Monday, May 20, 2019

Males with a mother living in their group have higher paternity success in bonobos (but not chimpanzees)

Males with a mother living in their group have higher paternity success in bonobos but not chimpanzees. Martin Surbeck et al. Current Biology, Volume 29, Issue 10, 20 May 2019, Pages R354-R355.

Summary: In many group-living mammals, mothers may increase the reproductive success of their daughters even after they are nutritionally independent and fully grown [1]. However, whether such maternal effects exist for adult sons is largely unknown. Here we show that males have higher paternity success when their mother is living in the group at the time of the offspring’s conception in bonobos (N = 39 paternities from 4 groups) but not in chimpanzees (N = 263 paternities from 7 groups). These results are consistent with previous research showing a stronger role of mothers (and females more generally) in bonobo than chimpanzee societies.

The Illusion of Stable Preferences over Major Life Decisions: Desired fertility is very unstable, but that most people perceive their desires to be stable

The Illusion of Stable Preferences over Major Life Decisions. Maximilian W. Mueller, Joan Hamory Hicks, Jennifer Johnson-Hanks, Edward Miguel. NBER Working Paper No. 25844, May 2019.

Abstract: We examine the stability of preferences over time using panel data from Kenya on fertility intentions, realizations, and recall of intentions. We find that desired fertility is very unstable, but that most people perceive their desires to be stable. Under hypothetical scenarios, few expect their desired fertility to increase over time. Moreover, when asked to recall past intentions, most respondents report previously wanting exactly as many children as they desire today. Biased recall of preferences over a major life decision could have important implications for measuring excess fertility, the evolution of norms, and the perceived need for family planning programs.

We forecast experiencing a greater amount of regret (both affective & cognitive) than we actually experience; predicting more affective regret coincides with lower well-being

Predicting with your head, not your heart: Forecasting errors and the impact of anticipated versus experienced elements of regret on well-being. Tonya M. Buchanan, Joshua Buchanan, Kylie R. Kadey. Motivation and Emotion, May 20 2019.

Abstract: Research suggests that when predicting our future emotions, affective forecasting errors are frequent (Wilson and Gilbert in Adv Exp Soc Psychol 35:345–411, 2003), influence motivation (Wilson and Gilbert in Curr Dir Psychol Sci 14:131–134, 2005), and drive decisions and behaviors (Dunn and Laham Affective forecasting: a user’s guide to emotional time travel, Psychology Press, London, 2006). Regret can fall prey to these same errors (Gilbert et al., in Psychol Sci 15:346–350, 2004). Recent research characterizes two distinct components of regret: an affective element and cognitive element associated with maladaptive and functional outcomes, respectively (Buchanan et al., in Judgment and Decision Making 11:275–286, 2006). We explored forecasting of these elements across two studies. In Study 1, we investigated how accurately individuals forecast each component of regret, and how this relates to well-being. Participants forecasted experiencing a greater amount of regret (including affective and cognitive components) than they actually experienced. Additionally, forecasted (compared to experienced) components of regret uniquely predicted well-being outcomes, suggesting that predicting more affective regret coincides with lower well-being. In Study 2, forecasting errors in overall regret were eliminated by asking participants to focus on cognitive elements of regret prior to forecasting.

Keywords: Regret Affective forecasting Emotion Well-being Motivation

Romantic initiation strategies: Men to a greater degree than women would use direct approaches & women would use indirect ones (having a friend introduce them, waiting for the other to do something)

Men and women’s plans for romantic initiation strategies across four settings. Susan Sprecher, Stanislav Treger, Nicole Landa. Current Psychology, May 20 2019.

Abstract: This study, with a sample (N = 735) of both university students and non-student adults, examined the various strategies that men and women believe they would use to initiate romantic contact with an attractive other in four different settings: social gathering, bar/nightclub, class/workplace, and Facebook. We found that men to a greater degree than women reported they would use direct approaches (e.g., initiate a conversation) and women to a greater degree than men reported they would use the indirect strategy of having a friend introduce them and the passive strategy of waiting for the other to do something. Men’s greater expectation of being direct in relationship initiation (relative to women) was found across the settings. Shyness was associated with the lower likelihood of expecting to be direct in initiation strategies, although the strength of the association was stronger for men than for women and depended on both the particular initiation strategy and the setting. The findings offer insights into the dynamics of relationship development and how plans for initiation strategies may differ for men and women, including the differential influence of shyness on romantic initiation for men and women.

Keywords: Relationship initiation strategies Relationship initiation Gender differences Shyness

Compared with their lower-class counterparts, higher-class individuals were more overconfident, which made them appear more competent & more likely to attain social rank

The social advantage of miscalibrated individuals: The relationship between social class and overconfidence and its implications for class-based inequality. Belmi, Peter,Neale, Margaret A.,Reiff, David,Ulfe, Rosemary. Journal of Personality and Social Psychology, May 20, 2019.

Understanding how socioeconomic inequalities perpetuate is a central concern among social and organizational psychologists. Drawing on a collection of findings suggesting that different social class contexts have powerful effects on people’s sense of self, we propose that social class shapes the beliefs that people hold about their abilities, and that this, in turn, has important implications for how status hierarchies perpetuate. We first hypothesize that compared with individuals with relatively low social class, individuals with relatively high social class are more overconfident. Then, drawing on research suggesting that overconfidence can confer social advantages, we further hypothesize that the overconfidence of higher class individuals can help perpetuate the existing class hierarchy: It can provide them a path to social advantage by making them appear more competent in the eyes of others. We test these ideas in four large studies with a combined sample of 152,661 individuals. Study 1, a large field study featuring small-business owners from Mexico, found evidence that individuals with relatively high social class are more overconfident compared with their lower-class counterparts. Study 2, a multiwave study in the United States, replicated this result and further shed light on the underlying mechanism: Individuals with relatively high (vs. low) social class tend to be more overconfident because they have a stronger desire to achieve high social rank. Study 3 replicated these findings in a high-powered, preregistered study and found that individuals with relatively high social class were more overconfident, even in a task in which they had no performance advantages. Study 4, a multiphase study that featured a mock job interview in the laboratory, found that compared with their lower-class counterparts, higher-class individuals were more overconfident; overconfidence, in turn, made them appear more competent and more likely to attain social rank.

Participants who played digital games more, spent more time logged to the internet, reported higher levels of internet addiction, but lower levels of depression

Games We Play: Wellbeing of Players of Live and Digital Games. Tihana Brkljačić et al. Chapter 6 of Multifaceted Approach to Digital Addiction and Its Treatment, Bahadir Bozoglan. June, 2019. DOI: 10.4018/978-1-5225-8449-0.ch006

Abstract: The aim of this research was to study frequencies of playing live and digital games, and to test for gender differences, to identify the most frequently played games, and to explore association between well-being indicators and frequency of playing. We found low positive association between frequency of playing of live and digital games. Most frequently played live games were various card games, and Shooter games were most frequent among digital games. Male participants played more frequently both live and digital games. Male participants played more action and simulation computer games, while female participants preferred puzzles and card games. Internet addiction was positively correlated to the amount of time spent logged on to the internet, and higher levels of loneliness and depression. Participants who played live games more reported lower levels of depression. Participants who played digital games more, spent more time logged to the internet, reported higher levels of internet addiction, but lower levels of depression.


Van Leeuwen and Westwood (2008, pp 153) state that: “According to the PsychINFO database, in the last 10 years more than 3000 psychological research articles written in English focused on child play, yet only 40 addressed play in adults or the elderly and this was mainly in therapeutic contexts.“ So, we know very little about how, why and what games adults play, and if there is any association between overall well-being and play in adults.

Whitebread (2012) refers to five types of play in children: physical play (e.g. chasing), play with objects (e.g. construction), symbolic play (e.g. playing with words, sounds, drawing), pretence/socio-dramatic play (role playing) and games with rules (e.g. sports, card games, video games).

Although it is known that need for play is not exclusive for young age (van Leeuwen & Westwood, 2008, Sutton-Smith, 2009), and that adults also enjoy play as a type of leisure activity, only in the recent years scholars started to give more attention to adult play and its functions. One of the major concepts studied in this area is playfulness: the personality trait associated with playing behaviour and willingness to engage in play. In various studies playfulness has been found to be associated with positive outcomes. For example, Magnuson and Barnett (2013) found that playfulness is associated with positive coping. Proyer, Brauer, Wolf and Chick (2018) found it is associated with better subjective well-being, and Proyer (2012) found that people who are more playful are also more creative and intrinsically motivated.

Impact of Legalized Abortion on Crime over the Last Two Decades: The cumulative impact of legalized abortion on crime is roughly 45%, a very substantial portion of the roughly 50-55% overall decline from peak in the 1990s

The Impact of Legalized Abortion on Crime over the Last Two Decades. John J. Donohue, Steven D. Levitt. NBER Working Paper No. 25863, May 2019.

Abstract: Donohue and Levitt (2001) presented evidence that the legalization of abortion in the early 1970s played an important role in the crime drop of the 1990s. That paper concluded with a strong out-of-sample prediction regarding the next two decades: “When a steady state is reached roughly twenty years from now, the impact of abortion will be roughly twice as great as the impact felt so far. Our results suggest that all else equal, legalized abortion will account for persistent declines of 1 percent a year in crime over the next two decades.” Estimating parallel specifications to the original paper, but using the seventeen years of data generated after that paper was written, we find strong support for the prediction. The estimated coefficient on legalized abortion is actually larger in the latter period than it was in the initial dataset in almost all specifications. We estimate that crime fell roughly 20% between 1997 and 2014 due to legalized abortion. The cumulative impact of legalized abortion on crime is roughly 45%, accounting for a very substantial portion of the roughly 50-55% overall decline from the peak of crime in the early 1990s.

Shamans as healers: When magical structure becomes practical function. Comments on placebos and shamanism.

Shamans as healers: When magical structure becomes practical function. Nicholas Humphrey. Behavioral and Brain Sciences, Volume 41, 2018 , e77. April 6 2018.

Abstract: Singh’s analysis has much to be said for it. When considering the treatment of illness, however, he begins from a shaky premise about uncontrollability and, so, fails to make the most of what shamanic treatments–as placebos–can deliver. Manvir Singh argues convincingly that shamans tick all of theboxes we might expect of a magical agent with the power to influence events over which normal human beings have no control.Yet, in the case of illness, to which his analysis is the most obvious fit, he seems to have misread the situation. He classes recovery from illness along with winning the lottery and being struck by lightning as an“outcomes that seemingly occur randomly... cannot be accounted for by predictive theories, because the causal forces escape human perception” (sect.3.3.1, para.1). True, illness can strike out of the blue, and there may be little people can do to prevent it.
Once a person has been unlucky enough to be struck down, however, their return to health is not as unpredictable or, for that matter, as uncontrollable as Singh implies.
To summarise:
1. Humans, like all animals, possess a highly effective suite ofinternal physiological healing mechanisms designed to beat back infection and repair bodily damage. This means that most people, most of the time, eventually recover of their own accord, even from serious illness.
2. Healing has intrinsic costs, however. For example, running a temperature to kill invading bacteria requires a 50% increase in metabolism, and antibody production uses up precious nutrients that are difficult to replace. So, although it may desirable for patients to get well as soon as possible, it is essential they keep sufficient resources in reserve to cope with future challenges.
3. To make the best of this, the pace of recovery is regulated by a brain-based “health governor” designed by natural selection to manage the healing budget in the light of environmental information. This governor acts, in effect, like a hospital manager who must decide how to allocate resources on the basis of an inventory of what’s available and a forecast of what the future holds.
4. A major consideration is the prospect of external help, especially if this suggests the present bout of illness will be short lived. Evidence of immediate environmental assets such as protection, food supplies, medicinal drugs, and tender loving care can provide such assurance; but it can be more speculative, as when there is good reason to believe that specific curative forces are being activated by someone else.
5. The health governor is potentially gullible. It cannot necessarily tell the difference between real and fake news or between a reasonable inference based on solid evidence and one based on a lie. This means that an empty promise of cure–a placebo–maybe as effective as a valid promise in speeding up recovery.
6. Human beings have discovered and learned to take advantage of this loophole in the innate health management system. Although the deeper explanation remains hidden from everyone involved, placebo treatments of illness operate widely, at both individual and cultural levels. [...] When patients credit a shaman with supernatural powers to banish illness, they empower the shaman to activate their own innate capacities for self-cure.

Now, Singh has given us the best account yet of the logic that lies behind belief in shamanism. He thereby has provided thebest explanation of why the treatments may, in reality, be able to do what is claimed. Yet, the surprise in this article is that Singh himself makes so little of this. For him, the fact that the treatments actually work is of secondary importance to the fact that everyone thinks they ought to work.
Why does he not make more of the practical benefits of placebo-mediated healing? I suspect it’s because, in the spirit of Claude Levi-Strauss, he is reluctant to concede that shamanism has evolved for dirty utilitarian reasons. He wants to see shamanism as a self-contained logical edifice that stands on its own as an appealing intellectual structure. No matter that it may be a flimsy house of cards; it deserves to survive because it is so theoretically appealing.It is an admirably brave thesis, but I find it unduly purist and, more important, scientifically limiting. By discounting shamanism’s potential for genuine cure, Singh is missing an obvious opportunity to explain not only why it survives as a cultural tradition, but also its historic origins.
Presumably, ever since human ancestors became capable of reflecting on their lived experience of illness, they looked for patterns. Surely, they noticed early on that recovery sometimes could be speeded up by the attentions of a trusted member of the community who did nothing other than bid the illness to depart. With no obvious physical cause to account for this action at a distance,they had to look for other explanations. Given the evidence that an ordinary human apparently was able to exert parahuman control over another person’s body, it might well have made sense to conclude that this human was not as human as he seemed. [...]
This jibes with Singh’s account. Note the difference of emphasis, however: Singh explains why a shaman can be expected to be capable of miraculous healing. Yet, he does not raise the possibility that, historically, healing that appeared miraculous came first, and that it was this that inspired people to invent the concept of a shaman. Given that Singh draws parallels between shamanism and other religions, it’s worth remarking that Jesus Christ was acclaimed as the son of God because he was seen to perform miracles, not the other way around [...].

Gender Differences in Stability of Brain Functional Connectivity: Female volunteers showed significantly higher temporal correlation coefficients than male volunteers, suggesting their brain FCs are more stable over time

F116. Gender Differences in Stability of Brain Functional Connectivity. Yicheng Long, Jie Lisa Ji, Alan Anticevic. Biological Psychiatry, 74th Annual Scientific Convention and Meeting, May 15, 2019, Volume 85, Issue 10, Supplement, Page S258.

Background: Understanding gender differences of the brain’s intrinsic functional architecture may lead to a better understanding of the pathophysiology of many psychiatric disorders whose prevalence differs between genders. Recently, the dynamic brain functional connectivity (FC) has emerged as a major topic in resting-state functional magnetic resonance imaging (rs-fMRI) studies, and possible associations have been reported between several psychiatric disorders and the temporal stability of brain FCs. However, little is known about whether or not there is a gender difference in brain FC stability.
Results: Female volunteers showed significantly higher temporal correlation coefficients than male volunteers [...], suggesting their brain FCs are more stable over time.

Check also Gender differences in brain functional connectivity density. Dardo Tomasi, Nora D. Volkow. Human Brain Mapping, March 21 2011.
Abstract: The neural bases of gender differences in emotional, cognitive, and socials behaviors are largely unknown. Here, magnetic resonance imaging data from 336 women and 225 men revealed a gender dimorphism in the functional organization of the brain. Consistently across five research sites, women had 14% higher local functional connectivity density (lFCD) and up to 5% higher gray matter density than men in cortical and subcortical regions. The negative power scaling of the lFCD was steeper for men than for women, suggesting that the balance between strongly and weakly connected nodes in the brain is different across genders. The more distributed organization of the male brain than that of the female brain could help explain the gender differences in cognitive style and behaviors and in the prevalence of neuropsychiatric diseases (i.e., autism spectrum disorder).

Both men & women found heroic targets to be more desirable than targets low in heroism (stronger effect for women than men); high heroic targets were rated as more desirable for long-term compared to short-term relationships

Bhogal, Manpal S. 2019. “Further Support for the Role of Heroism in Human Mate Choice.” PsyArXiv. May 19. doi:10.31234/

Abstract: Previous research has explored the role of prosociality in mate choice, predominantly focusing on the role of altruism. Although there is ample evidence to suggest altruism has evolved via mate choice, little research has unpacked prosociality by exploring the role of heroism in mate choice. Limited studies have been conducted in this area, and no studies have explored men’s desirability towards heroic targets. The aim of this study was to replicate and extend the limited research on the role of heroism in mate choice. Participants (n=276, 101 men and 175 women) rated several scenarios varying in heroism, whereby they were asked to rate how desirable targets were for a short-term and long-term relationship. The findings show that both men and women found heroic targets to be more desirable than targets low in heroism, although the main effect of sex was stronger for women than men. Furthermore, high heroic targets were rated as more desirable for long-term compared to short-term relationships, thus replicating and extending previous research. The findings add support to the adaptive role of heroism in human mate choice by exploring the role of heroism in both male and female mate choice. Data, materials, and the preregistered hypotheses/protocol are available on the Open Science Framework (

Divine Placebo: Health and the Evolution of Religion

Divine Placebo: Health and the Evolution of Religion. Patrik Lindenfors. Human Ecology, April 2019, Volume 47, Issue 2, pp 157–163.

Abstract: In this paper, I draw on knowledge from several disciplines to explicate the potential evolutionary significance of health effects of religiosity. I present three main observations. First, traditional methods of religious healers seldom rely on active remedies, but instead focus on lifestyle changes or spiritual healing practices that best can be described as placebo methods. Second, actual health effects of religiosity are thus mainly traceable to effects from a regulated lifestyle, social support networks, or placebo effects. Third, there are clear parallels between religious healing practices and currently identified methods that induce placebo effects. Physiological mechanisms identified to lie behind placebo effects activate the body’s own coping strategies and healing responses. In combination, lifestyle, social support networks, and placebo effects thus produce both actual and perceived health effects of religiosity. This may have played an important role in the evolution and diffusion of religion through two main pathways. First, any real positive health effects of religiosity would have provided a direct biological advantage. Second, any perceived health effects, both positive and negative, would further have provided a unique selling point for ‘religiosity’ per se. Actual and perceived health effects of religiosity may therefore have played an underestimated role during the evolution of religiosity through both biological and cultural pathways.

Keywords: Evolution Cultural evolution Health Placebo Religiosity Social support networks Lifestyle