critical essay

� Abstract—Within the domain of prosocial behavior, the most

intense debate centers on the degree to which behavior is the result of an altruistic personality in combination with situational, cultural, gender, and contextual factors. In the recent years, attempts to narrow the parameters of this discussion have focused on subsets of prosocial behavior such as: altruism versus self-interest, helping behaviors sustained over time versus one-time events, personality variables versus situational context, the origins of empathy, as well as others related topics. Prosocial behavior is not an organized topic confined within one discipline. A review of the literature reveals that psychologists, philosophers, economists, sociologists, and others all have distinct and often conflicting points of view. More conceptual work on social competence and the development of interpersonal competence in peer relationships is relevant to better understanding of prosocial development. It would benefit the broader field of developmental sciences, if the boundaries among content areas had more fluidity.

Keywords—Altruism, Empathy, Poignancy, Predisposition, Prosocial Behavior, Tempered Radical.

I. INTRODUCTION HE term prosocial behavior was introduced in the early 1970’s, in the aftermath of the Kitty Genovese murder, in

New York (Kohn, 1990). One definition represents prosocial behavior as “any act performed with the goal of benefiting another person” (Aronson, Wilson, & Akert, 2004). Interestingly, this is not an organized topic confined to a single discipline. Even a superficial review of the literature tends to reveal that: psychologists, philosophers, economists, sociobiologists, and others all have distinct and often conflicting points of view. If one accepts the Aronson et al. (1996) definition, probing question of why prosocial literature seems to bypass other helping behaviors, such as certain forms of advocacy and activism becomes relevant. Kohn (1990, p. 6) contends that “biological determinism”

Anna Whitehead, MPA, MA, Assistant Campus Center Director, Park University,639 Merritt St.P.O. Box 16276 Fort Bliss, TX 79906 USA,Tel: (915) 832-3306, Email: [email protected]

Dr. Steve Hallman, D.B.A. Associate Professor & Assoc MBA Director,Park University, 911 Main Suite 928 Kansas City, MO 64105 USA,Tel: (816) 559- 5688, or (816) 550-9645 cell E-mail: [email protected] ,[email protected]

Dr Michel Plaisent, full professor, dept Management and technology, university of quebec in Montreal , 1 514 987-3000 x4253, [email protected]

Dr Prosper Bernard, full professor, dept Management and technology, university of quebec in Montreal , 1 514 987-4250, [email protected]

is still a dominant factor in the way that both researchers and the public perceive behavior. He suggests the prevailing paradigm in Western societies, and particularly in America in the 20th century, is that our behavior is genetically,” as an astonishing array of behaviors are seen as being “just human nature.” Those Aspects of social and economic structure that privilege some, over others, are too often justified, as both correct and inevitable. Kohn (1990) traces this point of view back to the history of philosophical and religious thought. The Oliners (1988), among others researchers and philosophers, comment on Freud’s description of the natural viciousness of man, which is just barely contained behind “public persona.” From a psychoanalytic view, the constraints imposed by society teach individuals, to curb our instinctive aggressiveness and help others. The psychoanalytic view suggests that such help is not altruistic, since it is embedded in satisfying the self. This view further appears to align with traditional religious teaching about “wickedness and evil.” Kohn (1990) suggests the position of simple-minded “good versus evil” is a false dichotomy, unsupported by facts. Kohn (1990) also proposes that a more useful frame “human nature” argument is in through recognizing several key constraints. Kohn (1990, p. 7) suggests human nature is itself a social product, and that there is no nature without an environment and a cultural context. “The real alternative to biological determinism is human choice.” He further notes that it is erroneous to assume that genetically inherited traits are fixed, and not subject to modification. His view implies that the possibility for change may lie within biology itself. In lieu of this concept, one must ask; if it is not obvious that self-interest is governing our behavior, then what does guide our choices?

II. “FEED YOUR MIND” Daloz (1996) and his colleagues, illuminates this notion

with poignancy. Daloz and his contemporaries selected to extensively study100 individuals whose lives demonstrate a “commitment to the common good.” study. In Their conclusion, notes “While no single experience can ensure a committed life, we found one common thread in the life experience of everyone we studied; we call this a constructive engagement with otherness.” This summarization refers to encounters or interactions with others, who are in some way

The Need for Semantical Understanding of Prosocial Behavior in the Workplace

Anna Whitehead, MPA, Dr. Steve Hallman, Dr. Michel Plaisent, and Dr. Prosper Bernard

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different from one’s family or tribe. Such interaction tends to challenge rigid boundaries of “me” and “mine,” thereby opening a larger sense of the world.

While it might be argued that Daloz et al.’s observation is no different from the notion of “perspective-taking” mentioned within literature focusing on the development of empathy, the explication is portrayed in an interesting way. Noting the role of “meaning-making” at the core of living and melded with the constant interplay between self and others, they write, “We will act in a manner, congruent with how we ultimately make meaning, with what we finally can and cannot trust, with what we feel we can and cannot do” (Daloz, Keen, Keen, & Parks, 1996). This leads to the concept of a “public parent,” defined as a parental figure who conveys concern and care for the wider community. In their study, more than half of the people had at least one such parent, who helped to shape the notion of prosocial behavior in their mind.

III. PUBLIC PARENT The notion of “public parent” is further confirmed by

Oliner & Oliner (1988), who stated: “The differences between the basic values and world views of rescuers and non-rescuers can be traced in part to their parents’ significantly different views about appropriate standards and the importance of self and others” (Oliner & Oliner, 1988).

Interestingly, “parents of the rescuers” relied significantly less on physical punishment when children behaved badly with all others. Using explanations and reasoning, parents encouraged children to appreciate others’ feelings. The Oliners (1988) further theorize, “When adults voluntarily abdicate the use of power in favor of explanation, they are modeling appropriate behavior toward the weak, on the part of the powerful.” While equally unconventional as non-rescuer parents, the parents of rescuers were significantly less likely to emphasize “obedience.”

Eisenberg, specialist in socialization, moral and emotional development, socio-emotional competence, altruism, empathy, and gender role development has been conducting research on empathy and the development of prosocial behavior since the early 1980’s. Eisenberg was particularly interested in comparing the relationship of prosocial moral reasoning, to prosocial behavior, at various ages. She concluded the study “results strongly support the view that there is a prosocial personality disposition in at least middle-class individuals in Western culture” (Eisenberg, Guthrie, Cumberland, & Murphy, 2002, p. 3). Perhaps more interestingly, she posits, “stable individual differences in empathy – related responding emerge by childhood and likely account for some consistency over time” (Eisenberg et al., 2002).

In an earlier article, Eisenberg stressed a point that Kohn, the Oliners, and others make. Eisenberg (et al., 2002) noted that while empathy is positively related to prosocial behavior.

It does not necessarily imply that empathy will result in prosocial actions (Eisenberg & Strayer, 1987). The relationship between the two is “neither direct nor inevitable” (Eisenberg & Strayer, 1987). Kohn noted that, “empathy may lead to helping, but helping does not imply empathy” (Kohn, 1990) It has been found that “predisposition” tends to represent an inclination toward a given type of response, and not an absolute or constant behavior within every circumstance (Oliner & Oliner, 1988). De Cremer, Mayer, Dijke, Schouten, and Bardes (2009) argue that self-sacrificial leaders motivate followers to display similar positive behaviors because these leaders stimulate goals and values that inspire self-interest for group welfare, and higher ethical standards to fulfill obligations and moral duties. Empathic values motivate followers to immolate leader’s self-sacrifice by displaying prosocial behaviors. In the grand scheme of prosocial behaviors, the difficulties surrounding the definition and measurement of a concept, such as empathy mixed with the role it does or does not play constrains even the best attempts to examine the complex subject.

Eisenberg and Miller summarize many of these issues in their review of seven types of measures that purport to assess the relationship between sympathy, empathy, and altruism, with both children and adults. They conclude, “The research concerning sympathy and empathy lacks much in the way of both conceptual and methodological sophistication” (Eisenberg & Miller, 1987, p. 292).

Another perspective shared by behavioral researchers is the recognition that people engaged in prosocial behavior over time, generally have the ability to see the bigger picture. De Cremer et al. (2009) also note self-sacrificial leaders often forgo personal interests and highlight the importance of the mission as essential to the purpose of the group is. Astin and Leland studied a thirty year history of seventy-seven women leaders working toward educational and social justice for women in higher education. They surmise that the ability to frame the issues systemically was a powerful driver for these women leaders, as they could see that a sustained and visionary effort would be required. “They appeared to bring to women’s concerns not only a sense of justice, but also their capacity to: conceptualize, to generate ideas, to see the “bigger picture,” and to seize opportunities to elevate their ideas into tangible formats” (Astin & Leland, 1991).

The Oliners (1988), though using a different linguistic frame refer to this same notion. They discuss the complex mechanics that needed planning to safely maintain even one person in hiding, with food so scare and with informers everywhere. Highlighting the ability of non-Jewish citizens to conceptualize that the “Jews” were in a situation not of their own making, as the propaganda suggested, the researchers inadvertently address social justice. Daloz et. al. (1996), discuss the crucial nature of systemic thought in the context of the complexities of modern life. In their study, most of their participants reject as insufficient, an

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interpersonal frame that may hold a measure of truth, but “is limited and often distorted in the absence of a larger, systemic perspective” (Daloz et al., 1996). This awareness contributes to prosocial behavior and allows those engaged to be effective despite discouragement and difficulty.

It is important to note that most research would seem to agree that the decision to help: is a complex interaction between the prosocial disposition and the specific circumstances at hand, which may include an understanding of the need, the risks involved, resources required, and other potential variables.

IV. GROUP ADVOCACY A second area of research focuses on helping behaviors,

primarily within the context of contemporary business organizations or health-care. This venue of research appears inclined to view situational factors such as influencing a person’s choice to act, rather than the group itself.

Harquail (1996) investigated the advocacy behavior of sixty-one women in one organization. Participants represented approximately 51% of all salaried employees. In Harquail’s study, advocates were defined as those who attempted to change the distribution of influences, resources, and power within that organization to the benefit of group members. Her study suggests that stronger social identification leads to group advocacy, and that “feeling responsible to the group” (1996) represents a perspective somewhere between social identification and advocacy (Harquail, 1996). Harquail applied the “Proactivity Scale” devised by Bateman and Crant in 1993 to measure the predisposition to take action. On average, participants in the Harquail’s (1996) study were slightly proactive. Specifically, advocacy behaviors in the study included hiring women for key roles, addressing pay equivalence problems, providing support for working mothers in terms of more liberal policies on flextime and maternity leave, and explicit action against stereotyping.

Meyerson and Scully (1995) advance a related notion in their framing of the “tempered radical.” They suggest that a tempered radical is an individual who identifies with and is committed to an organization, as well as to a cause or ideology that may be “at odds” with the dominant culture of that organization. The tempered radical, angered by injustice, challenges the status quo, while carefully navigating the potential shoals and rapids of organizational life. (1995)These individuals face a continuous struggle between personal and professional identities. Often, using their own experience as an example, these researchers describe their struggle as strong feminists in both graduate business schools and business organizations, where they may work. In sharing their personal insight, they honor the often-conflicting aims and purposes of each side of their own identity.

In their view, a tempered radical’s experience of “marginality and biculturalism,” can provide the recognition

that issues need to be addressed (Meyerson & Scully, 1995). According to the researchers, this role is difficult to maintain over a long period. In part, the difficulty arises as pressures of each side attempt to embrace more fully its position, often to the exclusion of others.

While the existence of “tempered radicalism” exists in modern organizations, the authors do not suggest, in any way, how or why this particular group of “change agents” forms. Since many people enter organizational life with multiple and conflicting identities, this research does not currently to address the question of why some people would choose the risk of engaging in prosocial behavior. Though the research is descriptive, it is not particularly clarifying.

Ashford, Rothbard, Piderit, & Dutton, (1998) study reviewed the question of breaking point. In other words, under what conditions women would raise and promote gender-equity issues in their work organizations. This study expanded upon the definition of issue selling developed earlier by Dutton and Ashford (1998). When calling the organization’s attention to trends and events having implications for organizational performance, one is issue selling. Author’s data suggests the perceived favorability of the organizational context fosters a willingness to sell gender- equity issues within a given organization. The discussion indicates a trusting relationship with critical decision makers and a high degree of organizational support for employee participation, encouraged pro-social behaviors, and enhanced the perception of “selling success.” In addition, a favorable context diminished the degree of potential image risks perceived by the participants. The researchers found individual hypothesized differences did not affect the decision to sell gender-equity issues. However, they did qualify their findings by noting they may not have selected the right dispositional factors. They also reported that their data confirm Harquail’s findings regarding the positive relationship between: 1) strength of social identification with women, and 2) advocacy on their behalf (Ashford, Rothbard, Piderit, & Dutton, 1998).

V. NATURALISTIC STUDIES Spacapan and Oskamp (1992) looked at helping behaviors

in a quite different context than did previous researchers. They examined a group of what they term “naturalistic studies,” by which “helping behavior arises in real-life, primarily in the context of on-going personal relationships. They point out the lack of clarity in the conceptualization of “help” across social psychology research, suggesting that adoption of three-category classification of: 1) emotional, 2) informational, and 3) instrumental support would be useful. They also note that depending on the nature of the problem, in addition to the type of support, specifying “particular sources of support” may be more helpful.

Wills (1992) argues that it is the context of personal relationships, which accounts for differences observed

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between lab and field studies, when individuals seek help. He also argues that the perceived ability of the seeker to reciprocate, based upon a history of sharing or intimacy, the existence of communal norms (as opposed to an exchange orientation), and the existence of multiple sources of support are some of the factors that generally lead to higher amounts of help-seeking, than seen in typical lab settings (Wills, 1992). In addition, he reports that aside from serious medical problems, people have a strong preference for informal sources of help stemming from spouses or friends, for most types of situations. “Similarity” between the seeker and the person he or she seeks help from, is another important consideration.

VI. CONCLUSION The study of prosocial behavior would benefit from greater

integration with conceptual work on related issues. Prosocial behavior could be considered in a manner similar to most interpersonal behaviors-in terms of its appropriateness as it applies to social and personal outcomes. In many, settings, prosocial behavior is a socially appropriate behavior. Increased research and conceptual work focusing on social competence and the development of interpersonal competence in peer relationships is relevant to better understanding of prosocial development.

There are many underlying issues that frame the debate of prosocial behavior within various fields. The literature implies prosocial behavior of leaders positively affects those under their guidance. In management for example, it benefits employee moral, organizational development and culture. The “want” in leaders to inspire and help their subordinates to be successful builds strong interpersonal, growth inspired effective relationships. Clearly that the question is “How can we encourage people to act from their prosocial/“brighter side”? Certainly, it these behaviors will come forth by recognizing that it may be a highly complex and somewhat unpredictable process at best.

Finally, not only has the field of prosocial behavior been relatively intellectually remote from relevant literature on other topics, but investigators studying other issues (e.g., psychopathology, information processing, peer relationships, academic success) leading to insufficient in-depth findings in the domain of prosocial development The broader field of developmental sciences would benefit if the semantic boundaries between content areas demonstrated more fluidity.

REFERENCES [1] Aronson, E., Wilson, T., & Akert, R. (2004). Social Psychology, Media

and Research Update (Fourth ed.). Upper Saddle River, N.J.: Pearson Education.

[2] Ashford, S., Rothbard, N., Piderit, S., & Dutton, J.E. (1998). Out on a limb: the role of context and impression management in selling gender- equity issues. Administrative Science Quarterly, 43(1), 23-58.

[3] Astin, H.S., & Leland, C. (1991). Women of Influence, Women of Vision. San Francisco: Jossey-Bass.

[4] Daloz, L.A., Keen, C., Keen, J., & Parks, S.D. (1996). Common fire: Leading lives of commitment in a complex world. Boston: Beacon Press.

[5] De Cremer, D., Mayer, D., van Dijke, M., Schouten, B., Bardes, M. (2009). When does self-sacrificial leadership motivate prosocial behavior? It depends on followers’ prevention focus. Journal of Applied Psychology, Vol 94(4), Jul 2009, 887-899. doi: 10.1037/a0014782

[6] Dictionary.com. (2013). Altruism. Retrieved, September 26, 2013, from, http://dictionary.reference.com/browse/altruism

[7] Eisenberg, N., Guthrie, I., Cumberland, A., & Murphy, B. (2002). Prosocial development in early adulthood: A longitudinal study. Journal of personality and Social Psychology, 82(6). 993-1006.

[8] Eisenberg, N., & Miller, P. (1987). Empathy, sympathy, and altruism: empieical and conceptual links. In N. Eisenberg & J. Strayer (Eds.), Empathy and its development (pp. 292 – 316). Cambridge: Cambridge University Press.

[9] Harquail, C. (1996). When on speaks for man: the influence of social identification on group advocacy in organizations. Unpublished PhD dissertation University of Michigan, Ann Arbor, MI.

[10] Kohn, A. (1990). The Brighter Side of Human Nature: altruism and empathy in everyday life. N.Y.: BasicBooks.

[11] Lorenzi, P. (2004). Managing for the common good: Prosocial leadership. Organizational Dynamics, 33(3), 282-291. doi:10.1016/j.orgdyn.2004.06.005

[12] Meyerson, D., & Scully, M. (1995). Tempered Radicalism and the Politics of Ambivalence and Change. Organization Science, 6(5), 586- 600.

[13] Oliner, S., & Oliner, P. (1988). The Altruistic Personality. N.Y.: The Free Press.

[14] Spacapan, S., & Oskam, S. (Eds.). (1992). Helping and Being Helped. Newbury Park: Sage.

[15] Wills, T.A. (1992). The Helping Process in the Context of Personal Relationships. In S. Spacapan & S. Oskamp (Eds.). Helping and Being Helped: Naturalistic Studies. Newbury Park: Sage.

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WALMART CAN SOLVE THE INEQUALITY PROBLEM. Authors:

KINSLEY, MICHAEL Source:

New Republic. 10/21/2013, Vol. 244 Issue 17, p12-14. 3p. Document Type:

Article Subjects:

WORKING poor -- United States MINIMUM wage -- United States WAL-Mart Stores Inc. WAGES -- United States INCOME distribution -- United States POVERTY reduction

Abstract: The article looks at income inequality in the U.S. as of 2013, focusing on the working poor and on retail company Wal-Mart. The author notes the U.S. minimum wage increase that would be needed so that a person working full-time would be above the poverty level. He proposes that Wal-Mart agree to such a wage increase and pass the cost along to its customers, saying it would represent a minor cost increase to the average customer.

Lexile: 1000

Full Text Word Count: 1519

ISSN: 0028-6583

Accession Number: 90544944

Database: MAS Ultra - School Edition

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ESTHER BREGER ASSISTANT EDITOR AT THE NEW REPUBLIC

PLUS, TWO OTHER COMPELLING DETAILS FROM MY LAST FEW WEEKS OF READING.

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OF TOO REAL REALITY TV AND AMISH JOURNOS

A new three-episode Bravo reality series, “The People’s Couch,” consists of regular Joes in their houses watching and commenting on television from the previous week. — DEADLINE

NASA is looking for volunteers to lie in bed for several days.

Participants will be paid $18,000. — FORBES

ACCORDING TO A STUDY, FOOTBALL FANS’ SATURATED-FAT INTAKE INCREASES AS MUCH AS 28 PERCENT IN THE 24 HOURS AFTER THEIR TEAM LOSES AND DECREASES SIGNIFICANTLY AFTER VICTORIES. THE EFFECT WAS MOST PRONOUNCED ON MONDAYS, AND SHARPER IN CITIES WITH BELOVED TEAMS. (NUMBER ONE WAS FREQUENTLY PITTSBURGH.) — THE NEW YORK TIMES

WALMART CAN SOLVE THE INEQUALITY PROBLEM AND IT’LL ONLY COST YOU $12.50 A YEAR. B Y M I C H A E L K I N S L E Y

T HE PROBLEM OF INCOME inequality in the United States is really three different problems.

One is the concentration of income and wealth at the very top—the notorious 1 percent making more than about $250,000 a year. A second problem is the stagnating incomes of the middle class, in particular the lower–middle class: those with family income of about $32,000 to $50,000 a year. The third problem is poverty: the 15 percent of Americans—or about 46 million people—earning less than the poverty line of about $23,500 a year, which is the government’s estimate of the minimum amount needed to feed, clothe, and house a family of four.

In terms of importance, it seems to me, the problem of poverty comes first. When people actually don’t have enough to eat,

Which leads to the second reason why skeptics about enhanced government involvement in the network might be wrong. The public mistrusts the NSA not just because of what it does, but also because of its extraordinary secrecy. To obtain the credibility it needs to secure permission from the American people to protect our networks, the NSA and the intelligence community must fundamentally recalibrate their attitude toward disclosure and scrutiny. There are signs that this is happening—and that, despite the undoubted damage he inflicted on our national security in other respects, we have Edward Snowden to thank.

“Before the unauthorized disclosures, we were always conservative about discussing specifics of our collection programs, based on the truism that the more adversaries know about what we’re doing, the more they can avoid our surveillance,” testified Director of National Intelligence James Clapper last month. “But the disclosures, for better or worse, have lowered the threshold for discussing these matters in public.”

In the last few weeks, the NSA has done the unthinkable in releasing dozens of documents that implicitly confirm general elements of its

collection capabilities. These revelations are bewildering to most people in the intelligence community and no doubt hurt some elements of collection. But they are justified by the countervailing need for public debate about, and public confidence in, NSA activities that had run ahead of what the public expected. And they suggest that secrecy about collection capacities is one value, but not the only or even the most important one. They also show that not all revelations of NSA capabilities are equally harmful. Disclosure that it sweeps up metadata is less damaging to its mission than disclosure of the fine-grained details about how it collects and analyzes that metadata.

It is unclear whether the government’s new attitude toward secrecy is merely a somewhat panicked reaction to Snowden, or if it’s also part of a larger rethinking about the need for greater tactical openness to secure strategic political legitimacy. Let us hope, for the sake of our cybersecurity, that it is the latter. ○

Jack Goldsmith, a contributing editor, teaches at Harvard Law School and is a member of the Hoover Institution Task Force on National Security and Law.

1 percent in ways that don’t add to general prosperity. And if they don’t add enough to general prosperity to cover the amount they take away from it, then their share is coming out of everybody else’s.

Solving the problems of the poor and middle class will require a substantial contribution from the affluent—not just the top 1 percent, or even the top 10 percent, but the top 15 or 20 percent. But there’s no need to be vindictive about it. Affluent people should fork out a bit because they’ve been lucky, not because they’ve been evil. It only takes $50,000 a year or so to put you in the top half of income distribution in this country, so the upper–middle class can expect any serious readjustment of income distribution to cost them initially rather than benefit them.

The federal minimum wage is $7.25 an hour. (In some states, and the District of Columbia, it’s a bit higher.) For a 40-hour week, 50 weeks a year, that’s $14,500, which is just over three-fifths of the minimum amount the government says you need to survive.

Besides being brutally unfair, this is illogical. Shouldn’t people who are working full-time earn enough to live at least at the poverty line? They’re working as hard as they can. What else can they do? The entire language of the old debate about the War on Poverty is outmoded. These are not, for the most part, “welfare queens” driving their Cadillacs to the welfare office to collect large checks, which they use to buy drugs and liquor for their boyfriends. These are hard-working people, doing everything that we as a society ask of them. Surely we can afford to say: If you work a full-time job, you may be hard-up, but you won’t be poor.

The most straightforward way to make sure that every job pays at least poverty- level wages would be to simply require it. The current minimum wage doesn’t quite do that. A minimum wage of $12.50 an hour would be $25,000 a year—just a hair above the poverty line.

Employers would scream, this will destroy jobs. In fact, they are already screaming in Washington, where the city council passed a “living-wage” law requiring big-box stores to pay their employees at least $12.50 an hour. The bill was aimed at Walmart, which is planning to open six stores in and around Washington. Walmart made clear that three of the stores, and possibly all six, would not be built if the living-wage law

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you’ve got an emergency on your hands. Next comes the middle class, where no one is starving, but the American promise of steady improvement (the expectation that your children will live better than you did) is being betrayed.

Not trivial but least important is the problem of the rich getting richer. Many would say that’s hardly a problem. That it’s an achievement. And in some cases that’s true: Some people get rich in ways that add more to general prosperity than they take out. But others climb into the

were enacted. The mayor, Vincent Gray, vetoed the bill on the grounds that it was unfair to discriminate against one type of store, and because it would cost jobs. The council failed to override the veto.

It seems beyond dispute that raising the minimum wage will cost jobs. Except in rare circumstances, when the price of something (in this case, labor) goes up, demand for it goes down. There was a school of thought that sometimes raising the price of labor actually increases employment. This is hard to believe. But you don’t need to believe it in order to favor a higher minimum wage.

The minimum wage costs jobs. It makes our economy less efficient. Opponents of raising the minimum wage act as if this is the end of the story. But it isn’t. Many government policies reduce economic efficiency and make our society a bit poorer than it otherwise would be. But we’ve made a decision that other social goals make it worth the cost. So it is with the minimum wage.

The minimum wage has been around since the New Deal. If it’s so clear that raising it costs jobs, why do we not hear more poor people complaining about it? (I’ve never heard any poor person complain that the minimum wage is too high.) The reason? For a low-income individual, the minimum wage is a gamble. You might lose your job. But you might get a raise. The average wage of a Walmart “associate” is $8.81 an hour. A raise to $12.50 would be 41 percent. If you make only the federal minimum wage of $7.25 (as many Walmart associates do, though the exact number is subject to dispute), your raise to a “living wage” would be 72 percent! That is a deal worth considering.

Trouble is, Walmart is not offering that deal. Walmart sells as cheaply as it can, and that requires hiring people as cheaply as it can. Forcing Walmart to pay higher wages than its competitors is unfair, and forcing it to pay people more than it has to is unfair to its customers, many of them poor themselves, who would have to pay higher prices.

A confession: I love shopping at Walmart. In fact, I love just wandering around Walmart, admiring the cornucopia of stuff for sale and the miraculously low prices. I can hardly wait for six new Walmarts in the Washington area. (Right now there are none except in distant suburbs.)

However, I don’t want to exploit my fellow Americans by underpaying them. I would happily pay a bit more for the knowledge that nobody involved in the

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The Budget, the most popular Amish newspaper,

doesn’t run crime stories and cuts out mentions of elderly women who live alone lest it put them in danger. One thing

it has in common with more modern media companies?

Contributors are unpaid. — THE WALL STREET JOURNAL

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14 making and selling of whatever I purchase has been paid less than $12.50 an hour. How much is “a bit”? According to a study two years ago by scholars at the University of California at Berkley and City University of New York, the average Walmart customer spends about $1,200 a year there. (Good news for me: I am below average—but I can rectify that!) Even if the entire cost of a wage increase (to $12, not $12.50) were passed on to customers, the cost to an average customer would be just more than 1 percent, or $12.50 a year.

Who wouldn’t pay 12 bucks and change for the right to roam the Walmart aisles without guilt? Well poor people might not be able to. But, depending on how it’s done, they may not have to.

There’s no need to force Walmart into raising its wages and prices. Let the market work! These days almost everything you buy carries a label making the claim that in some way it is morally superior. It is “organic.” It is “gluten free.” It is “cruelty free”—cruelty to animals, that is. Everything from dishwasher detergent to entire office buildings gets certified by how “green” it is.

Why not create a label symbol indicating that the product you are about to buy is “poverty-free”—i.e., no American involved in making it or getting it to you makes less than $12.50 an hour?

Obviously, this should not be limited to Walmart, but Walmart could lead the way. On some items, they might want to try putting poverty-free and non-poverty- free items side by side on the shelf and see how many people go for each.

Yes, yes, I know there are problems. Imports, for one. A reason for Walmart’s low prices is that much of the labor that goes into its products is that of foreigners in distant lands who are lucky to get 12 cents an hour, let alone $12. Furthermore, that’s a good thing, the bottom rung on the ladder to the middle class.

As long as it’s voluntary, the extra cost of a living wage can be passed along to the customers, and any competitive disadvantage should disappear. Or here’s an idea: Hidden cameras could photograph the greedheads who wouldn’t pay 11 cents more for poverty- free peanut butter and bought the cheaper stuff instead. Their pictures could be posted at checkout.

No? Well, maybe that goes too far. ○

Michael Kinsley is editor-at-large of THE NEW REPUBLIC.

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e.g., “Bro, you’re gonna rock your presentation. Initiate beast mode!”

Illustration by Icinori

WHO USES IT: IVY LEAGUE B-SCHOOL STUDENTS GETTING IN THE ZONE / GYM RATS / SEATTLE SEAHAWKS

RUNNING BACK MARSHAWN LYNCH

WHEN YOU’RE A YOUNG CAPITALIST ON THE MAKE, YOU DON’T MERELY prepare for high-pressure meetings. You go into “beast mode.”

That’s the word that Harvard Business School–types have designated for the aggressive headspace they enter before important tête-à-têtes and job interviews. A young project manager turning down after-hours beers, for instance, may explain that he has to pull an all-nighter, e-mailing, “ACTIVATE EXCEL BEAST MODE.”

The term originates with Sega’s Altered Beast, a video game starring a Roman centurion who could morph into mythical creatures. Its doltish brand of masculinity (the centurion must rescue Athena—you know, the Greek goddess of war?) made the leap to the football world in 2007 when Marshawn Lynch, then a Berkeley undergraduate, told an inter- viewer he was in “beast mode” when he was on the field. The phrase became Lynch’s nickname and is now employed by jocks everywhere. Today, Twitter is lousy with people getting into #beastmode ahead of their gym routines.

Wall Street likes its slang to be dudely. There was, says the anthropolo- gist Grant McCracken, “a particularly annoying period when people kept asking (or saying) that something ‘hunted.’ As in, ‘I think that new idea really hunts.’ ” The late Nora Ephron remembered a time when business- men broadcasted their machismo by speaking, it seemed, only in God- father quotes. McCracken observes that Wall Street lingo has typically sounded “muscular, capable, decisive, and in-the-know,” and not nearly as frenzied as “beast mode.” But today’s MBAs were reared on video games and are entering a Wall Street that recently tanked the global economy and has become the frenetic domain of quants that buy and drop stocks in a fraction of a second. Who could survive the melee that is modern finance, save for someone with the improbable strength of a video-game action hero? – MOLLY REDDEN

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Primate Sociality to Human Cooperation. Authors:

Hawkes, Kristen1 [email protected] Source:

Human Nature. Mar2014, Vol. 25 Issue 1, p28-48. 21p. Document Type:

Article Subject Terms:

*DEVELOPMENTAL psychology *INTERPERSONAL relations *APES *LIFE history *CHILD caregivers *PARENTAL behavior in animals

Author-Supplied Keywords: Genus Pan Grandmothers Human evolution Infant development Life history

Abstract: Developmental psychologists identify propensities for social engagement in human infants that are less evident in other apes; Sarah Hrdy links these social propensities to novel features of human childrearing. Unlike other ape mothers, humans can bear a new baby before the previous child is independent because they have help. This help alters maternal trade-offs and so imposes new selection pressures on infants and young children to actively engage their caretakers' attention and commitment. Such distinctive childrearing is part of our grandmothering life history. While consequences for other cooperative activities must surely follow, the novel rearing environments set up by helpful grandmothering can explain why natural selection escalated preferences and motivations for interactivity in our lineage in the first place, and why, unlike other aspects of infant development, social sensitivities are not delayed in humans compared with genus Pan. [ABSTRACT FROM AUTHOR]

Copyright of Human Nature is the property of Springer Science & Business Media B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Author Affiliations: 1Department of Anthropology, University of Utah, 270 S 1400 E room 102 Salt Lake City 84112 USA

ISSN: 1045-6767

DOI: 10.1007/s12110-013-9184-x

Accession Number: 94871212

Primate Sociality to Human Cooperation Why Us and Not Them?

Kristen Hawkes

Published online: 4 December 2013 # Springer Science+Business Media New York 2013

Abstract Developmental psychologists identify propensities for social engagement in human infants that are less evident in other apes; Sarah Hrdy links these social propensities to novel features of human childrearing. Unlike other ape mothers, humans can bear a new baby before the previous child is independent because they have help. This help alters maternal trade-offs and so imposes new selection pressures on infants and young children to actively engage their caretakers’ attention and commitment. Such distinctive childrearing is part of our grandmothering life history. While conse- quences for other cooperative activities must surely follow, the novel rearing environ- ments set up by helpful grandmothering can explain why natural selection escalated preferences and motivations for interactivity in our lineage in the first place, and why, unlike other aspects of infant development, social sensitivities are not delayed in humans compared with genus Pan.

Keywords Human evolution . Life history. Genus Pan . Grandmothers . Infant development

In the past decade or so, prosocial emotions and cooperative capacities have become a major focus of researchers seeking to identify primary distinctions between humans and other primates (Cartmill 2010). Yet an increasing wealth of evidence shows social relationships to be major concerns of other primates as well (e.g., Aureli and de Waal 2000; Cheney 2011; Cheney and Seyfarth 2007; de Waal 2000, 2011; Dunbar 2010; Dunbar and Shultz 2007; Kappeler and van Schaik 2007; Seyfarth and Cheney 2007, 2012). Many social abilities once seen as uniquely human have been documented among our near relatives (e.g., Bard 2012; Call and Tomasello 2008; de Waal 2012; Hare and Tan 2012; Rosati et al. 2010). We belong to an order of remarkably gregarious and socially sensitive animals.

Hum Nat (2014) 25:28–48 DOI 10.1007/s12110-013-9184-x

K. Hawkes (*) Department of Anthropology, University of Utah, 270 S 1400 E room 102, Salt Lake City, UT 84112, USA e-mail: [email protected]

Most assume that features shared with our cousins were the phenotypic foundation for directional selection (Fisher 1958; West-Eberhard 2003) that eventually led to the eco- nomic interdependencies and elaborate social constructions that now set living humans apart (Kappeler and Silk 2010). But contemporary differences in social accomplishments and our modern capacities and tendencies required step-by-step changes. All we see now was not present at the initial divergence of our genus. What was? Here I follow Sarah Hrdy’s (1999, 2009, 2013) hypothesis that our distinctive motivations for cooperation and mutual understanding initially evolved in a socially sophisticated ancestor as a conse- quence of selection on mothers and infants in novel childrearing environments.

Hrdy builds on Michael Tomasello and colleagues’ findings that shared intention- ality distinguishes humans from other apes (Call 2009; Tomasello 2008; Tomasello and Carpenter 2007; Tomasello and Herrmann 2010; Tomasello et al. 2005). The evolu- tionary benefit they identify for this capacity is the widespread cooperation that it enables, the Cultural Intelligence Hypothesis (Herrmann et al. 2007). But as Hrdy notes, those benefits do not explain why shared intentionality evolved in our lineage and not in other genera of the hominid radiation. In contrast, the selection pressures that accompanied the shift away from independent mothering to our distinctive childrearing might explain why shared intentionality evolved in our lineage in the first place. Immediate survival advantages could have selected infants more effective at engaging care- givers long before the evolution of more elaborate cultural interdependencies—establishing the social preferences that are then their foundation.

If selection on infants in novel rearing environments accounts for the initial evolu- tion of distinctively human prosociality, what accounts for the origins of those rearing environments? As known ethnographically, human mothers and dependent children get help from many sources (Howell 2010; Hrdy 1999, 2009; Sear and Mace 2008). Older siblings contribute (e.g., Kramer 2011; Kramer and Ellison 2010), and the fact that humans form pair bonds and the fathers sometimes help has an especially venerable place in ideas about the evolution of our lineage (e.g., Hill and Hurtado 2009; Kaplan et al. 2000, 2010; Lancaster and Lancaster 1983; Lovejoy 1981; Washburn and Lancaster 1968). Men’s work contributes substantially to what mothers and children consume, but men often spend time and energy supplying collective goods rather than directly provisioning their mates and offspring (Hawkes 1990, 1993a, b, 2004; Hawkes and Bliege Bird 2002; Hawkes et al. 1991, 2001, 2010). What and how much men do as husbands and fathers varies widely both within and between ethnographic commu- nities (Gray and Anderson 2010; Hawkes et al. 2001; Hrdy 1999, 2008; Marlowe 2003). Neither facultative fathering nor male ontogeny and sexual dimorphism (Bribiescas 2006; Puts 2010:161–163 and references therein) are consistent with an evolutionary history of obligate paternal care.

The argument I pursue here is that the distinctive dependence of human mothers on rearing help initially evolved with grandmothering. Proposed to account for the increased longevity, delayed maturity, and early weaning of humans compared with our closest living relatives (Hawkes 2003; Hawkes et al. 1997, 1998; O’Connell et al. 1999), helpful grandmothering allows human mothers, unlike other ape mothers, to have next babies before the previous ones are independent. Grandmothering sets up the novel selection pressures on mothers and infants identified by Hrdy. Those pressures make social engagement advantageous to infants, so natural selection favors early social development despite delays in other aspects of life history.

Hum Nat (2014) 25:28–48 29

This notion of early social development in human infants may seem mere fantasy in light of still-influential views such as those of Montague (1961) about the first year of human life. He said, “the human infant is quite as immature at birth as is the little marsupial immaturely born into its mother’s pouch, there to undergo its exterogestation until it is sufficiently matured” (161:157). But comparisons between humans and chimpanzees contradict claims of unique helplessness in human babies (Matsuzawa 2012; Schultz 1969).

The hypothesis that social capacities are shaped by selection on infants as a result of novel rearing environments makes the developmental timing of social cognition and emotions a crucial line of evidence about our evolution. Brian Hare (2011) and colleagues (Wobber et al. 2010) recently highlighted the evolutionary importance of timing shifts in the cognitive ontogeny of humans and genus Pan. My argument shares their assumption that foundational abilities for human sociality must have been present in our last common ancestor with the other great apes. However Hare and collaborators cite the Cultural Intelligence Hypothesis to explain the evolution of human social cognition: benefits are “participating and exchanging knowledge in cultural groups” (Herrmann et al. 2007:1360). Since natural selection is blind to future consequences, what evolved later cannot explain initial selection for our distinctive prosociality, but selection exerted by rearing environments might. If elevated social sensi- tivities evolved in humans because they gave survival advantages in infancy, social skills and emotions should develop earlier in humans than in genus Pan.

After summarizing Tomasello and colleagues’ findings about shared intentionality, Hrdy’s arguments about the novel selection pressures of human rearing environments, and the hypothesized role of grandmothering in the evolution of human life history, I consider some comparative evidence about the developmental timing of social abilities in humans and genus Pan. The evidence, though varied, disputed, and incomplete, shows human babies to be socially engaging and discriminating—perhaps right from birth. Although this early development could have come after cultural propensities that evolved in our lineage for other reasons, a simpler alternative reverses the causal arrow. That reversal makes the evolution of our distinctive prosociality an aspect of our grandmothering life history, which laid the foundation for the subsequent evolution of language, vastly expanded the range of venues for male status competition (Coxworth 2013), and escalated the social and economic interdependence of our cultural lives.

Tomasello and Colleagues’ “Shared Intentionality”

Tomasello’s observations and experiments in the 1980s identified differences in social cognition between children and chimpanzees. Subsequent work continued to build evidence for and improve characterization of those differences. Recently Tomasello and Call (2010:249) said:

the totality of current evidence strongly suggests that . . . the fundamentals are the same for chimpanzees and humans: a perception-goal psychology enabling the understanding of important aspects of intentional, rational action and perception. . . . Most of human cognitive uniqueness derives . . . from some species-unique social-cognitive skills and motivations for sharing intentional states with others in special types of cooperative and communicative activities.

30 Hum Nat (2014) 25:28–48

Tomasello (e.g., 1999) has also written at length and persuasively about the funda- mental role of shared intentionality in human life. It is “what is necessary for engaging in uniquely human forms of collaborative activity in which the plural subject ‘we’ is involved: joint goals, joint intentions, mutual knowledge, shared beliefs—all in the context of various cooperative motives” (Tomasello 2008:6–7).

The arguments and ever-growing evidence for this human distinction and about its consequences for human language, social learning, cultural transmission, and cooper- ation are persuasive. Less so are the answers as to why these capacities and motivations evolved in humans and not in other apes. As Hrdy (2009) asks, “Why us and not them?” Tomasello (2009:75, and further elaborated in Tomasello et al. 2012) pins the shift on cooperation in foraging activities. Hrdy’s analysis of the cooperative childcare that distinguishes humans from the other great apes is noted as one possibility to explain why we seem to be “more socially tolerant and less competitive over food” (2009:84). But selection on infants as a consequence of novel rearing environments is mentioned only in passing. Here I assemble reasons to make it central.

Hrdy’s Analysis of Rearing Environments

In Mother Nature (1999:177ff) Hrdy drew attention to contrasts between the “discrim- inating solicitude of human mothers” and the nearly “unconditional devotion charac- teristic of mother monkeys and apes.” She noted that because humans bear the next baby before the previous one reaches independence, they cannot focus unconditionally on their new infant. A mother’s reproductive success will depend on how she distrib- utes attention among multiple dependents. This predicament inevitably puts selection pressures on her capacities and motivations to calibrate costs and benefits and shift investment accordingly. Moreover, the ability to rear overlapping dependents can only evolve if help is usually available. This implies selection on mothers both for situation- dependent commitment and for capacities to juggle the additional tasks of recruiting and maintaining helpers.

Hrdy took initial steps in 1999 toward exploring the consequences of these shifts in maternal strategies for selection on the social abilities of infants and children. In subsequent papers, and especially in Mothers and Others (2009), she highlighted those important effects, not only canvassing findings in developmental psychology but also making explicit links to Tomasello’s arguments about shared intentionality.

Drawing widely on both ethnography and primatology, Hrdy documented contrasts between the problems faced by human and other ape infants. Whereas other ape infants are inseparable from their mothers, each having its mother’s undivided attention, human babies often spend substantial amounts of time away from their mothers right from birth. The combination of mothers’ distributed concerns and the importance of other helpers puts a premium on the capacities of infants themselves to engage both mothers and others (Chisholm 2003).

The “why us and not them?” question has not been Tomasello’s central concern. In contrast, Hrdy has focused on the very particular adaptive advantages conferred on human infants and youngsters who are better at engaging their mothers and other potential caretakers (Chisholm 2003). Payoffs for slight improvements in attracting commitment will be greatest, and selection strongest, where that commitment is most

Hum Nat (2014) 25:28–48 31

crucial. In humans as in other primates, mortality is highest in infancy. That is when caretakers’ attentions are a matter of life or death.

Grandmothering and Human Rearing Environments

The Grandmother Hypothesis (Hawkes 2003; Hawkes et al. 1997, 1998; Kim et al. 2012; O’Connell et al. 1999) addresses the evolution of human rearing environments. It proposes that ancestral populations faced ecological changes in the Plio-Pleistocene that restricted the availability of the foods just-weaned juveniles could handle for themselves. Mothers who did not follow the retreating forests had to provision their weanlings, and this longer period of juvenile dependence presented a novel opportunity for any older females still surviving as their fertility was ending. They could enhance their own fitness by helping provision their dependent grandchildren and allowing daughters to have their next babies sooner without reductions in previous offspring survival. As a consequence, our lineage evolved greater longevity, later maturity, and earlier weaning from an ancestral life history that was like that of the other living great apes, all without altering the age at which female fertility ends.

The hypothesis was initially stimulated by observations of high levels of economic productivity by women past childbearing among East African Hadza hunter-gatherers (Hawkes et al. 1989, 1997), but grandmother effects have been looked for and usually found in an array of human populations (e.g., Lahdenperä et al. 2004; Sear and Coall 2011; Sear and Mace 2008; Voland et al. 2005). Formal modeling has shown that when resources produced by the older generation are important to reproductive success, it is production and not fertility that determines selection against senescence, so humanlike productivity can maintain humanlike aging rates (Lee 2003, 2008).

A mathematical simulation (Kim et al. 2012) now shows that grandmothering alone can evolve an apelike life history into a humanlike one. Verbal arguments about the ancestral shift in life history (Hawkes 2003; Hawkes et al. 1997, 1998) assumed that regularities observed among life history traits across the living primates held in the past as well: greater adult longevity favored later maturity and later ages at independence (Charnov 1993; Charnov and Berrigan 1993; see Hawkes 2006a for review). Peter Kim’s mathematical model (Kim et al. 2012) assumes that too. The simulation begins with a population at an apelike equilibrium for longevity, age at maturity, and age at independence. The addition of helpful grandmothering favors greater longevity in both sexes and shifts that equilibrium. Apelike longevity evolves into the human range, with increased age at first birth and lengthened duration of juvenile dependence. When adult lifespans are apelike, very few can be helpful grandmothers—less than 1% of the caregivers in this simulation. Nevertheless, those few are enough for helpful grandmothering to drive the evolution of increased longevity and expand the fraction of grandmothers into the human range. That happens because longer-lived grand- mothers can help more descendants, and their help gives greater benefits to longer- lived mothers.

The model makes no assumptions about shifts in caretaker preferences. Hrdy has described notable “donative intent” in elder female monkeys (1999, and see Wroblewski 2008 for chimpanzees). This, plus widespread “baby lust” in primates, suggests that attraction to infants has deep phylogenetic roots with maternal

32 Hum Nat (2014) 25:28–48

protectiveness the main impediment to infant sharing (Hrdy 2009). Mothers might most trust their own mothers with access to dependents, and grandmother effects would have the largest fitness impact through help to daughters’ offspring because assurance of shared genes through sons is uncertain. But initial critiques of the Grandmother Hypothesis cited female natal dispersal throughout our lineage that would have kept mothers and adult daughters apart. Now evidence is plentiful that hunter-gatherers do not show the presumed patrilocal bias (Alvarez 2004; Hill et al. 2011; Marlowe 2004; Wilkins and Marlowe 2006). Nevertheless Peter Kim’s mathematical model (Kim et al. 2012) is deliberately conservative, allowing grandmothers to help any dependent juvenile, not just daughters’ children.

The model is, of course, an extreme simplification, aimed to see whether (very weak) helpful grandmothering could propel the evolution of a humanlike life history from an apelike one. It does not include the maternal problem of distributing attention among newborns and older dependent juveniles because model mothers can only start a new pregnancy when not caring for a dependent. Model juveniles do not vary in how likely they are to receive care, except that grandmothers take older dependents first and cannot take them before they reach age two. Caretakers—both mothers and grandmothers—are only allowed to care for one dependent at a time. All these constraints obviate the distributed attention problem for model mothers. But there are never enough grandmothers in the model to take on all the juveniles eligible for non- maternal help. If juveniles varied in their ability to engage that help, the mothers of those better able to do so would have shorter birth intervals and higher reproductive success. Even without considering differential allocation of maternal investment, a rearing environment with helpful grandmothers has ample room for selection on youngsters’ social abilities.

Cognitive Ontogeny

On these grounds, grandmothering would have consequences for the ontogeny of social cognition. More than 30 years ago, in Ontogeny and Phylogeny, Stephen J. Gould was especially interested in “the immediate significance of acceleration and retardation in the evolution of life-history strategies for ecological adaptation” (1977:8). He noted especially the long childhoods and delayed maturation of our own species. Although Gould recognized there must be diversity in patterns of development, he concluded that “Neoteny has been a (probably the) major determinant of human evolution” (1977:57).

Aspects of human life history are unassailably slow relative to those of other great apes. Adult lifespans are longer, the beginning of adulthood is later, and juveniles are dependent longer. But weaning age is earlier, and subsequent work has mostly falsified global neoteny for growth and development (e.g., Godfrey and Sutherland 1996; Leigh and Park 1998; McKinney and McNamara 1991; Minugh-Purvis and McNamara 2002; Parker et al. 2000; Shea 1989; Thompson et al. 2003, see Hawkes 2006b for review). Still, developmental timing shifts remain likely mechanisms for the evolution of differences. Gould (1977) cited King and Wilson’s (1975) demonstration that the genetic differences between humans and chimpanzees are small compared with the many organismal differences between the two species. He endorsed their hypothesis that the phenotypic differences must be largely due to regulatory mutations.

Hum Nat (2014) 25:28–48 33

“Heterochronic changes are regulatory changes; they require only an alteration in the timing of features already present” (Gould 1977:9).

Gene Expression and Brain Imaging

Gene expression studies now reveal regulatory changes making the neoteny hypothesis again a useful guide to research. Somel et al. (2009) studied gene expression in postmortem brain tissue from rhesus macaques, chimpanzees, and humans. They found slightly more than 3,000 genes expressed in all three species. Using rhesus as an out group they could assign about 10% to four developmental categories based on whether there were timing changes in humans or chimpanzees and whether the changes were delay or acceleration. Of these, 38% showed timing changes in humans that were delayed relative to chimpanzees, about twice as many as they found in any of the other three categories. While the phenotypic consequences of the genes expressed are unknown, correlations between age of expression and observed differences in devel- opment at those ages are suggestive. They reported that “at least in one of the two cortical regions studied, the neotenic shift is most pronounced at the time when humans approach sexual maturity, a process known to be delayed in humans relative to chimpanzees or other primates” (2009:5746).

Somel et al. (2012) noted an array of hypotheses to link delayed maturity in humans to our notable longevity. Here I privilege the Grandmother Hypothesis to explain it. As noted, the addition of Hrdy’s arguments about rearing environments also connects grandmothering to selection for accelerated development in infant social cognition. That connection implies early expression in genes associated with social sensitivities. Even though the phenotypic effects of the genes in Somel and colleagues’ gene expression study remain unknown, their results could provide an initial test of whether any genes show accelerated expression in human babies’ brains compared with brains of baby chimpanzees.

Approximately 22% of the genes with expression changes in Somel et al. (2009) do show acceleration in human brains, but the authors do not report the ages at which acceleration is most prominent. What they do say is not encouraging for the expectation of early social acceleration: “human-chimpanzee expression divergence is relatively small after birth” (2009:4746). But perhaps a focus especially on the first few years would show different results. That possibility is suggested by a report from Sakai and colleagues (2011), who used brain imaging to compare the development of white matter (WM) between chimpanzee and human infants and found “the rate of prefrontal WM volume increase during infancy was slower in chimpanzees than in humans” (2011:1397). Their conclusion, consistent with the expectations developed here, is that “the lineage leading to modern humans has undergone substantial evolutionary modifications, resulting in the rapid development of the prefrontal connections during infancy. This likely facilitates the development of complex social interactions” (2011:1401).

Behavior in the Wild

Frans Plooij (1984) studied six chimpanzee mother-infant pairs at Gombe, noting that mothers were alone (with their infants) most of the time, with infants on their mother’s body for the first 3 months. By 8 months infants spent 80–90% of their time in physical

34 Hum Nat (2014) 25:28–48

contact with their mothers, and still the majority of their time by 12 months (1984:97). Initially mothers paid little visual attention to their babies. Until about 9 months the baby would grasp the mother’s food and initially she allowed this. “Soon, however she passively prevented the baby from taking the food by not letting go of it or by withdrawing her hand from its advance. In such cases the baby (or young infant) kept trying to obtain the food directly, without even looking up into the mother’s face” (1984:116).

Contrast that description with Melvin Konner’s account (1972:292–293) of human infant development among Ju/’hoan hunter-gatherers:

From their position on the mother’s hip . . ., the infant’s face is just at the eye- level of desperately maternal 10-to-12-year-old girls who frequently approach and initiate brief, intense, face-to-face interactions, including mutual smiling and vocalization. . . . [Infants] are passed from hand to hand around the fire for similar interactions with one adult or child after another. . . . Objects are often used to distract fretting babies. They become regular targets for the phrase “look at that” by the second week. . . . Crying, the pucker face, and sub-cry vocalizations are the infant’s most powerful survival weapons. They appear on the first day of life and remain prominent items in the behaviour repertoire throughout early childhood.

Konner reports that an infant “is born with the basis of social behavior. . . . By smiling he can make [his mother and others] smile and vocalize, or even make his surroundings explode with human sounds. By dint of these powers he is a social animal at birth” (1972:294).

These accounts suggest more interactivity, earlier, in human than in chimpanzee infants. But Plooij noticed “aversive reactions” to strangers at 6 months in his chim- panzees whereas Konner’s summary in his recent broad synthesis of The Evolution of Childhood (2010:229) suggests it may be slightly later in human infants. Across a wide range of cultural and socioeconomic contexts, “the growth of social fears with the concomitant growth of attachment appears to be a universal feature of the second half year.”

Observations and Experiments with Captive Chimpanzees

Results from measurements on captive chimpanzees indicate notable similarities to humans in both attachment and its developmental timing. van IJzendoorn et al. (2009) evaluated the attachment behavior of 12-month-old chimpanzees using the Strange Situation Procedure (SSP) designed to reveal the quality of attachment in human infants. In the SSP infants are placed an unfamiliar environment and confronted by a stranger with two brief separations from their caregiver. The researchers found that “Expert coders trained on hundreds of human infant attachment SSP’s were readily able to independently identify individual attachment patterns in chimpanzee infants with a high level of inter-coder reliability” (2009:180). They concluded that “the attachments of infant chimpanzees appear surprisingly similar to those of human infants” (2009:181).

Van IJzendorn and colleagues (2009) also reported results from the Bayley Scales for Infant Development (Bayley 1969) on captive chimpanzee infants and compared them with results from human infants. The Bayley scales are used to assess the

Hum Nat (2014) 25:28–48 35

development of motor, language, and cognitive skills in human infants. Chimpanzee scores at 3.5 months were higher than the human standard (Bard and Gardener 1996) and then declined with age relative to human norms, overlapping them at about 9 months. Investigators found that “In comparison with normed human US samples, 9-month-old nursery-reared chimpanzees would be considered to show typical cogni- tive development, apart from the lack of language skills” (van IJzendoorn et al. 2009:181). But, “by 12 months, the chimpanzees were not combining objects or using objects in functional ways, including tools . . ., [whereas] at 10–12 months, human infants began to exhibit turn-taking, tool use, and other object-object combinations” (Bard and Gardener 1996:240–241).

Another standard measure of social abilities that has been applied to both human infants and captive nonhumans is Gallup’s (1970) Mark and Mirror Test. The test is whether subjects recognize the surreptitiously marked reflection in the mirror as themselves. Lewis and colleagues (1989) found that the development of self- recognition in human infants at about a year and a half indicates a “social self” with the capacity to experience self-conscious emotions such as embarrassment, pride, empathy, and jealousy. Chimpanzee infants pass this test after the age of two (Lin et al. 1992; see Bard et al. 2006 for more nuanced discussion of protocols with more subjects).

Kim Bard and colleagues (2011) used the Brazelton Neonatal Behavioral Assessment Scale (NBAS) to compare newborn development between humans and chimpanzees and to investigate differences among chimpanzees by captive care re- gimes. The NBAS was developed by Brazelton (1984) to evaluate infant adjustment to life outside the womb. Of the 21 items and four cluster scores, Bard et al. (2011:48) found the “human group was distinct in only 1 of the 25 NBAS scores (the human group had significantly less muscle tone than all the chimpanzee groups).”

Care Regimes and Standards of Comparison

Infant developmental norms and studies of human infants have largely relied on Western middle-class babies. Captive chimpanzee subjects (both babies and adults) have usually been tended as infants by humans in nurseries (Bard 2012). Neither subject pool is representative (e.g., Henrich et al. 2010; Leavens et al. 2010). Apparent differences may be inflated because the human babies tested have had early experiences that—unlike in some (but not all) cultural settings (Lancy 2007; Liu and Tronick 2011; Super 1981)—explicitly promote early social interaction, whereas the chimpanzees mostly have not (Bard 2012).

Responsive care (Bard 1996) was an innovation at the Yerkes nursery in the early 1990s in which all chimpanzees under 1 year of age had an additional 4 h a day, 5 days a week of active interaction with specially trained research assistants. van IJzendoorn et al. (2009) distinguished cohorts of chimpanzee infants that had received standard nursery care from those that had received responsive care. Although “disorganized attachment” was less frequent at 12 months among the responsive care cohort, records from scores on the composite Mental Development Index of the Bayley Scale showed no difference by care regime at 3 months or 4 months (van IJzendoorn et al. 2009:176). When, at 9 months, the chimpanzee subject pool overlapped human norms, those with

36 Hum Nat (2014) 25:28–48

responsive care scored significantly higher than both the standard care cohort and the human standard (2009:180).

Captive care regimes might lead to overestimating differences between human and chimpanzee infants, but they might also lead to underestimation of differences. In captivity, even with mother-rearing, babies can be set down safely, unlike the wild where babies must cling all day long as their mothers travel and forage (Plooij 1984). Takeshita et al. (2009:252) noted that the human pattern of placing babies down on their backs “promotes face to face communication. . . . Moreover, infants in the supine position can interact with other nearby individuals in the same manner from an early age.” As captivity seems to expose similar sensitivities between human and chimpan- zee newborns, so too a shift from independent mothering could have revealed these capacities in ancestral populations (Hrdy 2013), providing phenotypes for directional selection to modify (Chisholm 2003; Fisher 1958; Gould 1977; West-Eberhard 2003). Has it done that?

At the Kyoto University Primate Research Center, where trusting relationships with chimpanzee mothers have allowed researchers to monitor social capacities in mother- reared infants, Tomonaga and colleagues (2004) found remarkable similarities to humans in chimpanzee infant and mother mutual gaze and infant gaze-following through the first 2 months of life. Initially infants matched facial expressions with caregivers as human babies do (Myowa-Yamakoshi et al. 2004), but this declined to chance levels by 2 months of age. The “9 month revolution” when human infants begin to seek joint attention with others on objects of interest “does not seem to occur in chimpanzees. . . . The chimpanzee infants never displayed ‘object showing’ or ‘object giving,’ indicative of referential communication in a triadic relationship in human infants” (Tomonaga et al. 2004:232).

Human infants draw others into joining them in paying attention to things by pointing, behavior labeled shared or “joint attention,” or “triadic engagement.” One hypothesis about why children do this by 9 months or before whereas chimpanzee infants do not is that earlier locomotor competence allows chimpanzee infants to get what they want themselves, whereas human babies must use social means (Leavens et al. 2008). Bard (2012:243) reports that “when chimpanzees are raised with warm relationships and industrially manufactured objects,” mutual triadic engagements are common. Her appraisal is that, in captivity, “young chimpanzees compare favorably to humans as newborns through to 2.5 years olds” (2012:244).

A widely used measure of what youngsters understand is the False Belief Test. The subject and a confederate of the experimenter together watch the experimenter hide a treat. Then the confederate leaves, and the subject sees the experimenter move the treat to a new hiding place. The test question is whether the subject will expect the confederate to look for the treat where they saw it hidden, or where it was moved and rehidden while the confederate was away. Children generally fail to pass it until about 4 years of age, but chimpanzees do not pass it even as adults (Call and Tomasello 2008; Ruiz and Santos 2012). Yet careful experiments show that chimpanzees do know that others can know different things, and they behave accordingly (e.g., Kaminski et al. 2008; Schmelz et al. 2011)—something Hare (2011) called “chimpanzee chess.” The developmental timing of such capacities remains to be determined in chimpanzees. But just as protocols other than the False Belief Test show that chimpanzees recognize that others can know different things than they know, findings with (Western) human

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infants show they can too—by at least 12 months of age, long before they pass the False Belief Test (Baillargeon et al. 2010; Reddy 2008; Tomasello and Haberl 2003).

Human Developmental Psychology

Most human infant development studies are not cross-species comparisons and instead aim to document how and when human babies begin to understand the world and participate in social life. Because language is so central to human interactions, developmentalists are often especially interested in the role of language learning in cognitive ontogeny (e.g., Spelke 2009; Spelke and Kinzler 2007). But many have argued persuasively that the evolution of human language depended on the preceding evolution of distinctive human preferences for shared intentionality (including Tomasello [following Grice 1957] and Hrdy 2009 [following Tomasello]). If so, the focus on language learning leads away from preexisting social appetites that are its foundation.

Observations and systematic protocols to probe the minds of prelinguistic babies reveal very early social sensitivities (e.g., Gopnik et al. 1999; Hamlin et al. 2010, 2011; Reddy 2003, 2008; Sommerville et al. 2005; Trevarthen 1979; Trevarthen and Aitken 2001; Woodward 1999; Wynn 2008). However Konner (2010:214) is not alone in his skepticism about such inferences from similar observations, criticizing Nagy’s (2008) inference of “innate intersubjectivity” from newborn reactions to unresponsively still faces. Instead, Konner concludes that, “our newborns are less competent motorically, socially, and even perceptually than ape newborns” (2010:216).

Motorically, yes (Gómez 2004; Kellogg and Kellogg 1933; van Lawick-Goodall 1968; Takeshita et al. 2009). Plooij (1984) found that even at 8 weeks of age chimpanzee babies had some body-position control and could sit and push off to a standing position from the mother while supporting themselves on her. But the evidence touched on here does not support claims that humans are delayed socially. The developmental timing of attachment may not be very different in chimpanzee and human infants (van IJzendoorn et al. 2009). Human infants also pass the Mark and Mirror Test earlier than chimpanzee infants do (Bard et al. 2006; Lin et al. 1992), and developmental psychologists find evidence that human infants are self-conscious long before they can pass that test (see Reddy 2008: chap. 7 for references and discussion). “Results from many studies suggest that infants treat intentional agents—or, at least, the specific category of human agents—differently from other entities, even in the first days and weeks of life” (Wynn 2008:331, and see further discussion and references therein).

Our Other Closest Living Relative

In his review of the history of ideas around hominid social capacities, Brian Hare (2011) suggested that we might gain insight into “what changed and why” in human cognitive ontogeny by comparing not just humans with apes, but also apes with each other. Of the two species with which we share a most recent common ancestor, bonobos are notably more socially tolerant than chimpanzees (de Waal 2012; Hare et al. 2012; Herrmann et al. 2010b), more like humans on that score. If our higher social tolerance is due to similar shifts in cognitive ontogeny, then developmental timing in humans and bonobos should be shifted in the same direction from chimpanzees, either because

38 Hum Nat (2014) 25:28–48

similar shifts are derived in both humans and bonobos or because chimpanzees are more derived than either of us.

Wobber et al. (2010) investigated development of the social tolerance difference between chimpanzees and bonobos by running experiments on feeding tolerance, social inhibition, and social learning with similarly aged pairs. With youngest subjects 2 to 4 years old, the experimenters found bonobo development to be delayed relative to chimpanzees in all three tasks. Similar tests on human subjects would be confounded by language. But prelinguistic infants show a preference for helpful versus hindering actors by the age of 2 months (Hamlin et al. 2011). That human babies discriminate social opportunities and threats at astonishingly young ages (Gopnik 2009; Reddy 2008) can only be an indirect comparison because directly parallel measures are unavailable for either species of Pan. But Wobber and colleagues (2010:229) are likely right to say that “The crucial cognitive adaptation of humans relative to other apes is the accelerated development of social skills in infants.”

If social discrimination is delayed in more tolerant bonobos compared with chim- panzees, but accelerated in even more tolerant humans compared with either species of Pan, then higher social tolerance goes with timing shifts in opposing directions. The Self-Domestication Hypothesis (Hare et al. 2012) linking selection for reduced aggres- sion and higher social tolerance to developmental delays fits bonobos but not humans. In both Pan species, infants have their mother’s undivided attention as she rears them one at a time without help. According to the hypothesis favored here, accelerated social development in humans evolved along with our distinctive rearing environments. Motivations and capacities for shared intentionality were favored in us and not the other apes as concomitants of our grandmothering life history. While grandmothering propelled delays in other aspects of development, it accelerated development of social emotions and motivations in infancy.

Discussion and Conclusions

Based on behavioral experiments with young (Western) human children and older apes, Tomasello and colleagues continue to add evidence consistent with their argument that shared intentionality is distinctively human. Other comparativists contributing to be- havioral experiments usually use adults of each species. Recent reviews of this growing field are numerous, identifying an array of features as the distinctive scaffolding of human prosociality. Some nominate escalated altruistic preferences (Fehr and Fischbacker 2003; House et al. 2012; Silk 2009) or multiple differences in prosociality, tendency to punish, and concern for fairness (Silk and House 2011). Others highlight punishment (e.g., de Waal and Suchak 2010; Melis and Semmann 2010) or disgust (Sheskin and Santos 2012). Some identify proactive cooperation and reactivity (Jaeggi et al. 2010), emotional reactivity and social tolerance (Hare 2007; Melis et al. 2006), or recognition of benefit from mutualistic endeavors in a wide range of situations (Hare and Tan 2012).

Lack of agreement reflects the difficulty of the comparisons. Even carefully docu- mented differences in social comprehension (Herrmann et al. 2007, 2010a) can be contested on grounds of experimental logistics (de Waal 2011; de Waal et al. 2008). Protocols are carried out in contexts constructed by humans, and usually with human

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participants. Developmental (Bard et al. 2011) and socioecological (Boesch 2012; Wrangham 2010) confounds are continuing issues. The same should be noted for the use of experiments to characterize human sociality since behavior in the lab does not mirror human life outside it (e.g., Kahneman 2012; Wiessner 2009). Concerns about ecological validity, as well as other interpretive difficulties (e.g., Burton-Chellew and West 2013; Leavitt and List 2007; Shettleworth 2010), should be noted more often for our own species. Interpretation is even less straightforward with nonhuman primates (Penn and Povinelli 2007; Penn et al. 2008; Povinelli 2000; Povinelli and Vonk 2003) and prelinguistic infants (Scarf et al. 2012).

Despite the complexity of this literature, there is seeming agreement that humans differ from other apes in our prosocial tendencies, whether or not that difference is best characterized by distinctive human preferences for shared intentionality. Along with general if not universal agreement about this conclusion goes a widely shared assumption that is contested here. Primatologists and developmental psychologists generally attribute the evolution of the human difference to evolutionary benefits conferred in cultural transmission and cultural cooperation. This circularity offers no leverage for explaining why shared intentionality evolved in us and not the other apes. An especially promising alternative hypothesis locates the initial evolution of our distinctive social appetites in the ancestral shift from independent mothering to reliance on help.

In conflict with the idea that human babies are in a uniquely helpless state of exterogestation (Montague 1961), chimpanzees babies are helpless too (Matsuzawa 2012; Schultz 1969). Plooij (1984:56–57) noted that “chimpanzee and man (and possibly the other apes) seem to stand apart from the remainder of the order primates in this respect” and said, “I venture to think that the early development of chimpanzee babies and human babies are almost equally retarded.” We share a broadly apelike helplessness in thermoregulation or “proper clinging” compared with monkeys, and humans have notably slower motor development. But investigators looking for social engagement and interactive participation in human infants find them soon after birth. This sensitivity, like the self-recognition detected by the Mark and Mirror test, may be earlier in humans than in chimpanzees, and likely much earlier than in bonobos.

Hrdy’s hypothesis that distinctively human sociality evolved in response to novel challenges faced by ancestral infants converges with the suggestion that Konner made 40 years ago. Perhaps “characteristic features of adult human behavior have evolved not because they are an ideal adaptation [in adulthood], but because they are the result of an ideal adaptation in infancy” (Konner 1972:302). If infant sociality is the founda- tion of human cooperative capacities, it also makes sequences of mutual attention and intention with particular others central concerns in our lineage alone. This preference for mutual attention can account for our distinctive enthusiasm for doing things “our way” (Nagell et al. 1993; Nielsen and Tomaselli 2010) as well as the in-group bias toward similar others that is present in very young children (Gopnik 2009; Mahajan and Wynn 2012). Although concerns about human cooperation were not central when Konner (1972) focused on Ju/’hoan infant development, he anticipated the speculation that it is these capacities that provide the foundation for the subsequent evolution of human pair ponds when he said, “some adult behavior patterns (for example marriage) may be in part the result of selective forces favoring certain infant behaviors” (1972:302).

40 Hum Nat (2014) 25:28–48

Hypotheses that make selection on infants due to rearing environments central to distinctly human cooperative tendencies contrast with other current ideas about human prosociality. I note especially contrasts with hypotheses that appeal to some form of group selection to explain the human difference (e.g., Boehm 1999; Bowles and Gintis 2011; Haidt 2012; Richerson and Boyd 2005; Sober and Wilson 1998; Wilson 2012). Although those arguments are varied, they often cite Darwin’s 1871 discussion of the evolution of human moral faculties and use his own words as an authoritative source for the need to rely on group selection. Darwin said:

When two tribes of primeval man, living in the same country, came into compe- tition, if one tribe included . . . a greater number of courageous sympathetic and faithful members, who were always ready to warn each other of danger and to aid and defend each other, this tribe would without doubt succeed best and conquer the other. . . . A tribe possessing the above qualities in high degree would spread and be victorious over other tribes; but in the course of time it would, judging from all past history, be in its turn overcome by some other still more highly endowed tribe. Thus the social and moral qualities would tend to slowly advance and be diffused throughout the world (1981:162).

But he continued:

How, it might be asked . . . did a large number of members first become endowed with these social and moral qualities, and how was the standard of excellence raised? . . . It is extremely doubtful whether the offspring of the more sympathetic and benevolent parents, or those which were most faithful to their comrades, would be reared in greater number than the children of selfish and treacherous parents of the same tribe. . . . It seems scarcely possible (bearing in mind that we are not speaking of one tribe being victorious over another) that the number of men gifted with such virtues, or that the standard of their excellence, could be increased through natural selection (1981:163).

Having established the challenge, he proceeded to meet it, suggesting solutions that have a remarkably modern ring. First he suggested reciprocity, but,

there is another and much more powerful stimulus to the development of the social virtues, namely the praise and blame of our fellow-men. The love of approbation and the dread of infamy, as well as the bestowal of praise or blame, are primarily due . . . to the instinct of sympathy; and this instinct no doubt was originally acquired like all other social instincts, through natural selection (1981:164; see also Williams 1966:93–94).

Although there is much yet to learn of social ontogeny in our great ape cousins, developmental psychologists find evidence of sensitivity to praise and blame in very young human babies (Gopnik et al. 1999; Hamlin et al. 2011; Reddy 2003, 2008). It appears well before they have language, even longer before they participate in coop- erative foraging (Tomasello 2009; Tomasello et al. 2012), let alone lethal aggression between groups (Bowles and Gintis 2011). Just as these sensitivities appear earlier in development, the survival advantages they confer on infants are independent of cooperative opportunities at older ages. Their early development is consistent with

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the hypothesis that distinctively human prosociality is a legacy of natural selection on ancestral infants facing the novel rearing environments that came with grandmothering. These links may explain why it was only our lineage that evolved the intersubjective appetites that, once evolved, became foundation for our relationships, our imaginations, and the social and economic interdependence of our lives (Tomasello and Rakocszy 2007).

Acknowledgments I thank especially Nick Blurton Jones and Sarah Hrdy, as well as Ted Coxworth, Steve Beckerman, Karen Kramer, Jim O’Connell, and four anonymous reviewers for helpful comments and good advice.

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48 Hum Nat (2014) 25:28–48

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Homo virtuous? Authors:

Douglas, Kate Source:

New Scientist. 11/10/2012, Vol. 216 Issue 2890, p42-45. 4p. Document Type:

Article Subject Terms:

*ETHICS *ALTRUISM *RESEARCH *BEHAVIOR evolution *SHARING *RECIPROCITY (Psychology) *SOCIAL psychology *OXYTOCIN -- Psychological aspects *SELFISHNESS

Abstract: The article presents an overview of research on the evolution of morality in humans. Topics include evidence of sharing among related animals, the evolution of reciprocal altruism in ancient human groups, and physiological factors such as the production of oxytocin after a good behavior. It is suggested that human behavior is motivated by both selfless and selfish motives, such as prosocial cooperation, fear of punishment, and cultural influences.

Full Text Word Count: 2606

ISSN: 0262-4079

Accession Number: 83356085

Humans are capable of incredible kindness and cruelty. What drove the evolution of our moral compass, asks Kate Douglas

A FEW years ago, I attended a conference on animal behaviour in Atlanta, Georgia. The end-of- meeting party included a trip to the zoo and while we roamed freely between the caged beasts the conference organisers conducted a whimsical poll to discover what animals people thought were the "best" and "worst". As you might expect the nominations were eclectic, but one name cropped up more frequently than any other - Homo sapiens. More striking still, humans were equally likely to end up in the "best" and "worst" categories. Some respondents even chose humans for both.

There is no getting away from it: Homo sapiens is both the basest of animals and the most noble. Ours is a species capable of horrific cruelty, genocide, war, corruption and greed. Yet we can also be caring, kind, fair and philanthropic - more so than any other creature. What lies behind this dual nature?

Our capacity for good and evil has exercised philosophers from Plato and Aristotle to Jean- Jacques Rousseau and Thomas Hobbes, but today some of the most exciting ideas are coming from an understanding of our evolution. In recent years, researchers have addressed such thorny questions as: why would altruism evolve, how did human conscience emerge, why does it feel good to be nice, and what causes us to give in to prejudice and hatred? The potential power of these insights is intriguing. By understanding the kinds of environments that foster the saint rather than the sinner, we can try to create societies that promote our better nature. It's not just a pipe dream. Some evolutionists are already putting their theories into practice.

The key to virtue is altruism. Anyone can do the right thing given enough incentive, but what distinguishes genuinely good deeds is their selfless nature - a rare phenomenon in the wild. Although colonial insects such as bees and ants can show an impressive level of self-sacrifice, the individuals are so closely related that helping others is tantamount to being selfish, at least in evolutionary terms, since it ensures the survival of their own genes. Relatedness can also explain why many birds, and some other animals, will help rear each other's offspring. It is far harder to find generosity extending outside the family. Even our closest evolutionary cousin the chimpanzee is basically selfish, although in one experiment chimps displayed a small amount of altruism similar to that found in young children, being just as likely to pass an object to an unfamiliar chimp even if some physical exertion was required (PLoS Biology, vol 5, p e184). In a nice twist to our preconceptions, vampire bats offer one of the very few bona fide exceptions to the rule, sharing blood meals with their roost-mates (Nature, vol 308, p 181).

Yet humans do appear to behave selflessly. Since the 1980s behavioural economists have used games to assess our altruistic tendencies. First came the "ultimatum game", wherein player A is given some money and told to split it with a second anonymous player B. If B accepts the split, both keep their share, if not, neither gets a cent. It is free money, so B should accept any amount no matter how small and A should offer as little as possible. But that is not what happens. Instead, in university labs around the world, the most common offer is 50 per cent, with an average of around 45 per cent. Even in a refined version of the experiment called the "dictator game", where A can choose either to give half or 10 per cent and B has no option to reject, three

quarters of people make the more generous offer. It would appear that humans are very nice (and not very logical).

But are we really? Generosity may flourish in the sanitised environment of the lab, but experience suggests that people behave somewhat differently in the messy maul of the real world. And, sure enough, the evidence for virtue is less convincing out there. In one study, collectors of sports cards offered dealers a fixed amount of money in exchange for their best card at that price. John List from the University of Chicago found that when the transactions were done under his watchful eye, dealers played fair, coming up with a card that was worth what the collector had offered. But when dealers were not told they were taking part in an experiment, many ripped off their customers. Such cheating was particularly rife when they were off their home turf, away from their day-to-day customers (Journal of Political Economy, vol 114, p 1).

Why be nice?

Anyone who considers humans to be the worst of animals will conclude that people behave well only if they think they are being watched, proving that there is no such thing as altruism. Another interpretation is that we simply need to redefine virtue in biological terms. After all, altruism cannot be without benefit for the do-gooder, otherwise it would not have evolved by natural selection in the first place. Working on this principle, evolutionary biologists have come up with a variety of explanations for human niceness.

The first possibility is rather disheartening. Traditional hunter-gatherer groups tend to consist of closely related individuals, with kin constituting around a quarter of the members (Science, vol 331, p 1286). Individuals who helped their close relatives ended up passing on more genes, including those pushing us to help our own flesh and blood. So, like bees in a hive, we have evolved strong nepotistic instincts and, by this argument, niceness to non-relatives is simply a case of overspill.

However, it takes time and energy to help others, so evolution would have favoured people who made fewer of these costly mistakes, unless the generosity provided benefits that outweighed the costs. Reciprocity might be one such reason to do right by others. It can explain the altruistic behaviour of vampire bats, for example: they starve to death after a couple of nights without a blood meal, so sharing with a roost-mate that is likely to return the favour is an obvious strategy to help them pull through tough periods. Humans live in groups, are highly dependent on others, and we remember who owes us a favour, so we are perfectly placed to benefit from reciprocal altruism. Indeed, it might explain why List's sports-card dealers tended to play fairer on their home turf, where they are likely to bump into customers again.

It's not just our immediate acquaintances we have to worry about when considering the judgemental eyes of others. Humans are incredibly nosy: we like nothing better than to watch those around us and then gossip about our insights to others. This is how reputations are made and destroyed - and reputations matter. Virtues such as generosity, fairness and conscientiousness are universally valued and people seen to display them are rewarded - others like these individuals, want to do business with them and are more sexually attracted to them. So a good reputation can boost your chances of survival and reproduction. Taking this to its logical

conclusion, Christopher Boehm from the University of Southern California, Los Angeles, argues that over the course of evolution rumour and hearsay may have forced us to become more altruistic - albeit in a biological self-serving sort of way.

Besides offering benefits for the individual, altruism would also have determined the way groups competed over resources. Those that pulled together would have beaten groups whose individuals were more selfish, ensuring their survival. This "group selection" has been a controversial idea, but it is increasingly being accepted as an important driving force behind the evolution of altruism, says Edward O. Wilson at Harvard University.

So we have ended up nicer and more caring than chimps. Even so, our egoistic tendencies must still be far stronger than our altruistic ones - after all, natural selection helps those who help themselves. Indeed, by becoming more altruistic, we created an environment where the selfish can enjoy the benefits of cooperative living - be it a share of mammoth meat or an equitable banking system - without paying the costs. Of course, if everyone did this there would be no cooperative group to begin with. That's the dilemma our Jekyll-and-Hyde nature creates, but humans have evolved a few strategies to discourage free riders.

One is our seemingly innate desire to punish those who step out of line. People playing the ultimatum game will often reject mean offers from their partners just to see the Scrooges suffer, even if it means they both lose the prize. In another version of the game, people will even pay their own money to see selfish players punished for their stinginess. In the real world we commonly use gossip, censure and ostracism to punish minor misdemeanours, while the police, courts and prisons impose sentences to discourage more serious crimes. And although our prehistoric ancestors would have lacked institutions to enforce their rules, Boehm believes they used capital punishment as the ultimate sanction against free riders, based on his discovery that many modern hunter-gatherer societies have the death penalty. If he is correct, punishment has made our species a little bit less evil by removing the most antisocial genes from the human gene pool.

Fear of being punished is not the only thing that keeps our inner egoists in check. Often we are virtuous simply because it feels right. "You cooperate because it's a good thing to do," says Herb Gintis at the Santa Fe Institute in New Mexico. He calls this "strong reciprocity" because we end up doing things that are not personally beneficial but will be good for society if everyone does them - things like voting and giving money to people in need. Gintis believes this urge is behind all moral acts. What generates it?

This is where conscience comes in - not the esoteric entity with religious connotations, but an evolved, subconscious risk calculator that helps us weigh up the pros and cons of different moral options. It works like this. We learn the complex social rules of our particular culture and they become linked in our brains with emotions such as pride and honour, shame and guilt, giving them moral significance. These are the scales upon which moral judgements are weighed, and they tip the balance in favour of virtue; vice may be in your better interests, but it is associated with negative emotions, whereas virtue prompts positive ones.

The pleasure we get from performing a good deed is probably induced by a cocktail of neurochemicals but one seems particularly important. Normally associated with feel-good activities such as sex and bonding, the link between oxytocin and morality was discovered a decade ago by Paul Zak at Claremont Graduate University in California. His experiments reveal, among other things, that people with more oxytocin are more generous and caring, and that our oxytocin level increases when someone puts trust in us. Zak describes oxytocin as "the key to moral behaviour".

The mama-bear effect

So it would appear we have a neurobiological mechanism that tricks us into placing other people's interests above our own. This makes us less selfish but, perversely, is also behind some of our most heinous behaviour. That's because the flip side of niceness to members of one's group is nastiness to outsiders. This xenophobia is underpinned by oxytocin too (Science, vol 328, p 1408) and is sometimes called the "mama-bear effect" because it mirrors a parent's urge to defend her offspring against a threat. As a result, the very system that keeps people working for the good of others can promote atrocities such as racism, genocide and war.

One consequence of this evolved conscience is that our concepts of "good" and "evil" are not universally shared, but rooted in the values of our culture. Take fairness. In modern western cultures, we tend to equate it with equity - one for me and one for you - but other cultures have different ideas. When researchers took the ultimatum game to 15 traditional societies around the world, they found that the average offer of player A ranged from 15 per cent in one society to 58 per cent in another (New Scientist, 10 March 2001, p 38).

The fact that people adapt to the values of their culture makes morality a movable feast. What's more we are all members of multiple cultures - from our closest family to the whole nation - so even an individual's moral compass is not fixed. Undoubtedly, some people are more predisposed to virtue than others but in a toxic culture almost everyone is capable of evil, from bullying and corruption to torture and terrorism. On the plus side, the converse is also true: the right cultural context brings out the good in us. That may not seem like a revolutionary insight, but some people believe it could make the world a better place.

Perhaps the most prominent of them is David Sloan Wilson at Binghamton University in New York state. For the past few years he has been applying what we have learned about the evolution of morality to his home city. Like any city, Binghamton has neighbourhoods where antisocial behaviour is rife and others where people actively work to help each other. He has mapped these peaks and valleys of prosociality and found when people move neighbourhoods they adapt their behaviour to fit the local culture. This is exactly what you would expect, given the factors that influence our moral behaviour. "People may want to be prosocial but in an environment where others are not you lose out," says Wilson. His conclusion is radical. "There's no point trying to make individuals more prosocial, you need to increase the prosociality of the entire neighbourhood."

That is exactly what Wilson is trying to do. One approach involves giving residents the opportunity to create parks on local wasteland. These serve both to improve the physical

environment, which Wilson finds has a strong influence on moral behaviour, and provide a common goal to build cooperative communities. Another project aims to make the classroom more cooperative and appealing to underperforming students by implementing Nobel- prizewinning economist Elinor Ostrom's principles of group cooperation. Wilson has also set up the world's first evolutionary think tank, the Evolution Institute, to bring these ideas to policymakers worldwide.

Evolutionary insights underline the importance of other measures to promote virtuous cultures, too. One is to encourage transparency, since we know that being watched puts us on our best behaviour, if only to enhance our reputations. Also crucial is the rule of law, including swift and just punishment for non-compliance (New Scientist, 5 November 2011, p 42). Less obvious, but highlighted by the study of 15 traditional societies, is economic development. "Modern market economies promote freedom, dignity, tolerance and democracy," says Gintis. Even globalisation presents an opportunity for good. People's wider social and information networks mean that the boundaries between groups are breaking down, reducing our xenophobic tendencies.

It will be interesting to see how far evolutionary theory in action can bring out the best in us. What is not in doubt is that our worst side will remain. Evolution has made us both altruistic and selfish - good and evil - and we cannot be otherwise. "It's impossible for us," says Edward O. Wilson. "If virtue was the only evolutionary force we would be angelic robots."

Morality is a moveable feast depending on our society's culture and our circumstances

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By Kate Douglas

Kate Douglas is a feature editor with New Scientist

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