Monday, October 9, 2017

Male aggressiveness as intrasexual contest competition in 78 societies

Carter T, Kushnick G. (2017) Male aggressiveness as intrasexual contest competition in 78 societies. PeerJ Preprints 5:e3331v1

Abstract: Sexual selection favors traits that increase mating and, thus, reproductive success. Some scholars have suggested that intrasexual selection driven by contest competition has shaped human male aggression. If this is the case, one testable hypothesis is that beliefs and behavior related to male aggression should be more prevalent in societies where the intensity and strength of sexual selection is higher, as measured by factors such as: (a) the presence and scope of polygyny; (b) the number of same-sex competitors relative to potential mates; and, (c) the amount of effort males have available to allocate to mating. Using mixed-effect linear regression models with data from 78 societies from the Standard Cross-Cultural Sample, we found mixed support for the hypothesis using individual variables related to male aggression, but strong support when using a composite measure of male ‘aggressiveness’. We ruled out some potential alternative explanations by controlling for spatial autocorrelation, and confounding variables such as political complexity and warfare.

Childhood Amnesia in Children -- Emotion and contextual coherence predicted memory retention

Peterson, C., Hallett, D. and Compton-Gillingham, C. (2017), Childhood Amnesia in Children: A Prospective Study Across Eight Years. Child Dev. doi:10.1111/cdev.12972

Abstract: This was a prospective study of earliest memories across 8 years for 37 children who were of age 4–9 years initially. In three interviews (initial and after 2 and 8 years) children provided their three earliest memories; those from earlier interviews that were not spontaneously provided later were cued. There was little consistency in the earliest memory or overlap across interviews in spontaneous memories. The youngest group also forgot over half their initial memories although few were forgotten by older children. For consistency of content, 25%–32% of information by former 6- to 9-year-olds was the same after 8 years, but < 10% provided by the youngest children was the same and 22% was contradictory. Emotion and contextual coherence predicted memory retention.

Female exogamy and gene pool diversification at the transition from the Final Neolithic to the Early Bronze Age in central Europe

Female exogamy and gene pool diversification at the transition from the Final Neolithic to the Early Bronze Age in central Europe. Corina Knipper et al. Proceedings of the National Academy of Sciences, September 19, 2017, vol. 114 no. 38, pp 10083-10088. doi: 10.1073/pnas.1706355114

Significance: Paleogenetic and isotope data from human remains shed new light on residential rules revealing patrilocality and high female mobility in European prehistory. We show the crucial role of this institution and its impact on the transformation of population compositions over several hundred years. Evidence for an epoch-transgressing maternal relationship between two individuals demonstrates long-debated population continuity from the central European Neolithic to the Bronze Age. We demonstrate that a simple notion of “migration” cannot explain the complex human mobility of third millennium BCE societies in Eurasia. On the contrary, it appears that part of what archaeologists understand as migration is the result of large-scale institutionalized and possibly sex- and age-related individual mobility.

Abstract: Human mobility has been vigorously debated as a key factor for the spread of bronze technology and profound changes in burial practices as well as material culture in central Europe at the transition from the Neolithic to the Bronze Age. However, the relevance of individual residential changes and their importance among specific age and sex groups are still poorly understood. Here, we present ancient DNA analysis, stable isotope data of oxygen, and radiogenic isotope ratios of strontium for 84 radiocarbon-dated skeletons from seven archaeological sites of the Late Neolithic Bell Beaker Complex and the Early Bronze Age from the Lech River valley in southern Bavaria, Germany. Complete mitochondrial genomes documented a diversification of maternal lineages over time. The isotope ratios disclosed the majority of the females to be nonlocal, while this is the case for only a few males and subadults. Most nonlocal females arrived in the study area as adults, but we do not detect their offspring among the sampled individuals. The striking patterns of patrilocality and female exogamy prevailed over at least 800 y between about 2500 and 1700 BC. The persisting residential rules and even a direct kinship relation across the transition from the Neolithic to the Bronze Age add to the archaeological evidence of continuing traditions from the Bell Beaker Complex to the Early Bronze Age. The results also attest to female mobility as a driving force for regional and supraregional communication and exchange at the dawn of the European metal ages.

Keywords: mtDNA, strontium, oxygen, kinship, human mobility

My commentary: The authors say: "Systematic individual movements are an important factor in third millennium BCE societies in Eurasia and force us to reexamine evidence of “migration” that may actually be the result of large-scale institutionalized and possibly sex- and age-related individual mobility."

I see at least two ways to have institutionalized women mobility: 1  buying the women from other tribes; or 2  the kidnapping of women from other human groups and their becoming forced wives or slaves (this is more difficult because the women are buried like the men, which is not likely that it will be done as frequently with slaves as with the male warriors/kidnappers).

The psychology of not wanting to know

Gigerenzer, G., & Garcia-Retamero, R. (2017). Cassandra’s regret: The psychology of not wanting to know. Psychological Review, 124(2), 179-196.

Abstract: Ignorance is generally pictured as an unwanted state of mind, and the act of willful ignorance may raise eyebrows. Yet people do not always want to know, demonstrating a lack of curiosity at odds with theories postulating a general need for certainty, ambiguity aversion, or the Bayesian principle of total evidence. We propose a regret theory of deliberate ignorance that covers both negative feelings that may arise from foreknowledge of negative events, such as death and divorce, and positive feelings of surprise and suspense that may arise from foreknowledge of positive events, such as knowing the sex of an unborn child. We conduct the first representative nationwide studies to estimate the prevalence and predictability of deliberate ignorance for a sample of 10 events. Its prevalence is high: Between 85% and 90% of people would not want to know about upcoming negative events, and 40% to 70% prefer to remain ignorant of positive events. Only 1% of participants consistently wanted to know. We also deduce and test several predictions from the regret theory: Individuals who prefer to remain ignorant are more risk averse and more frequently buy life and legal insurance. The theory also implies the time-to-event hypothesis, which states that for the regret-prone, deliberate ignorance is more likely the nearer the event approaches. We cross-validate these findings using 2 representative national quota samples in 2 European countries. In sum, we show that deliberate ignorance exists, is related to risk aversion, and can be explained as avoiding anticipatory regret.

My commentary: Above 86pct don't want to know when our partner will die or the cause. Nor about our death's time and cause. Nor whether our marriage will end in divorce.

Acute Physical Exercise in Humans Enhances Reconsolidation of Emotional Memories

Acute Physical Exercise in Humans Enhances Reconsolidation of Emotional Memories. Dharani Keyan and Richard Bryant. Psychoneuroendocrinology, Volume 86, December 2017, Pages 144-151.

•    Memory reconsolidation occurs during modification after activation of memory.
•    Acute bouts of exercise proximal to learning enhances subsequent memory.
•    Acute exercise after trauma memory reactivation strengthened trauma memory.
•    Exercise during trauma memory reactivation may prolong trauma memories.

Abstract: Increasing evidence suggests that when a memory is reactivated through retrieval, it becomes temporarily vulnerable to environmental or pharmacological manipulation, which can consequently update or strengthen the memory. Physical exercise has been shown to modulate the maintenance of fear memories in animals following memory reactivation. This study investigated the effect of intense exercise in modulating the reconsolidation of trauma memories. Fifty-four undergraduate students watched a trauma film depicting the aftermath of a highway car crash. Two days later, participants engaged in either (a) 20-25 minutes of incremental cycling following a memory reactivation induction (Reactivation/Exercise), (b) 20-25 minutes of mild cycling (Reactivation/No Exercise) following memory reactivation, or (c) 20-25 minutes of incremental cycling but no memory reactivation (No Reactivation/Exercise). Saliva samples were collected to index salivary amylase and cortisol at baseline and post activity. Participants completed memory questionnaires relating to declarative and intrusive memory recall two days after memory reactivation. Reactivation/Exercise participants recalled more central details of the trauma film relative to other participants. Increased cortisol predicted better total memory recall in the Reactivation/Exercise, but not in the other conditions. These findings suggest that intense exercise during the period of memory reactivation enhances subsequent trauma memory, and provides human evidence consistent with recent findings of exercise-induced fear reconsolidation in animals.

Metaphors can give life meaning

Metaphors can give life meaning. Matthew Baldwin, Mark Landau and Trevor Swanson. Self and Identity,

Abstract: Conceptual metaphor theory offers a perspective on how and when people find meaning in life. Whereas life's meaning can be difficult to grasp, metaphor compares life to a relatively more concrete and structured concept. Supporting this account, American adults (Study 1) and German undergraduates (Study 2) who framed life as a journey reported more meaning in life. The journey metaphor was particularly beneficial for individuals with low levels of perceived coherence in life (Study 2). Study 3 further explored this pattern of moderation: An accessible metaphor, compared to other life framings, benefited participants who lack a strong meaning framework. Study 4 focused on the mechanism behind metaphor's influence. Participants who imagined events from their life journey perceived stronger interrelatedness among those events as measured with an analog spatial organization task. Perceived interrelatedness in turn predicted meaning in life, particularly for individuals with a strong preference for well-structured knowledge. Finally, participants who applied their own metaphor to life expressed greater meaning (Study 5), especially those high in personal need for structure (Study 6). An internal meta-analysis of these findings provides cumulative evidence for metaphor's influence on perceived meaning in life and reveals moderating features of the individual.

Keywords: Meaning in life, conceptual metaphor, epistemic needs, the self, existential psychology, humanistic psychology

The secret to happiness: Feeling good or feeling right?

Tamir, M., Schwartz, S. H., Oishi, S., & Kim, M. Y. (2017). The secret to happiness: Feeling good or feeling right? Journal of Experimental Psychology: General, 146(10), 1448-1459.

Abstract: Which emotional experiences should people pursue to optimize happiness? According to traditional subjective well-being research, the more pleasant emotions we experience, the happier we are. According to Aristotle, the more we experience the emotions we want to experience, the happier we are. We tested both predictions in a cross-cultural sample of 2,324 participants from 8 countries around the world. We assessed experienced emotions, desired emotions, and indices of well-being and depressive symptoms. Across cultures, happier people were those who more often experienced emotions they wanted to experience, whether these were pleasant (e.g., love) or unpleasant (e.g., hatred). This pattern applied even to people who wanted to feel less pleasant or more unpleasant emotions than they actually felt. Controlling for differences in experienced and desired emotions left the pattern unchanged. These findings suggest that happiness involves experiencing emotions that feel right, whether they feel good or not.

My commentary: When people asked for death at the Roman circus, they felt very well doing something cruel. We do not need to wish well or be sweet to all others, we can perfectly well hate and at the same time we may feel something really close to happiness.

Individual-sport athletes were found to be more energetic and open than team-sport athletes

Associations between personality, sports participation and athletic success. A comparison of Big Five in sporting and non-sporting adults. Patrizia Steca, Dario Baretta, , Andrea Greco, Marco D'Addario, Dario Monzani. Personality and Individual Differences. Volume 121, 15 January 2018, Pages 176–183.

•    Big Five are associated with participation and success in sports.
•    Energy and agreeableness are related to sport participation.
•    Consciousness and emotional stability are associated with sport success.
•    Individual-sport athletes are more energetic and open than team-sport athletes.
•    ESEM has been used to test for factor invariance and mean differences.

Abstract: The present study investigates whether the Big Five personality traits are different among diverse sports populations. A sample of 881 male athletes and non-athletes completed a self-report questionnaire measuring their personality traits. The Exploratory Structure Equation Modeling (ESEM) approach is adopted to test measurement invariance and mean differences among groups. The results indicate that athletes who had experienced the most success in their sport scored higher than non-athletes in each personality dimension of the Big Five, with the exception of openness, while less successful athletes scored higher than non-athletes only in extraversion and agreeableness. The more successful athletes showed higher agreeableness, conscientiousness, and emotional stability than the less successful athletes. Individual-sport athletes were found to be more energetic and open than team-sport athletes. The current findings help clarify the relationships between personality traits, sports participation and athletic success.

Keywords: Big Five personality factors; Exploratory structural equation modeling; Sport participation; Sport success; Individual and team sport

How Do Hunter-Gatherer Children Learn Subsistence Skills?

How Do Hunter-Gatherer Children Learn Subsistence Skills? A Meta-Ethnographic Review. Sheina Lew-Levy et al. Human Nature,

Abstract: Hunting and gathering is, evolutionarily, the defining subsistence strategy of our species. Studying how children learn foraging skills can, therefore, provide us with key data to test theories about the evolution of human life history, cognition, and social behavior. Modern foragers, with their vast cultural and environmental diversity, have mostly been studied individually. However, cross-cultural studies allow us to extrapolate forager-wide trends in how, when, and from whom hunter-gatherer children learn their subsistence skills. We perform a meta-ethnography, which allows us to systematically extract, summarize, and compare both quantitative and qualitative literature. We found 58 publications focusing on learning subsistence skills. Learning begins early in infancy, when parents take children on foraging expeditions and give them toy versions of tools. In early and middle childhood, children transition into the multi-age playgroup, where they learn skills through play, observation, and participation. By the end of middle childhood, most children are proficient food collectors. However, it is not until adolescence that adults (not necessarily parents) begin directly teaching children complex skills such as hunting and complex tool manufacture. Adolescents seek to learn innovations from adults, but they themselves do not innovate. These findings support predictive models that find social learning should occur before individual learning. Furthermore, these results show that teaching does indeed exist in hunter-gatherer societies. And, finally, though children are competent foragers by late childhood, learning to extract more complex resources, such as hunting large game, takes a lifetime.

Those that spent walking more than one h/day had a significantly lower risk of dementia than those than walked less than 0.5 h/d

Changes in time spent walking and the risk of incident dementia in older Japanese people: the Ohsaki Cohort 2006 Study. Yasutake Tomata Shu Zhang Kemmyo Sugiyama Yu Kaiho Yumi Sugawara Ichiro Tsuji. Age and Ageing, Volume 46, Issue 5, September 1 2017, Pages 857–860,

The impact of long-term changes in physical activity during adulthood in the context of primary prevention of dementia has not been addressed previously.

Objective: To study the relationship between changes in time spent walking after middle age and incident dementia in older Japanese individuals.

[Methodology and results in the comments section.]

Conclusions: These results suggest that maintaining a higher level of physical activity after middle age may be a key strategy for prevention of dementia in older age.

Keywords: walking, physical activity, dementia, older people, cohort study

ABB robot hatches 30 per cent more eggs for Singapore egg farm

ABB robot hatches 30 per cent more eggs for Singapore egg farm. By Mai Tao.
Robotics and Automation News, Oct 8 2017
Growing demand for locally-farmed eggs prompted Seng Choon Farm, to turn to automation in an effort to increase its production capacity

In April this year, ABB installed and commissioned a robotic palletizing system at Seng Choon Farm’s 36 acre site in north-west Singapore, to support increased production output as well as the company’s future expansion plans.

Since then, the robotic palletizing system, that stacks heavy boxes and baskets of eggs onto pallets, has raised the farm’s productivity by 30 per cent.

Before the robotic system was installed, workers would manually stack the cartons and baskets of eggs onto the pallets, with a single worker lifting about 15 tons of eggs a day.

This role was rotated among seven workers throughout the week to minimize safety risks that could arise due to the high intensity of the job.

The automated palletizing system now relieves these workers from lifting the heavy loads during their shift and has enabled the farm to re-deploy them in less strenuous roles.

 Ang Boon Hua, head of robotics, ABB Singapore, says: “While the nation expands its agriculture industry, it is highly essential that automation is adopted in all new developments to ensure sustainability.

“Robotic automation is an example of a dependable solution to reduce footprint on the factory floor and ensure continuation and optimization of production.

“We are pleased to contribute to the productivity of a trusted, home-grown brand such as Seng Choon Farm and will continue to support agricultural development in Singapore through our advanced technologies.”

With the robotic palletizing system now allowing the farm to lift 20 tonnes of eggs a day, raising productivity by 30 per cent, the farm foresees a further boost in output over the next few years.

Koh Yeow Koon, managing director of Seng Choon Farm, says: “The farm’s production volume has already risen from 150 million eggs per annum previously to exceed 200 million eggs per annum.

“I am convinced that the full productivity gains derived from ABB’s robotic technology will be further realized as we increase our production volume in the near future.”

While Seng Choon Farm aims to increase production volume through expanding its farmland and rearing more hens, its production capacity is very much dependent on capacity down the production line.

Koh says: “Running a farm involves feeding chickens, clearing manure, collecting, inspecting and sorting thousands of eggs a day, and packing them into trays, boxes, and finally pallets before they can be sent out.

“Automation at every stage of production is essential in order to handle the high production volume.”

Seng Choon Farm’s implementation of the palletizing system is supported under Capability Development Grant managed by Spring Singapore – an agency of the Ministry of Trade and Industry – that helps Singapore enterprises grow.

The local statutory agriculture and food authority announced earlier this year that 36 plots of new agricultural land for farming are being made available from August 2017 onwards, in an effort to ensure the nation’s food supply resilience.