprocal altruism). With respect to evolutionary and economic perspectives, reciprocal altruism is not actually puzzling, because reciprocal altruism maximizes subjects' benefit/fitness in the long run; while non-reciprocal (pure) altruism still presents a challenge to evolutionary biology and neuroeconomics. Understanding neuropsychological bases of non-reciprocal altruism/generosity for unrelated people is also important for neuropsychiatry, because several types of impulsive psychiatrics (e.g., social phobia, substance abusers, psychopaths) often have reduced altruism/generosity for other people, which is associated with their problematic/impulsive social behavior. Regarding the relationship between impulsivity and reciprocal altruism, it has been shown that subjects who are impulsive in intertemporal choice (having a large time-discounting rate) have low degrees of reciprocal altruism, which is in line with economic theories and neuropharmacologically treatable with serotonin/norepinephrine reuptake inhibitors. However, little is known regarding the relationship between non-reciprocal altruism and discounting behavior, and neuropsychological processing underlying the relationship. Recently, Jones and Rachlin reported that generosity for other individuals with different social distances follows a hyperbolic discounting function, which has been employed to describe inconsistent time-discounting. In this study, I propose that non-reciprocal (pure) altruism may be, at least partially, attributable to hyperbolicity of a social discounting function (inconsistency in "interpersonal choice"). Neuropsychological mechanisms underlying interpersonally-inconsistent social discounting and possible implications for neuropsychopharmacological treatments for impulsive psychiatrics' problematic social behavior are discussed.

Altruism↗
PubMed2004

Strong altruism can evolve in randomly formed groups.

Although the conditions under which altruistic behaviors evolve continue to be vigorously debated, there is general agreement that altruistic traits involving an absolute cost to altruists (strong altruism) cannot evolve when populations are structured with randomly formed groups. This conclusion implies that the evolution of such traits depends upon special environmental conditions or additional organismic capabilities that enable altruists to interact with each other more than would be expected with random grouping. Here we show, using both analytic and simulation results, that the positive assortment necessary for strong altruism to evolve does not require these additional mechanisms, but merely that randomly formed groups exist for more than one generation. Conditions favoring the selection of altruists, which are absent when random groups initially form, can naturally arise even after a single generation within groups-and even as the proportion of altruists simultaneously decreases. The gains made by altruists in a second generation within groups can more than compensate for the losses suffered in the first and in this way altruism can ratchet up to high levels. This is true even if altruism is initially rare, migration between groups allowed, homogeneous altruist groups prohibited, population growth restricted, or kin selection precluded. Until now random group formation models have neglected the significance of multigenerational groups-even though such groups are a central feature of classic "haystack" models of the evolution of altruism. We also explore the important role that stochasticity (effectively absent in the original infinite models) plays in the evolution of altruism. The fact that strong altruism can increase when groups are periodically and randomly formed suggests that altruism may evolve more readily and in simpler organisms than is generally appreciated.

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PubMed2006

Altruism through beard chromodynamics.

The evolution of altruism, a behaviour that benefits others at one's own fitness expense, poses a darwinian paradox. The paradox is resolved if many interactions are with related individuals so that the benefits of altruism are reaped by copies of the altruistic gene in other individuals, a mechanism called kin selection. However, recognition of altruists could provide an alternative route towards the evolution of altruism. Arguably the simplest recognition system is a conspicuous, heritable tag, such as a green beard. Despite the fact that such genes have been reported, the 'green beard effect' has often been dismissed because it is unlikely that a single gene can code for altruism and a recognizable tag. Here we model the green beard effect and find that if recognition and altruism are always inherited together, the dynamics are highly unstable, leading to the loss of altruism. In contrast, if the effect is caused by loosely coupled separate genes, altruism is facilitated through beard chromodynamics in which many beard colours co-occur. This allows altruism to persist even in weakly structured populations and implies that the green beard effect, in the form of a fluid association of altruistic traits with a recognition tag, can be much more prevalent than hitherto assumed.

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PubMed1986

Socialization and situational influences on sustained altruism.

In this conceptual replication and extension of Rosenhan's study of civil rights activists, the sustained altruism (i.e., help that extends over time) of volunteers at a telephone crisis-counseling agency was examined. Using a prospective format, it was predicted that volunteers with a socialization history of exposure to nurturant parents who modeled altruism (autonomous altruists) would exhibit a greater degree of sustained altruism than those with a history of less nurturant parents who modeled altruism to a lesser degree (normative altruists). The altruism of the normative volunteers, however, was expected to increase given certain situational conditions (here, participation in a highly cohesive training group prior to the actual volunteer activity). As predicted, the rate of sustained altruism of normative volunteers in highly cohesive groups was increased to a level comparable to that of autonomous volunteers, while the altruism of autonomous volunteers was not affected by the training group experience. The implications of these findings for research on altruism and its development, as well as some applications to volunteerism, are discussed.

Adolescent↗
PubMed2004

Adaptive evolution of social traits: origin, trajectories, and correlations of altruism and mobility.

Social behavior involves "staying and helping," two individual attributes that vary considerably among organisms. Investigating the ultimate causes of such variation, this study integrates previously separate lines of research by analyzing the joint evolution of altruism and mobility. We unfold the network of selective pressures and derive how these depend on physiological costs, eco-evolutionary feedbacks, and a complex interaction between the evolving traits. Our analysis highlights habitat saturation, both around individuals (local aggregation) and around unoccupied space (local contention), as the key mediator of altruism and mobility evolution. Once altruism and mobility are allowed to evolve jointly, three general insights emerge. First, the cost of mobility affects the origin of altruism, determining whether and how quickly selfishness is overcome. Second, the cost of altruism determines which of two qualitatively different routes to sociality are taken: an evolutionary reduction of mobility, resulting in higher habitat saturation, is either preceded or followed by the adaptive rise of altruism. Third, contrary to conventional expectations, a positive correlation between evolutionarily stable levels of altruism and mobility can arise; this is expected when comparing populations that evolved under different constraints on mobility or that differ in other life-history traits.

Adaptation, Physiological↗
PubMed2000

The spatial spread of altruism versus the evolutionary response of egoists.

Several recent models have shown that altruism can spread in viscous populations, i.e. in spatially structured populations within which individuals interact only with their immediate neighbours and disperse only over short distances. I first confirm this result with an individual-based model of a viscous population, where an individual can vary its level of investment into a behaviour that is beneficial to its neighbours but costly to itself. Two distinct classes of individuals emerge: egoists with no or very little investment into altruism, and altruists with a high level of investment; intermediate levels of altruism are not maintained. I then extend the model to investigate the consequences of letting interaction and dispersal distances evolve along with altruism. Altruists maintain short distances, while the egoists respond to the spread of altruism by increasing their interaction and dispersal distances. This allows the egoistic individuals to be maintained in the population at a high frequency. Furthermore, the coevolution of investment into altruism and interaction distance can lead to a stable spatial pattern, where stripes of altruists (with local interactions) alternate with stripes of egoists (with far-reaching interactions). Perhaps most importantly, this approach shows that the ease with which altruism spreads in viscous populations is maintained despite countermeasures evolved by egoists.

Altruism↗
PubMed2006

The evolution of altruism between siblings: Hamilton's rule revisited.

This paper explores the validity of Hamilton's rule in the case of other-only altruism in which the benefits are shared by other members of the sibling group excluding the donor. It presents a model of competition between two alleles which code for different kinds of altruism. It derives a simple replicator equation for allele frequencies under conditions of strong selection. This equation does not depend on the size of the sibling group. In mathematical form, the equation is similar to Hamilton's original rule in the case of inbreeding, although the causal mechanism is different. The paper derives a simple criterion to determine whether there will be a polymorphism in which both alleles coexist permanently. Such an event is rare and victory will normally go to the allele with the higher value of 1/2b-c, where b is the total benefit which an offspring confers on its siblings and c is the cost to the donor. The paper also considers how an offspring will behave in particular circumstances. Using a specialized version of the basic model, it shows how, in the absence of polymorphism, natural selection should take the system towards the point of 50% marginal altruism. With this type of altruism, an offspring will perform any act for which the expected cost to the donor is at most half the expected benefit to its siblings. Acts which do not satisfy this criterion are not performed. This accords with Haldane's quip that he would sacrifice his own life for two of his brothers, but not for less. Numerical simulation is used to explore these issues in greater depth. The paper also examines briefly the implications of heterozygote advantage for Hamilton's rule. It concludes with a brief discussion of the connection between other-only altruism and whole-group altruism, in which the donor gains some benefit from its actions.

Altruism↗
PubMed2006

The evolution of altruism: game theory in multilevel selection and inclusive fitness.

Although the prisoner's dilemma (PD) has been used extensively to study reciprocal altruism, here we show that the n-player prisoner's dilemma (NPD) is also central to two other prominent theories of the evolution of altruism: inclusive fitness and multilevel selection. An NPD model captures the essential factors for the evolution of altruism directly in its parameters and integrates important aspects of these two theories such as Hamilton's rule, Simpson's paradox, and the Price covariance equation. The model also suggests a simple interpretation of the Price selection decomposition and an alternative decomposition that is symmetrical and complementary to it. In some situations this alternative shows the temporal changes in within- and between-group selection more clearly than the Price equation. In addition, we provide a new perspective on strong vs. weak altruism by identifying their different underlying game structures (based on absolute fitness) and showing how their evolutionary dynamics are nevertheless similar under selection (based on relative fitness). In contrast to conventional wisdom, the model shows that both strong and weak altruism can evolve in periodically formed random groups of non-conditional strategies if groups are multigenerational. An integrative approach based on the NPD helps unify different perspectives on the evolution of altruism.

Altruism↗
PubMed2002

Altruism and compassion in the health professions: a search for clarity and precision.

This article presents a conceptual model of altruism grounded in compassion in the health professions. The intent is to bring order out of the current conceptual chaos about the meaning and practical operation of these constructs. The theory-based model proposes that altruism is expressed as overt behavior in specific situations that vary in levels of intensity. It assumes that altruism is not a broad-based, cross-situational personal trait; that altruism can be measured objectively; and that altruism can be increased via education, practice and reinforcement. The article concludes by demonstrating the progression from formation of a theory-based conceptual model, development of objective measures, performing systematic research and accumulating an orderly and consensual body of knowledge about altruism grounded in compassion in the health professions.

Altruism↗