Death among primates: a critical review of non‐human primate interactions towards their dead and dying

Death among primates: a critical review of non‐human primate interactions towards their dead and dying. André Gonçalves, Susana Carvalho. Biological Reviews, April 4 2019. https://doi.org/10.1111/brv.12512

ABSTRACT: For the past two centuries, non‐human primates have been reported to inspect, protect, retrieve, carry or drag the dead bodies of their conspecifics and, for nearly the same amount of time, sparse scientific attention has been paid to such behaviours. Given that there exists a considerable gap in the fossil and archaeological record concerning how early hominins might have interacted with their dead, extant primates may provide valuable insight into how and in which contexts thanatological behaviours would have occurred. First, we outline a comprehensive history of comparative thanatology in non‐human primates, from the earliest accounts to the present, uncovering the interpretations of previous researchers and their contributions to the field of primate thanatology. Many of the typical behavioural patterns towards the dead seen in the past are consistent with those observed today. Second, we review recent evidence of thanatological responses and organise it into distinct terminologies: direct interactions (physical contact with the corpse) and secondary interactions (guarding the corpse, vigils and visitations). Third, we provide a critical evaluation regarding the form and function of the behavioural and emotional aspects of these responses towards infants and adults, also comparing them with non‐conspecifics. We suggest that thanatological interactions: promote a faster re‐categorisation from living to dead, decrease costly vigilant/caregiving behaviours, are crucial to the management of grieving responses, update position in the group's hierarchy, and accelerate the formation of new social bonds. Fourth, we propose an integrated model of Life‐Death Awareness, whereupon neural circuitry dedicated towards detecting life, i.e. the agency system (animate agency, intentional agency, mentalistic agency) works with a corresponding system that interacts with it on a decision‐making level (animate/inanimate distinction, living/dead discrimination, death awareness). Theoretically, both systems are governed by specific cognitive mechanisms (perceptual categories, associative concepts and high‐order reasoning, respectively). Fifth, we present an evolutionary timeline from rudimentary thanatological responses likely occurring in earlier non‐human primates during the Eocene to the more elaborate mortuary practices attributed to genus Homo throughout the Pleistocene. Finally, we discuss the importance of detailed reports on primate thanatology and propose several empirical avenues to shed further light on this topic. This review expands and builds upon previous attempts to evaluate the body of knowledge on this subject, providing an integrative perspective and bringing together different fields of research to detail the evolutionary, sensory/cognitive, developmental and historical/archaeological aspects of primate thanatology. Considering all these findings and given their cognitive abilities, we argue that non‐human primates are capable of an implicit awareness of death.


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III. PRIMATE THANATOLOGY:CONTEMPORARY REPORTS 

(1) Dead infants
 Females of several primate species have been observedpersistently to carry their deceased infants (sometimesfor prolonged periods of 10 days or more), regardlessof the circumstances that caused the fatality (Fig. 2). Otherrecorded behaviours include grooming, swatting flies awayfrom the corpse and sometimes even consuming part of it.Primatologists have described their expressions as ‘puzzled’,‘confused’ or ‘dazed’, which raises the question as to whetherthey have some, if any, understanding of death.These behaviours are striking because they seemmaladaptive. Whilst live infants are energetically costlyto the mothers who carry them, ultimately they increasereproductive fitness – something a dead immature offspringcannot do. Holding a lifeless corpse hinders locomotion,negatively impacting foraging and predator avoidance. Somewill solve these difficulties by adopting a tripedal gait, carryingthe corpse ventrally, using the neck and shoulder to wedgeit, drag it along the ground, or even carry it dorsally usingthe tail as an extra limb. While some hypotheses have beenproposed to explain post-mortem carrying (Table 1), it isstill a matter of debate which one offers the most powerfulexplanation. Because some are mutually non-exclusive it islikely that many factors, depending on context, contribute tothese behaviours (see Watson & Matsuzawa, 2018).








 
(a)Mother – infant dynamics
 Dead-infant carrying is the most prevalent thanatologicalbehaviour distributed in several primate taxa (Fig. 3). Thisshould not be surprising since: (i) primates follow a typicaltrend observed in many vertebrate species of high infantmortality (Bronikowskiet al., 2011); and (ii) unlike adolescentsand adults who are abandoned at their site of death, deadinfants and juveniles are usually carried by the mother forlonger durations, allowing easier detection. Nevertheless, themother will, invariably, cease to carry the corpse, leavingit unattended for progressively longer periods until finallyabandoning it (Jay, 1962; Nash, 1974; Green, 1975; Altmann,1980; Hosakaet al., 2000; Croninet al., 2011).Many authors have claimed that the mother ceases totreat her infant as a live one during this period – carryingit in awkward positions, by the leg or tail, upside down,using the mouth or dragging the corpse along the ground(van Lawick-Goodall, 1968; Green, 1975; Altmann, 1980;Luet al., 2007; Perry & Manson, 2009; Biroet al., 2010;Fashinget al., 2011). Green (1975), who conducted acomprehensive vocal study with wild Japanese macaques(Macaca fuscata), noted that mothers gave out particularvocalisations when their infants died, repeated whilst carryingthe infant or distant from it. Some have proposed thatinfantile colouration may elicitpost-mortemcarrying (Jay,1962; Alley, 1980; Rajpurohit, 1997), but this does notexplain why such behaviour occurs in females from myriad
primate species – some with flamboyant natal coats andothers non-conspicuous.Perry & Manson (2009) describe a case of a capuchinfemale (Cebus capucinus) carrying her stillborn, arguing thatshe behaved in ways which suggested an awareness ofher infant’s death, such as letting the infant be fullysubmerged in water. Although this could represent causalattribution, it may equally be a failure of perspectivetaking. Inexperienced Japanese macaque mothers havebeen observed to inadvertently drown their infants whendiving into the hot springs of Jigokudani Park for food (deWaal, 1996) and similar occurrences have been reportedamong baboons (Cheney & Seyfarth, 2007). Moreover,filial cannibalism duringpost-mortemcarrying has also beenwitnessed, suggesting that corpses may be re-categorisedas food (Altmann, 1980; Hsiang-Jen & Hsiu-Hui, 2008;Dellatore, Waitt & Foitova, 2009; Watsonet al., 2015; Tianet al., 2016; Tokuyamaet al., 2017; De Marco, Cozzolino &Thierry, 2018; Watson & Matsuzawa, 2018).Croninet al.(2011) propose that whilst displayingapproach – withdrawal behaviour towards the infant, themother is actively gathering novel death cues that she couldconceivably recall in equal situations (i.e. death of anotherconspecific). However, if the purpose of such knowledge isto prevent costly behaviours, findings from Sugiyamaet al.(2009) that there is no significant difference in carryingduration between younger and older mothers suggests that,at least in Japanese macaques, no such learning component was found. Moreover, reports on chimpanzees from Bossouillustrate that there may be an individual component. Of thefive infants that died during a flu epidemic, only two werecarried for extended periods (Biro, 2011). Jire transportedboth her dead infants: Jokro in 1992 and again Jimatoin 2003 (Matsuzawa, 1997; Biroet al., 2010). Similarly,in semi-ranging Japanese macaques, the same female wasreported carrying her dead infant for extended periods in2011 and again in 2013 (Watsonet al., 2015), although otherfactors such as cause of death could impact these responses(see Section III.1e).

(b)Group – infant dynamics 
The behaviour of group members who were not emotionallyinvolved with the infant is also of interest. Cheney & Seyfarth(2007) note that wild chacma baboons (Papio h. ursinus)donot attempt to handle dead infants and rarely grunt atthem as they would live infants. Similarly, Rajpurohit (1997)mentions that in Hanuman langurs, other members showlittle interest in dead infants – a finding also reported inother species (van Lawick-Goodall, 1968; Green, 1975;Luet al., 2007; Guoet al., 2016; De Marcoet al., 2018).Conversely, infants and juveniles express more interest inthe corpse (van Lawick-Goodall, 1968; Ciani, 1984; Croninet al., 2011; Liet al., 2012), some even playing with it (vanLawick-Goodall, 1971; Hosakaet al., 2000; Biro, 2011).Furthermore, juvenile and nulliparous adult females havebeen witnessed carrying dead infants relinquished by theirmothers (Warren & Williamson, 2004; Fashinget al., 2011).The mother occasionally restricts attempts by other groupmembers to access the corpse (Altmann, 1980; Gupta,2000; Liet al., 2012; Tokuyamaet al., 2017) (Fig. 4), withsiblings having broader admittance (van Lawick-Goodall,1971; Kano, 1992; Mulleret al., 1995; Matsuzawa, 1997). It is conceivable that such playful interactions may prepareyounger individuals for death recognition.The matter of stench avoidance is divisive. Byrne (2016)recounts a case in western lowland gorillas where the groupmembers, after initial interest, seemed to avoid and shunthe carrying mother after the body started to smell. BothGreen (1975) and Sugiyamaet al.(2009) report that Japanesemacaque group members actively avoided the mother of adead infant, presumably because of the putrid smell from thecorpse. However, among chimpanzees (Biroet al., 2010) andGelada baboons (Theropithecus gelada) (Fashinget al., 2011),no such avoidance is reported. That most mothers abandonthe infant within a week of death is also informative sinceduring this period the cadaver goes from bloating to activedecay – the stage of decomposition that emanates the moststench.Infant corpses are sometimes central to or incorporatedin the displays of male chimpanzees (Bygott, 1972;Matsuzawa, 1997). Adult males have also been known tocarry dead infants; most notably in semi-ranging Barbarymacaques (Macaca sylvanus) whilst interacting with othermales where the corpse is used for agonistic bufferingpurposes (Merz, 1978). In conjunction with other reports,Merz (1978) notes that handling was much rougher andof shorter duration than with live infants. Rare cases haveinvolved high-ranking individuals unsuccessfully adoptinglive orphans and continuing to carry them after death (Tayloret al., 1978; Notman & Munn, 2003). 

(c)Old World – New World dichotomy 
To the best of our knowledge, there are 13 publishedcases of dead-infant carrying among New World monkeys,comprising cebids, and atelids (see online Supportinginformation, Appendix S1). The lack of information on thisbehaviour may be partly due to the smaller numberof publications on New World primates. Anderson (2011)argues that their tropical habitats accelerate the decay ofcorpses and consequently their abandonment. Additionally,while Old World monkeys can be either arboreal, terrestrialor both, New World monkeys are almost exclusively arboreal(Fernandez-Duque, Di Fiore & Huck, 2012). Referring toan arboreal Old World species, the red colobus (Piliocolobustephrosceles), Struhsaker (2010) pointed out the difficulty ofcarrying a dead infant while leaping between trees – aclaim supported by other colobine cases (Colobus guereza:Onderdonk, 2000;Colobus vellerosus: Teichroeb & Sicotte,2008) and the observation that species that carry their deadfor long periods, such as snub-nosed monkeys (Rhinopithecusbieti) tend to be more terrestrial (Long & Kirkpatrick, 1994).Observer bias may also be involved; when reviewing theliterature on post-mortem carrying, the best-representedspecies were semi or fully terrestrial and inhabited accessibleareas or were in close proximity to human communities(Rajpurohit, 1997; Sugiyamaet al., 2009; Fashinget al.,2011). The only case of dead-infant carrying recordedamong prosimians comes from ring-tailed lemurs (Lemur catta)(Nakamichiet al., 1996), the most terrestrial lemur (Schmidt,2011). 

(d)Non-carriers 
Not all primates engage in corpse carrying althoughthere is evidence that they do show behavioural responsesto dead or dying infants (see Appendix S2). Strepsirrhinesand callitrichines generally do not carry dead infants, despitesome unsuccessful attempts at carrying having been reported.Nakamichi, Koyama & Jolly (1996) observed seven cases ofring-tailed lemur behaviour towards dead/dying infants.One individual carried her dying infant tripedally for 15 m,whilst others in the troop showed affectionate behaviours,gave cohesion calls and displayed ambiguous back-and-forthmovements, switching between following the troop andreturning to the infant, sometimes for hours. Similarly,Santini (2012) observed a dying ring-tailed lemur infantrepeatedly fall, vocalise, and attempt to climb onto theback of its mother, who wavered between staying withthe infant or the group, eventually choosing the latter.Additionally, Littlefield (2010) observed two infanticides insifakas (Propithecus verreauxi) where the females stayed withthe dying infant, occasionally grooming it and, after itsdeath, remaining with the corpse before giving cohesion callsand then following the group. In experimental settings withvarious prosimians, Rosenson (1977) noted that, whilst noneof the mothers attempted to carry their dead infants, all wereobserved to groom them; a galago (Otolemur crassicaudatus)retrieved her infant using her jaws (later and dropping itwhen attempting to groom), and a black lemur (Eulemurmacaco) was seen gripping and lifting her infant. Groomingwas observed in all mothers, most of which were in regularcontact with their infants, likely representing an attemptto elicit a response. While it seems strepsirrhines lack themorphological proficiency for extended periods of carrying,their behaviour suggests they are not indifferent to their deador dying infants, even after they stop showing signs of life(Nakamichi, 2016).

To defend their views, Rousseauians resort to a variety of tactics to diminish the apparent frequency & intensity of hunter-gatherer warfare (redefine war, censor ethnographic accounts of warfare, misconstrue archaeological evidence)

Pacifying Hunter-Gatherers. Raymond Hames. Human Nature, April 5 2019.https://link.springer.com/article/10.1007/s12110-019-09340-w

Abstract: There is a well-entrenched schism on the frequency (how often), intensity (deaths per 100,000/year), and evolutionary significance of warfare among hunter-gatherers compared with large-scale societies. To simplify, Rousseauians argue that warfare among prehistoric and contemporary hunter-gatherers was nearly absent and, if present, was a late cultural invention. In contrast, so-called Hobbesians argue that violence was relatively common but variable among hunter-gatherers. To defend their views, Rousseauians resort to a variety of tactics to diminish the apparent frequency and intensity of hunter-gatherer warfare. These tactics include redefining war, censoring ethnographic accounts of warfare in comparative analyses, misconstruing archaeological evidence, and claiming that outside contact inflates the intensity of warfare among hunter-gatherers. These tactics are subject to critical analysis and are mostly found to be wanting. Furthermore, Hobbesians with empirical data have already established that the frequency and intensity of hunter-gatherer warfare is greater compared with large-scale societies even though horticultural societies engage in warfare more intensively than hunter-gatherers. In the end I argue that although war is a primitive trait we may share with chimpanzees and/or our last common ancestor, the ability of hunter-gatherer bands to live peaceably with their neighbors, even though war may occur, is a derived trait that fundamentally distinguishes us socially and politically from chimpanzee societies. It is a point often lost in these debates.

Keywords: Hunter-gatherers War Chimpanzees Peace Comparative research

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In 1997 Lawrence Keeley coined the phrase “pacifying the past” as a critique of scholars who took what one might call a Rousseauian view of conflict in small-scale societies that predated the advent of the state. Along with such notions as living in harmony with the environment (Hames2007) and primordial sexual equality and promiscuity (Ryan andJetha2012 ), Rousseauians believed that war and lethal violence were rare or absent in
small-scale societies and did not become widespread and intense until settled agricultural life when war was “invented” and then elaborated and intensified with the development of the state. Keeley’s direct experience with this perspective stemmed from his research grants being rejected by funding agencies because he sought to investigate what he hypothesized to be defensive fortifications and other forms of archaeological evidence of warfare in non-state societies. Although his War before Civilization (Keeley1997) made a significant impact, those who hold the Rousseauian position have responded, and a major target has revolved around the intensity and frequency of warfare and lethal violence among mobile hunter-gatherers. The terms “Hobbesians” and “Rousseauians” have gained some currency (Gat2015), although alternative contrasts such as Hawks and Doves (Otterbein2004 ) or warfare having a “long chronology” or “short chronology”(Allen and Jones2014 ) make similar distinctions (see Allen2014afor a review of these positions). However, I will use theHobbesian/Rousseauian distinction following the penetrating analysis by Gat (2015) wherein he uses the Australian hunter-gatherer material to clearly expose conceptual and empirical problems for those who would pacify hunter-gatherers. Oddly, Douglas Fry, one of the Rousseauian leaders of this conservative counter, claims that the “pervasive intergroup hostility model”is somehow the main orientation held by many researchers (2006 :10) who investigate hunter-gatherer warfare. Although this allegedly pervasive model includes such things as hunter-gatherer patrilocality and the closed nature of residential bands, the key claim he seeks to refute is that warfare has a deep history and was common among mobile hunter-gatherers. How one demarcates “common” from “rare”is not defined by Fry, even though comparative researchers have created measures of both warfare frequency, or how often it occurs (e.g., Ember and Ember1992a), and warfare intensity, or the probability of an individual being killed by another human through war or homicide (Wrangham et al.2006).
This Rousseauian perspective runs parallel to scholars who cast doubt on the causes,adaptive nature, and intensity of chimpanzee coalitionary violence. A number of researchers, most prominently Power (2005 ), claim chimpanzee violence is not “natural”or adaptive and is largely the consequence of outside factors such as research team presence and disruptions (e.g., feeding stations) or disturbances by farmers or the bush meat trade (Sussman and Marshack2010). Such claims have been empirically discounted through a comparative analysis of 22 chimpanzee communities with and without significant contact (Wilson et al.2014 ). Similarly, as applied to hunter-gatherers, tribal zone theory (Ferguson and Whitehead1991 ) makes a parallel claim: tribal warfare was frequently initiated or intensified as a consequence of colonial invasions. 
The goal of this paper is to assess and critique a variety of positions put forward by Rousseauians to diminish the frequency and intensity of warfare among hunter-gatherers. These tactics include the following: misrepresenting evolutionary theory, reclassifying hunter-gatherers; redefining warfare; censoring ethnographic accounts on hunter-gatherer violence; overemphasizing the role of colonial activities in increasing warfare; and questionable use of archaeological evidence and time lines. Finally, and most importantly, I will also argue that although coalitionary violence is a primitive feature of human life that is likely a continuation of the chimpanzee pattern of intergroup relations, the ability to have peaceful relations with neighboring bands is a unique derived trait that fundamentally distinguishes chimps from humans and may have been partially responsible for our rapid cultural evolution.

Echo chambers? Data on Poland & Hungary do not support the hypothesis of clusters emerging along partisan lines; there are sharp group divisions on Twitter, but the nodes however are diverse & overlapping in terms of political leaning

Are Echo Chambers Based on Partisanship? Twitter and Political Polarity in Poland and Hungary. Paweł Matuszewski, Gabriella Szabó. Social Media + Society, April 4, 2019. https://doi.org/10.1177/2056305119837671

Abstract: In this study, we investigate how Twitter allows individuals in Hungary and Poland to experience different political views. To comprehend citizens’ exposure to political information, “who’s following who?” graphs of 455,912 users in Hungary (851,557 connections) and 1,803,837 users in Poland (10,124,501 connections) are examined. Our conceptual point of departure is that Twitter follower networks tell us whether individuals prefer to be members of a group that receives one-sided political messages, or whether they tend to form politically heterogeneous clusters that cut across ideological lines. Methodologically, such connections are best studied by means of computer-aided quantitative research complemented by the sociocentric approach of network analysis. Our data date from September 2018. The findings for Poland do not support the hypothesis of clusters emerging along partisan lines. Likewise, the Hungarian case reveals sharp group divisions on Twitter, the nodes however are diverse and overlapping in terms of political leaning. The data suggest that exposure and segregation in follower networks are not necessarily based on partisanship.

Keywords: Twitter, political information-seeking, network analysis, Hungary, Poland, echo chamber

Female Sexual Dysfunction seems less prevalent among female adult entertainers than rates commonly quoted for the general population and was more often seen in the women with less satisfying personal sex lives

Dubin JM, Greer AB, Valentine C, et al. Evaluation of Indicators of Female Sexual Dysfunction in Adult Entertainers. J Sex Med 2019;XX:XXX–XXX.
https://doi.org/10.1016/j.jsxm.2019.03.002

Abstract
Introduction: Female sexual dysfunction (FSD) incorporates a wide range of sexual issues within the female population; however, it has not been evaluated among female adult entertainers.

Aim: To evaluate the prevalence of FSD in women working in the adult entertainment industry.

Methods: A 53-question online survey was distributed to female adult entertainers via e-mail through collaboration with the Free Speech Coalition, the North American Trade Association of the Adult Industry. Surveys were sent by the Free Speech Coalition to those within the Performer Availability Screening Services database who met the criteria of having biological vaginas and having experience as adult entertainers. The surveys were answered anonymously. Statistical analysis was performed with Stata/IC 15.1.

Main Outcome Measures: The survey acquired baseline characteristics, use of contraceptives, sexual activity, work vs home sexual satisfaction, and orgasm, in addition to evaluation of female sexual function using the Female Sexual Function Index survey, with a total score <26.55 indicative of FSD.

Results: Of the 147 respondents, 96 (65%) met inclusion criteria of adequately completing the survey, having a biological vagina, and working in the adult entertainment industry. The mean age was 34.1 ± 10.3 years (range 20–66). The average Female Sexual Function Index score was 28.7 ± 5.6, and 24.0% (23 of 96) of entertainers had scores indicative of FSD. Overall, women found their personal sex lives more satisfying when compared with their professional sex lives (3.99 ± 1.40 vs 3.08 ± 1.52, P < .01). When comparing women with FSD to those without FSD, women with FSD had less sexual satisfaction at home (2.8 ± 1.7 vs 4.4 ± 1.0, P < .01), fewer overall sexual events (7.0 ± 6.7 FSD vs 12.9 ± 10.0 non-FSD, P < .01), and fewer satisfying sexual events overall (3.3 ± 4.2 vs 10.7 ± 8.7, P < .01).

Clinical Implications: FSD is prevalent among all women, including those within the adult entertainment industry, and must be addressed during patient interactions.

Strength & Limitation: This is the first study to evaluate the novel group of female adult entertainers. Despite this novel population, the study size is rather small and is susceptible to response bias.

Conclusion: FSD appeared to be less prevalent among female adult entertainers than rates commonly quoted for the general population and was more often seen in the women with less satisfying personal sex lives.

Post-menopausal women provide more care to their kin: Evidence of grandparental caregiving from two large-scale national surveys

Do post-menopausal women provide more care to their kin?: evidence of grandparental caregiving from two large-scale national surveys. Marlise K. Hofer et al. Evolution and Human Behavior, April 4 2019. https://doi.org/10.1016/j.evolhumbehav.2019.04.002

Abstract: Drawing on the logical principles of life-history theory, it may be hypothesized that—compared to pre-menopausal women—post-menopausal women will spend more time caring for grandchildren and other kin. This hypothesis was tested in two studies, on results obtained from two large datasets documenting altruistic behaviors of pre-menopausal and post-menopausal women in the United States (N = 7, 161) and Australia (N = 25, 066). Results from both studies revealed that (even when controlling statistically for age, health, financial resources, and other pertinent variables), post-menopausal women devoted more time to grandparental caregiving. This effect was specific to kin care: Menopause status was not as strongly related to a measure of non-kin-directed altruistic behavior (time spent volunteering). These results provide the first empirical support for a previously-untested behavioral implication of menopause.

Young Norway students in college: No indication of women playing hard-to-get, or of strategically downplaying signals of sexual attraction; little evidence of male sexual overperception

Bendixen, M., Kennair, L. E. O., Biegler, R., & Haselton, M. G. (2019). Adjusting signals of sexual interest in the most recent naturally occurring opposite-sex encounter in two different contexts. Evolutionary Behavioral Sciences, Mar 2019, http://dx.doi.org/10.1037/ebs0000162

Abstract: Sexual signaling is subject to manipulation, and miscommunication may occur because of biased interpretations of signals, or because of strategical downplaying of sexual interest (playing hard-to-get). In this article, we examined initial perceptions of cues from opposite sex partners along with participant reported own sexual attraction and signaled attraction in their most recent naturally occurring potentially sexual opposite sex encounter. Data on heterosexual Norwegian male and female students were collected in two largely different social contexts (during Regular Study Period, Spring 2015: N = 224; during Freshmen Weeks, Early Fall 2015: N = 211). Results show no indication of women playing hard-to-get, or of strategically downplaying signals of sexual attraction. There was evidence of male sexual overperception in Study 1, but this effect was not replicated in Study 2 mainly due to increased levels of sexual attraction in single, freshmen women in that particular social context. For both sexes, reported levels of signaled attraction strongly reflected reports of own sexual attraction. Predictors for who ended up having sex after the encounter differed for women and men. For women, ending up having sex was predicted by the other’s short-term mate value, being freshman, and level of perceived sexual interest from the other after the encounter. For men, ending up having sex was predicted merely by their history of casual sex. It is concluded that women and men adjust their signals of sexual attraction upward or downward relative to their felt attraction to prompt further communication and to gain more information.

The reasons that prevent people from cheating on their partners: An evolutionary account of the propensity not to cheat

The reasons that prevent people from cheating on their partners: An evolutionary account of the propensity not to cheat. Menelaos Apostolou, Rafaella Panayiotou. Personality and Individual Differences, Volume 146, 1 August 2019, Pages 34-40. https://doi.org/10.1016/j.paid.2019.03.041

Highlights
•    Finds 47 reasons that prevent people from cheating
•    Classifies reasons for not cheating in broader factors and domains
•    Finds that women have a higher propensity not to cheat than men
•    Finds that conscientiousness and openness predict the propensity not to cheat

Abstract: Infidelity is a widespread phenomenon across different cultures. Yet, not all people are unfaithful to their partners, and the current study aims to identify the reasons that motivate individuals to hold back from cheating. For this purpose, we developed an evolutionary theoretical framework which could enable a better understanding of the ultimate reasons that motivate people not to cheat on their partners. Furthermore, using a combination of qualitative research methods, we have identified 47 proximate reasons that could prevent people from cheating. By using quantitative research methods in a sample of 576 Greek-speaking participants, we classified these reasons in eight broad factors and two broader domains. One domain reflected considerations about the potential costs of cheating, and the other, considerations about the benefits of the current relationship. Women indicated a higher propensity not to cheat than men, especially if they were satisfied with their relationship, and because they would feel guilty. We also found that, the higher participants scored in conscientiousness the lower their propensity to cheat was, while the higher participants scored in openness the higher their propensity to cheat was.

Human Ingenuity and the Search of Prosperity Ended Drought and Famine in India, despite the doomsayers saying we are all going to die due to El Nino–Southern Oscillation and other events

Drought and Famine in India, 1870–2016. Vimal Mishra et al. Geophysical Research Letters, Jan 22 2019. https://doi.org/10.1029/2018GL081477

Abstract: Millions of people died due to famines in India in the nineteenth and twentieth centuries; however, the relationship of historical famines with drought is complicated and not well understood. Using station‐based observations and simulations, we reconstruct soil moisture (agricultural) drought in India for the period 1870–2016. We show that over this century and a half period, India experienced seven major drought periods (1876–1882, 1895–1900, 1908–1924, 1937–1945, 1982–1990, 1997–2004, and 2011–2015) based on severity‐area‐duration analysis of reconstructed soil moisture. Out of six major famines (1873–74, 1876, 1877, 1896–97, 1899, and 1943) that occurred during 1870–2016, five are linked to soil moisture drought, and one (1943) was not. The three most deadly droughts (1877, 1896, and 1899) were linked with the positive phase of El Niño–Southern Oscillation. Five major droughts were not linked with famine, and three of those five nonfamine droughts occurred after Indian independence in 1947.

Plain Language Summary: India witnessed some of the most famous famines during the late nineteenth and early twentieth centuries. These famines caused millions of deaths primarily due to widespread crop failure. However, the role of agricultural drought in these famines remains unrecognized. Using station‐based observations and simulations from a hydrological model, we reconstructed agricultural droughts and established a linkage between famines and droughts over India. We find that a majority of famines were caused by large‐scale and severe soil moisture droughts that hampered the food production. However, one famine was completely due to the failure of policy during the British era. Expansion of irrigation, better public distribution system, rural employment, and transportation reduced the impact of drought on the lives of people after the independence.

There is a significant gap in happiness levels between religious and nonreligious individuals when they are diagnosed with a disability; it reduces happiness for nonreligious people more than that for religious people

The Effect of Becoming Disabled on the Subjective Well-Being of Religious and Nonreligious People. DaeHwan Kim. Journal of Religion and Health, April 4 2019. https://link.springer.com/article/10.1007/s10943-019-00808-8

Abstract: Positive associations between religiosity and subjective well-being (SWB) have been found in a multitude of studies. However, there has been little effort in documenting the role that religion plays in helping people during the onset of adverse circumstances in their lives. This study investigates the effect of religion on the SWB of the disabled. We utilized secondary data from the Korean Longitudinal Study of Aging from 2006 to 2016 with a sample size of 36,484. Starting with nondisabled participants, we applied a difference-in-differences approach to a fixed-effects model and compared the magnitude of the decrease in SWB resulting from disability between religious individuals and their nonreligious counterparts. The empirical results show that following a religion increased SWB by 0.94 (p < 0.01) and the onset of a disability reduced SWB by 3.57 (p < 0.01) out of 100. Furthermore, there is a significant gap in happiness levels between religious and nonreligious individuals when they are diagnosed with a disability. Becoming disabled reduces SWB for nonreligious people more than that for religious people by 2.62 (p < 0.01). This study confirms that following a religion helps people cope with adverse circumstances such as the onset of a disability.

Keywords: Religion Disability Subjective well-being Happiness Difference-in-differences estimation

National identification (strength of association with the nation state in which an individual resides) predicts lower anxiety and improved health

Opium of the people? National identification predicts well‐being over time. Sammyh S. Khan et al. British Journal of Psychology, April 3 2019. https://doi.org/10.1111/bjop.12398

Abstract: Social group membership and its social‐relational corollaries, for example, social contact, trust, and support, are prophylactic for health. Research has tended to focus on how direct social interactions between members of small‐scale groups (i.e., a local sports team or community group) are conducive to positive health outcomes. The current study provides evidence from a longitudinal cross‐cultural sample (N = 6,748; 18 countries/societies) that the prophylactic effect of group membership is not isolated to small‐scale groups, and that members of groups do not have to directly interact, or in fact know of each other to benefit from membership. Our longitudinal analyses suggest that national identification (strength of association with the nation state in which an individual resides) predicts lower anxiety and improved health; national identification was in fact almost as positively predictive of health status as anxiety was negatively predictive. The findings indicate that identification with large‐scale groups, like small‐scale groups, is palliative, and are discussed in terms of globalization and banal nationalism.

As economic profits grow larger, so do economic losses at the other end of the distribution; the vast majority of the world’s largest companies (the middle 60 pct of the power curve), record near-zero economic profit, on average

What every CEO needs to know about ‘superstar’ companies. Sree Ramaswamy, Michael Birshan, James Manyika, Jacques Bughin, and Jonathan Woetzel. McKinsey Global Institute, April 2019. https://www.mckinsey.com/featured-insights/innovation-and-growth/what-every-ceo-needs-to-know-about-superstar-companies

The superstar effect is real

The distribution of economic profit along the power curve has gotten more skewed over the past 20 years. After adjusting for inflation, today’s superstar companies have 1.6 times more economic profit, on average, than the superstar companies of 20 years ago. It is not just economic profit that qualifies these companies as superstars: they are among the world’s most sought-after employers, most valuable brands, and most valuable equity listings.

As economic profits grow larger, so do economic losses at the other end of the distribution. The bottom 10 percent of companies destroy as much value as the top 10 percent create, and today’s bottom-decile companies have 1.5 times more economic loss, on average, than their counterparts of 20 years ago (Exhibit 1). That means for every company that creates economic value, there is another company that destroys economic value. Yet these value-destroying companies continue to survive, holding on to their resources for increasingly longer durations and continuing to attract capital. A growing number are turning into “zombie” companies (June 2017: https://www.oecd-ilibrary.org/economics/the-walking-dead_180d80ad-en), unable to generate enough cash flow even to sustain interest payments on their debts. The impact of these economic losses goes beyond these companies’ investors, managers, and workers: it drives down the returns for healthy companies that compete for the same resources or profits.

For the vast majority of the world’s largest companies, those making up the middle 60 percent of the power curve, economic profit is hard to retain. They record near-zero economic profit, on average. For these companies, market forces are powerful constraints on creating and retaining value, forcing them to compete away whatever advantages they may have in the marketplace. For the average company, the skew of economic profit means that it becomes relatively more painful to be in the middle of the pack, and strategy becomes even more relevant.

The bottom 10 percent of companies destroy as much value as the top 10 percent create, and today’s bottom-decile companies have 1.5 times more economic loss, on average, than their counterparts of 20 years ago (Exhibit 1). That means for every company that creates economic value, there is another company that destroys economic value. Yet these value-destroying companies continue to survive, holding on to their resources for increasingly longer durations and continuing to attract capital. A growing number are turning into “zombie” companies (June 2017: https://www.oecd-ilibrary.org/economics/the-walking-dead_180d80ad-en), unable to generate enough cash flow even to sustain interest payments on their debts. The impact of these economic losses goes beyond these companies’ investors, managers, and workers: it drives down the returns for healthy companies that compete for the same resources or profits.

Unraveling the asymmetry of Mona Lisa smile?

Unraveling the asymmetry of Mona Lisa smile. Luca Marsili, Lucia Ricciardi, Matteo Bologna. Cortex, April 3 2019, https://doi.org/10.1016/j.cortex.2019.03.020

Abstract: The Mona Lisa portrait, by Leonardo da Vinci, is one of the most famous paintings in the world. Over the years, there have been a number of debated topics on the painting, including the valence of the emotion expressed on her face. Nevertheless, the most recent interpretations agree that Mona Lisa expression is happiness. The smile asymmetry of Mona Lisa is another remarkable feature of the painting. We here asked forty-two healthy raters to judge which of the six basic emotions (or neutral expression) was expressed by the chimeric images of the left or right lower hemi face. We collected chosen responses, confidence levels and reaction times. Our results indicate that happiness is expressed only on the left side. According to some influent theories of emotion neuropsychology, we here interpreted the Mona Lisa asymmetric smile as a non-genuine smile, also thought to occur when the subject lies. Given that Leonardo was a great observer of human physiognomy we speculate on the intriguing possibility that Leonardo already knew the true meaning of asymmetric smile. Thus, Mona Lisa asymmetric smile could represent a stratagem Leonardo deliberately used to hold cryptic and enigmatic messages. Although the Mona Lisa smile continues to attract the attention of its observers, the true message it conveys remains elusive and many unsolved mysteries remain to be elucidated, perhaps via the knowledge of emotion neuropsychology.

Majority of hormesis research has not been privately funded: The public sector (federal & state governmental agencies) exclusively contributed to 78% of the reported research funding

Funding trends in hormetic research. MA Cottrell, WA Mills2 and EJ Calabrese. Human and Experimental Toxicology, Apr 1 2019. https://doi.org/10.1177/0960327119836224

Abstract: The topic of hormesis research funding has been a focus of deliberation within the scientific community for several decades. A common assumption/belief is that most hormesis research is funded by the private sector. With this assumption may emerge questions revolving around potential bias of such research. To provide some clarification to this issue, all hormesis research articles were obtained through online databases for 5-year increments starting with 1995 and ending with 2015 and were subsequently categorized by their funding source. A total of 710 articles were found for those years and 383 of those reported information on funding sources. Reporting funding is not required by law and until more recently was not encouraged or required by funders, research institutions, and/or scientific publishers. The analysis revealed that the assumption that the majority of hormesis research has been privately funded was not supported, with the public sector (i.e. federal and state governmental agencies) exclusively contributing to 78% of the reported research funding. Going forward, funding transparency for scientific research as a whole is essential within the scientific community as it may affect how research may be perceived, accepted, and applied.

Keywords: Hormesis, hormetic, funding sources, bias, risk assessment, dose–response.

A person's abortion views in 1982 led many to switch parties over time; individuals realigned their party affiliation in accordance with their initial abortion views, & their other political, economic and social views followed suit

Party hacks and true believers: The effect of party affiliation on political preferences. Eric D. Gould, Esteban F. Klor. Journal of Comparative Economics, Mar 25 2019. https://doi.org/10.1016/j.jce.2019.03.004

Highlights
•    We study the effect of party affiliation on an individual's political views.
•    We show that a person's abortion views in 1982 led many to switch parties over time as parties diverged in their stances on this issue.
•    As individuals realigned their party affiliation in accordance with their initial abortion views, their other political, economic and social views followed suit.

Abstract: This paper examines the effect of party affiliation on an individual's political views. To do this, we exploit the party realignment that occurred in the U.S. due to abortion becoming a more prominent and highly partisan issue over time. We show that abortion was not a highly partisan issue in 1982, but a person's abortion views in 1982 led many to switch parties over time as the two main parties diverged in their stances on this issue. We find that voting for a given political party in 1996, due to the individual's initial views on abortion in 1982, has a substantial effect on a person's political, social, and economic attitudes in 1997. These findings are stronger for highly partisan political issues, and are robust to controlling for a host of personal views and characteristics in 1982 and 1997. As individuals realigned their party affiliation in accordance with their initial abortion views, their other political views followed suit.

The threat of punishment lowered the average quality & quantity of information processed, compared with the prospect of reward or no performance incentive; also induced less cautious decision making by lowering decision thresholds

Information Processing Under Reward Versus Under Punishment. Timothy Ballard et al. Psychological Science, April 2, 2019. https://doi.org/10.1177/0956797619835462

Abstract: Much is known about the effects of reward and punishment on behavior, yet little research has considered how these incentives influence the information-processing dynamics that underlie decision making. We fitted the linear ballistic accumulator to data from a perceptual-judgment task to examine the impacts of reward- and punishment-based incentives on three distinct components of information processing: the quality of the information processed, the quantity of that information, and the decision threshold. The threat of punishment lowered the average quality and quantity of information processed, compared with the prospect of reward or no performance incentive at all. The threat of punishment also induced less cautious decision making by lowering people’s decision thresholds relative to the prospect of reward. These findings suggest that information-processing dynamics are determined not only by objective properties of the decision environment but also by the higher order goals of the system.

Keywords: information processing, reward, punishment, decision making, computational modeling, open data

Sugar Rush or Sugar Crash? A Meta-Analysis of Carbohydrate Effects on Mood: Do not have a beneficial effect on any aspect of mood, lowers alertness within 60 minutes after consumption, increase fatigue within 30 min post-consumption

Sugar Rush or Sugar Crash? A Meta-Analysis of Carbohydrate Effects on Mood. Konstantinos Mantantzis, Friederike Schlaghecken, Sandra I.Sünram-Lea, Elizabeth A.Maylor. Neuroscience & Biobehavioral Reviews, Apr 3 2019. https://doi.org/10.1016/j.neubiorev.2019.03.016

Highlights
•    Carbohydrates do not have a beneficial effect on any aspect of mood.
•    Carbohydrate consumption lowers alertness within 60 minutes after consumption.
•    Carbohydrates increase fatigue within 30 minutes post-consumption.

Abstract: The effect of carbohydrate (CHO) consumption on mood is much debated, with researchers reporting both mood improvements and decrements following CHO ingestion. As global consumption of sugar-sweetened products has sharply increased in recent years, examining the validity of claims of an association between CHOs and mood is of high importance. We conducted a systematic review and meta-analysis to evaluate the relationship between acute CHO ingestion and mood. We examined the time-course of CHO-mood interactions and considered the role of moderator variables potentially affecting the CHO-mood relationship. Analysis of 176 effect sizes (31 studies, 1259 participants) revealed no positive effect of CHOs on any aspect of mood at any time-point following their consumption. However, CHO administration was associated with higher levels of fatigue and less alertness compared with placebo within the first hour post-ingestion. These findings challenge the idea that CHOs can improve mood, and might be used to increase the public's awareness that the ‘sugar rush’ is a myth, inform health policies to decrease sugar consumption, and promote healthier alternatives.