The importance of need-altruism and kin-altruism to blood donor behaviour for black and white people

BACKGROUND

Need-altruism (a preference to help people in need) and kin-altruism (a preference to help kin over non-kin) underlie two hypotheses for voluntary blood donation: (i) Need-altruism underlies motivations for volunteer blood donation and (ii) Black people express a stronger preference for kin-altruism, which is a potential barrier to donation. This paper tests these hypotheses and explores how need- and kin-altruism are associated with wider altruistic motivations, barriers, and strategies to encourage donation.

METHODS

We assessed need- and kin-altruism, other mechanisms-of-altruism (e.g., reluctant-altruism), barriers, strategies to encourage donation, donor status, and willingness-to-donate across four groups based on ethnicity (Black; White), nationality (British; Nigerian), and country-of-residence: (i) Black-British people (n = 395), and Black-Nigerian people (ii) in the UK (n = 97) or (iii) across the rest of the world (n = 101), and (v) White-British people in the UK (n = 452). We also sampled a Black-Nigerian Expert group (n = 60).

RESULTS

Need-altruism was higher in donors and associated with willingness-to-donate in non-donors. Levels of kin-altruism did not differ between Black and White people, but need-altruism was lower in Black-British people. Kin-altruism was associated with a preference for incentives, and need-altruism with a preference for recognition (e.g., a thank you) as well as an increased willingness-to-donate for Black non-donors. Need-altruism underlies a blood-donor-cooperative-phenotype.

CONCLUSION

Need-altruism is central to blood donation, in particular recruitment. Lower need-altruism may be a specific barrier for Black-British people. Kin-altruism is important for Black non-donors. The blood donor cooperative phenotype deserves further consideration. Implications for blood services are discussed.

Children are eager to take credit for prosocial acts, and cost affects this tendency

We report two experiments on children's tendency to enhance their reputations through communicative acts. In the experiments, 4-year-olds (N = 120) had the opportunity to inform a social partner that they had helped him in his absence. In a first experiment, we pitted a prosocial act ("Let's help clean up for Doggie!") against an instrumental act ("Let's move these out of our way"). Children in the prosocial condition were quicker to inform their partner of the act and more likely to protest when another individual was given credit for it. In a second experiment, we replicated the prosocial condition but with a new manipulation: high-cost versus low-cost helping. We manipulated both the language surrounding cost (i.e., "This will be pretty tough to clean up" vs. "It will be really easy to clean this up") and how difficult the task itself was. As predicted, children in the high-cost condition were quicker to inform their partner of the act and more likely to take back credit for it. These results suggest that even 4-year-old children make active attempts to elicit positive reputational judgments for their prosocial acts, with cost as a moderating factor.

Warming up cool cooperators

Explaining why someone repeats high-cost cooperation towards non-reciprocating strangers is difficult. Warm glow offers an explanation. We argue that warm glow, as a mechanism to sustain long-term cooperation, cools off over time but can be warmed up with a simple intervention message. We tested our predictions in the context of repeat voluntary blood donation (high-cost helping of a non-reciprocating stranger) across 6 studies: a field-based experiment (n = 5,821) comparing warm-glow and impure-altruism messages; an implementation study comparing a 3-yr pre-implementation period among all first-time donors in Australia (N = 270,353) with a 2-yr post-implementation period (N = 170, 317); and 4 studies (n = 716, 1,124, 932, 1,592) exploring mechanisms. We show that there are relatively warm and cool cooperators, not cooling cooperators. Cooperation among cool cooperators is enhanced by a warm-glow-plus-identity message. Furthermore, the behavioural facilitation of future cooperation, by booking an appointment, is associated with being a warm cooperator. Societal implications are discussed.

Condition-dependent trade-offs maintain honest signalling

How and why animals and humans signal reliably is a key issue in biology and social sciences that needs to be understood to explain the evolution of communication. In situations in which the receiver needs to differentiate between low- and high-quality signallers, once a ruling paradigm, the Handicap Principle has claimed that honest signals have to be costly to produce. Subsequent game theoretical models, however, highlighted that honest signals are not necessarily costly. Honesty is maintained by the potential cost of cheating: by the difference in the marginal benefit to marginal cost for low versus high-quality signallers; i.e. by differential trade-offs. Owing to the difficulties of manipulating signal costs and benefits, there is lack of empirical tests of these predictions. We present the results of a laboratory decision-making experiment with human participants to test the role of equilibrium signal cost and signalling trade-offs for the development of honest communication. We found that the trade-off manipulation had a much higher influence on the reliability of communication than the manipulation of the equilibrium cost of signal. Contrary to the predictions of the Handicap Principle, negative production cost promoted honesty at a very high level in the differential trade-off condition.

Condition-dependent trade-offs maintain honest signalling

How and why animals and humans signal reliably is a key issue in biology and social sciences that needs to be understood to explain the evolution of communication. In situations in which the receiver needs to differentiate between low- and high-quality signallers, once a ruling paradigm, the Handicap Principle has claimed that honest signals have to be costly to produce. Subsequent game theoretical models, however, highlighted that honest signals are not necessarily costly. Honesty is maintained by the potential cost of cheating: by the difference in the marginal benefit to marginal cost for low versus high-quality signallers; i.e. by differential trade-offs. Owing to the difficulties of manipulating signal costs and benefits, there is lack of empirical tests of these predictions. We present the results of a laboratory decision-making experiment with human participants to test the role of equilibrium signal cost and signalling trade-offs for the development of honest communication. We found that the trade-off manipulation had a much higher influence on the reliability of communication than the manipulation of the equilibrium cost of signal. Contrary to the predictions of the Handicap Principle, negative production cost promoted honesty at a very high level in the differential trade-off condition.

Advertising cooperative phenotype through costly signals facilitates collective action

Around the world, people engage in practices that involve self-inflicted pain and apparently wasted resources. Researchers theorized that these practices help stabilize within-group cooperation by assorting individuals committed to collective action. While this proposition was previously studied using existing religious practices, we provide a controlled framework for an experimental investigation of various predictions derived from this theory. We recruited 372 university students in the Czech Republic who were randomly assigned into either a high-cost or low-cost condition and then chose to play a public goods game (PGG) either in a group that wastes money to signal commitment to high contributions in the game or to play in the group without such signals. We predicted that cooperators would assort in the high-cost revealed group and that, despite these costs, they would contribute more to the common pool and earn larger individual rewards over five iterations of PGG compared with the concealed group and participants in the low-cost condition. The results showed that the assortment of cooperators was more effective in the high-cost condition and translated into larger contributions of the remaining endowment to the common pool, but participants in the low-cost revealed group earned the most. We conclude that costly signals can serve as an imperfect assorting mechanism, but the size of the costs needs to be carefully balanced with potential benefits to be profitable.

The benefits of being seen to help others: indirect reciprocity and reputation-based partner choice

When one individual helps another, it benefits the recipient and may also gain a reputation for being cooperative. This may induce others to favour the helper in subsequent interactions, so investing in being seen to help others may be adaptive. The best-known mechanism for this is indirect reciprocity (IR), in which the profit comes from an observer who pays a cost to benefit the original helper. IR has attracted considerable theoretical and empirical interest, but it is not the only way in which cooperative reputations can bring benefits. Signalling theory proposes that paying a cost to benefit others is a strategic investment which benefits the signaller through changing receiver behaviour, in particular by being more likely to choose the signaller as a partner. This reputation-based partner choice can result in competitive helping whereby those who help are favoured as partners. These theories have been confused in the literature. We therefore set out the assumptions, the mechanisms and the predictions of each theory for how developing a cooperative reputation can be adaptive. The benefits of being seen to be cooperative may have been a major driver of sociality, especially in humans. This article is part of the theme issue 'The language of cooperation: reputation and honest signalling'.

A branded bandage is worth a thousand words: blood branded bandages signal men's generosity and morality

BACKGROUND AND OBJECTIVE

Recruiting and retaining male donors remain an ongoing challenge for blood collection agencies. Research suggests that interventions based on costly signalling theory that allows donors to unobtrusively but publicly signal their donor status may be effective. However, what functions as such a signal and how it is interpreted has not been determined.

MATERIALS AND METHODS

A total of 242 Australian residents (127 female; 115 male) recruited through an online research platform rated their perceptions of a male target wearing (a) no bandage, (b) a regular unmarked bandage or (c) a blood donor branded bandage.

RESULTS

The target wearing a blood donor branded bandage was rated as significantly more generous by female participants and moral compared to both the target who wore no bandage and the target wearing a regular unmarked bandage. The target wearing the unmarked bandage was perceived as significantly less healthy and competent compared to the target not wearing a bandage.

CONCLUSION

A public signal of public donor status conveys the generosity and morality of the wearer. The bandage applied to donors after they have donated can act as such an effective signal, but only when these bandages are clearly branded as resulting from donating blood.

Giving Guys Get the Girls: Men Appear More Desirable to the Opposite Sex When Displaying Costly Donations to the Homeless

One of the evolutionary adaptive benefits of altruism may be that it acts as an honest (reliable) signal of men’s mate quality. In this study, 285 female participants were shown one of three video scenarios in which a male target took £30 out of a cash machine (ATM) and gave either a lot (£30), a little (£1), or nothing to a homeless man. The participants rated the male target on his attractiveness, their short- and long-term mate preferences towards him, and the degree to which they thought he was likely to possess various parenting qualities. The results showed that, regardless of whether the man was described as rich or poor, participants rated him as being more attractive when he donated money, but only when the donation was costly (£30). In addition, altruism was shown to be important in long-term, but not short-term mate choice, and displays of altruism were associated with positive parenting qualities. It is argued that displays of altruism act as a reliable (honest) mate signal for a potential long-term parental partner.

Evolution of costly signaling and partial cooperation

Two seemingly unrelated, but fundamental challenges in evolutionary theory, are the evolution of costly signals and costly cooperative traits, both expected to reduce an individual’s fitness and diminish by natural selection. Here, by considering a well mixed population of individuals who produce signals and decide on their strategies in a game they play, based on the signals, we show that costly signals and costly cooperative strategies can co-evolve as a result of internal dynamics of the system. Costly signals evolve, despite their apparent cost, due to a favorable cooperative response they elicit. This favorable strategic response can be quantified in a fitness term which governs the distribution of costly signals better than their apparent cost. In the same way, cooperative strategies evolve as they can reach a high fitness due to the internal dynamics of the systems.

Content, cost, and context: A framework for understanding human signaling systems

Humans frequently perform extravagant and seemingly costly behaviors, such as widely sharing hunted resources, erecting conspicuous monumental structures, and performing dramatic acts of religious devotion. Evolutionary anthropologists and archeologists have used signaling theory to explain the function of such displays, drawing inspiration from behavioral ecology, economics, and the social sciences. While signaling theory is broadly aimed at explaining honest communication, it has come to be strongly associated with the handicap principle, which proposes that such costly extravagance is in fact an adaptation for signal reliability. Most empirical studies of signaling theory have focused on obviously costly acts, and consequently anthropologists have likely overlooked a wide range of signals that also promote reliable communication. Here, we build on recent developments in signaling theory and animal communication, developing an updated framework that highlights the diversity of signal contents, costs, contexts, and reliability mechanisms present within human signaling systems. By broadening the perspective of signaling theory in human systems, we strive to identify promising areas for further empirical and theoretical work.

Psychosocial characteristics of blood donors influence their voluntary nonmedical lapse

BACKGROUND

Approximately 10% of Dutch donors lapse yearly. Common reasons are nonvoluntary medical issues (e.g., low hemoglobin), reaching the upper age limit, and voluntary (e.g., own request, nonresponse). Little is known about predictors of voluntary noncompliance (lapses). Psychosocial characteristics have been linked to various health behaviors, including voluntary noncompliance. Hence, we investigated whether psychosocial characteristics, measured before the first donation, similarly predict subsequent voluntary nonmedical lapse.

STUDY DESIGN AND METHODS

New donors (n = 4861) randomly received a blood donation survey between July 2008 and March 2009, before their first appointment at the blood bank. Voluntary lapses included personal reasons, nonresponse to invitations, donor who could not be reached, and no show. Univariate and multivariate Cox regression models of lapse on psychosocial characteristics and confounders (e.g., demographics) were estimated.

RESULTS

Of 2964 donors who took the questionnaire, more than one-third (36.5%) had voluntarily lapsed due to nonmedical reasons by 2016. Univariate regression showed that lapse negatively associated with norms, attitudes, and intentions toward blood donation; self-efficacy; and more donation experience. Lapse positively associated with anxiety. Multivariate Cox models showed that lapse was primarily driven by anxiety and need for information.

CONCLUSION

Certain psychosocial characteristics increase risks of voluntary lapse. Especially donors with higher donation anxiety had increased lapsing risks. They might benefit from extra attention during donation. Donors with more information need or wish about procedure and patients were less likely to lapse, indicating that binding with the blood bank might prevent lapse. Generally, this study showed that donor lapse and donor return are determined by different psychosocial factors not just the reverse of each other.

Costless and Costly Prosociality: Correspondence Among Personality Traits, Economic Preferences, and Real-World Prosociality

Prosociality can either be costly (e.g., donating to charity) or costless (e.g., posthumous organ donation). Whereas links between personality and costly prosociality have been explored, links with costless prosociality and personality are at present unknown. We address this in two studies: Study 1 ( N = 200) confirms the distinction between costless and costly prosociality based on willingness to engage with health and nonhealth prosociality. Study 2, using data from four samples (student and community; N = 733) shows, across incentivized and hypothetical economic games to assess costless (generosity game [GG]) and costly (dictator game [DG]) prosociality, that organ donor behavior was linked to greater allocations in the GG and that charity/volunteering behavior was linked to greater allocations in the DG. Costless and costly prosocialities are associated with different personality traits (e.g., costly with politeness and compassion and costless with intellect). Implications for cooperative phenotypes and recruiting organ donors are discussed.

Multiple reputation domains and cooperative behaviour in two Latin American communities

Reputations are a ubiquitous feature of human social life, and a large literature has been dedicated to explaining the relationship between prosocial reputations and cooperation in social dilemmas. However, humans form reputations in domains other than prosociality, such as economic competency that could affect cooperation. To date, no research has evaluated the relative effects of multiple reputation domains on cooperation. To bridge this gap, we analyse how prosocial and competency reputations affect cooperation in two Latin American communities (Bwa Mawego, Dominica, and Pucucanchita, Peru) across a number of social contexts (Dominica: labour contracting, labour exchange and conjugal partnership formation; Peru: agricultural and health advice network size). First, we examine the behavioural correlates of prosocial and competency reputations. Following, we analyse whether prosocial, competency, or both reputation domains explain the flow of cooperative benefits within the two communities. Our analyses suggest that (i) although some behaviours affect both reputation domains simultaneously, each reputation domain has a unique behavioural signature; and (ii) competency reputations affect cooperation across a greater number of social contexts compared to prosocial reputations. Results are contextualized with reference to the social markets in which behaviour is embedded and a call for greater theory development is stressed.

Competitive morality

Baumard et al. argue that partner choice leads to fairness and mutualism, which then form the basis for morality. I comment that mutualism takes us only so far, and I apply the theory of competitive altruism in arguing how strategic investment in behaviours which make one a desirable partner may drive moral conduct.