Monday, August 13, 2018

Early life deprivation promotes the development of strategies that minimize the downside costs of uncertainty across domains, which results in greater risk-aversion, present-orientation, & prosociality; these effects need not be dependent on salient cues to mortality

An uncertainty management perspective on long-run impacts of adversity: The influence of childhood socioeconomic status on risk, time, and social preferences. Dorsa Amir, Matthew R. Jordan, David G. Rand. Journal of Experimental Social Psychology, Volume 79, November 2018, Pages 217-226. https://doi.org/10.1016/j.jesp.2018.07.014

Abstract: While there has been a recent increase in focus on the role of early life socioeconomic status (SES) on preferences and decision-making, there is still debate surrounding the proper theoretical framework for understanding such effects. Some have argued that early life SES can fundamentally shift time preferences per se, such that those from low SES backgrounds favor current rewards over future rewards. Others have argued that, while early life SES has lasting effects on behavior, such effects are only observable in the presence of salient cues to mortality. Here, we propose an alternative framework that centers on environmental uncertainty. In this uncertainty management framework, early life deprivation promotes the development of strategies that minimize the downside costs of uncertainty across domains. We argue that this focus on managing uncertainty results in greater risk-aversion, present-orientation, and prosociality. Furthermore, these effects need not be dependent on salient cues to mortality. Across four large samples of participants (total N = 4714), we find that childhood deprivation uniquely predicts greater risk-aversion (both incentivized and hypothetical) and greater prosociality in economic games. Childhood deprivation also predicts greater present-orientation, but not above-and beyond current SES. We further find that mortality cues are not necessary to elicit these differences. Our results support an uncertainty management perspective on the effects of childhood SES on risk, time, and social preferences.

Women are attracted to men who display heroism and altruism, this preference is higher when the male is attractive compared to unattractive, and preferences for prosocial traits were higher when seeking a long-term compared to a short-term partner

Margana, Lacey, Manpal S. Bhogal, James E. Bartlett, and Daniel Farrelly. 2018. “Exploring Altruism and Heroism: The Effects of Physical Attraction in Female Mate Choice.” PsyArXiv. August 13. doi:10.31234/osf.io/kgpv

Abstract: The role of prosocial behaviour in female mate choice has been extensively explored, focusing on the desirability of altruism in potential mates, as well as altruism being a mating signal. However, little research has focused on the desirability of heroism and altruism in potential partners. Furthermore, the synergistic effect of attractiveness on the desirability of prosocial traits has only recently been explored, and to our knowledge, has not explored in relation to the desirability of heroism in a romantic partner. We explored the effect of prosociality and attractiveness on female desirability ratings (n=198), and whether desirability was influenced by whether women were seeking a short-term or long-term relationship. We find that women are attracted to men who display heroism and altruism, and this preference is higher when the male is attractive compared to unattractive. Furthermore, preferences for prosocial traits were higher when seeking a long-term compared to a short-term partner. Our findings add to the literature on prosocial behaviour and mate choice.

Phaesants: Apparently ‘poor’ cognitive performance (slow reversal speed suggesting low behavioural flexibility) correlates with fitness benefits in at least some circumstances, implying a novel mechanism by which continued exaggeration of cognitive abilities may be constrained

The quick are the dead: pheasants that are slow to reverse a learned association survive for longer in the wild. Joah R. Madden, Ellis J. G. Langley, Mark A. Whiteside, Christine E. Beardsworth, Jayden O. van Horik. Philosophical Transactions of the Royal Society B: Biological Sciences, September 26 2018, Volume 373, issue 1756. http://rstb.royalsocietypublishing.org/content/373/1756/20170297

Abstract: Cognitive abilities probably evolve through natural selection if they provide individuals with fitness benefits. A growing number of studies demonstrate a positive relationship between performance in psychometric tasks and (proxy) measures of fitness. We assayed the performance of 154 common pheasant (Phasianus colchicus) chicks on tests of acquisition and reversal learning, using a different set of chicks and different set of cue types (spatial location and colour) in each of two years and then followed their fates after release into the wild. Across all birds, individuals that were slow to reverse previously learned associations were more likely to survive to four months old. For heavy birds, individuals that rapidly acquired an association had improved survival to four months, whereas for light birds, slow acquirers were more likely to be alive. Slow reversers also exhibited less exploratory behaviour in assays when five weeks old. Fast acquirers visited more artificial feeders after release. In contrast to most other studies, we showed that apparently ‘poor’ cognitive performance (slow reversal speed suggesting low behavioural flexibility) correlates with fitness benefits in at least some circumstances. This correlation suggests a novel mechanism by which continued exaggeration of cognitive abilities may be constrained.

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1. Introduction

One powerful approach to understand how natural selection may act on cognition is to measure the performance of individuals in a particular cognitive domain, and then explore how their performance correlates with a (proxy) fitness measure [1,2]. This is achieved by deploying explicit psychometric tasks targeting specific, defined cognitive processes [3,4]. Because fitness itself is hard to measure [5], researchers tend to use proxies that are presumed to correspond to reproductive success and/or survival. This correlational approach has predominantly revealed a positive relationship between an individual's performance in the psychometric task and a (proxy) measure of their fitness. Ants Lasius niger that exhibited faster route learning had greater colony-level foraging success [6]. Male African striped mice (Rhabdomys pumilio) that escaped quickly from mazes also had increased probability of surviving to the breeding season [7]. Male guppies (Poecilia reticulata) that learned mazes quickly were preferred by females [8]. Male bitterling (Rhodeus ocellatus) (practising a ‘sneaker’ strategy) that exhibited better maze learning subsequently had higher reproductive success [9]. Male song sparrows (Melospiza melodia) that demonstrated better control in a detour-reaching task had a larger song repertoire [10]. Male starlings (Sturnus vulgaris) with better spatial learning exhibited longer song bouts [11]. One study of female Australian magpies (Cracticus tibicen dorsalis) reported a link between their reproductive success and a general factor summarizing their performance in a battery of four tasks [12]. By contrast, a study of spotted bowerbirds (Ptilonorhynchus maculatus) found no relationship between a male's mating success and his performance in a battery of six tasks, either individually or when his performance was summarized by a single component [13]. Only one study has reported a negative relationship: male song sparrows that were fast at spatial learning also had smaller song repertoires [14]. This implies that natural selection generally leads to more exaggerated cognitive performance and associated abilities.

Interpretation of these previous studies is complicated by three factors. First, in all cases except one [12], a single assay has been used for each cognitive process being investigated. Reliance on a single assay risks a misattribution of the mechanisms driving individual performance. For example, learning to discriminate between two colour cues may indicate the specific ability or inherent motivation to prefer one colour over another [3], rather than the more general ability to learn associatively. A more robust method would be to use two (or more) tests that assay the same putative cognitive mechanism but differ in format or cue uses and hence triangulate on the outcome (Volter et al. [15]). We considered two ubiquitous cognitive processes and tested each using two different test variants. Associative learning involves learning to associate a stimulus with a reward and may be tested using a binary discrimination. Reversal learning may be measured by the speed at which such a previously learned association can be reversed. Reversal learning is considered to indicate an individual's ability to exert executive, inhibitory control and thus be behaviourally flexible ([16,17] corvids (Gymnorhinus cyanocephalus, Nucifraga columbiana, Aphelocoma californica); but see also [18] humans). The processes have been linked to specific behaviours and fitness consequences. Associative learning performance determines adult foraging strategies ([19] sparrow, Passer domesticus) and rapid learning speeds enhance individual's foraging or reproductive success ([20,21] grasshopper, Schistocerca americana; wasp, Biosteres arisanus). Flexibility permits rapid switching between different optimal decisions in changeable environments [22] so that more behaviourally flexible individuals have improved invasion success ([23] Birds) or a better ability to track fluctuating social groups ([24] Primates). The two processes (associative learning and reversal learning) may be closely related to one another. In several other species, speeds of associative learning and reversal learning are negatively related ([25–27] myna, chickadee, scrub-jay (Aphelocoma coerulescens), red junglefowl (Gallus gallus)). However, this negative relationship is not inevitable ([13,28] bowerbird, robin (Petroica longipes)) and indeed may be positive [29] or moderated by another factor e.g. testosterone [25].

Second, previous studies have not attempted to explicitly test how performance in abstract cognitive tasks relates to specific behaviours upon which selection may act. For example, it is not clear how improved inhibitory control as revealed by performance in a detour task may relate to song-learning processes [10], or how the ability to navigate a maze manifests in improved mating success [9]. One possibility is that cognitive performances and natural behaviours are linked by an overarching personality, such that an individual's behaviour in one context (a cognitive task) is linked to their behaviour in another context [30,31]. Alternatively, a cognitive ability has an immediate link to a natural behaviour, independent of personality. For example, performance in maze learning may correspond to the methods by which an individual learns to navigate their environment and recall feeding and refuge locations. By explicitly testing how cognitive abilities relate to broader personality assays, or more specific behaviours likely to relate to fitness outcomes, we can better understand how selection may act on these abilities.

Finally, studies have either had to test wild individuals for whom prior experience, social ranking and/or age is unknown, or they have relied on laboratory systems where the putative fitness consequences are hard to relate to the natural world. Administering controlled psychometric tests to wild animals, in which a large, random and reasonably complete sample of individuals participate over a large number of repeated presentations is problematic [1–4]. One solution is to capture animals from the wild and take them into captivity where they can be tested before release back into the wild. This approach encounters two problems. First, capture may not be random [32], so that the sample tested is not representative of the wild population. Second, individuals may have undergone different prior experiences that could lead to biases or preferences (e.g. for a particular colour) developed in other contexts that skew their performance in tests [3]. Such problems may be overcome by testing captive-reared individuals where prior experiences can be controlled and participation ensured. However, captive animals are not subject to natural selective pressures because predators are excluded and resources are provided in excess, and hence robust and relevant fitness measures are difficult to collect. This may explain why previous studies have used proxy measures of fitness.

We made use of a unique study system, the common pheasant (Phasianus colchicus) (hereafter pheasants). In the UK, these birds can be reared in captivity from hatching and subsequently released into the wild (for hunting). This ensures that individuals all experience identical developmental trajectories and prior experiences, all can be tested under controlled conditions and, critically, after release can be subject to natural selective pressures in the wild, where their fates can be monitored. We reared pheasant chicks from hatching to 10 weeks under controlled conditions in 2014 and 2015, and during this time we could subject them to psychometric tests of acquisition and reversal learning [33]. We used two sets of tests of particular processes, specifically the acquisition and reversal of associations between cues and rewards, using two different task paradigms (one discriminating colours and the other discriminating spatial positions on the test apparatus), with one task paradigm used in each year, to improve our confidence that it was the cognitive process that we were measuring rather than simply response to one particular set of cues. Critically, we then released birds into the wild and followed their fates, using survival as an unambiguous indicator of their fitness. Pheasant survival may be affected by year [34,35], sex ([36,37], but see also [38]), mass ([39], but see also [40]) and interactions between them (e.g. [41]). Therefore, we considered these in conjunction with performances in the cognitive tests. Pheasant mortality is typically high, especially in early life when birds are first independent, due to both terrestrial and avian predators [41,42]. This mortality occurs when pheasants disperse from their open-topped release pens and hence encounter novel predators and move away from artificial food provision. Pheasants that leave such safe release sites and fail to learn new foraging locations or refuges from predators are likely to be highly susceptible. We asked whether survival was predicted by a pheasant's early life performance in psychometric tests of learning and reversal, controlling for other non-cognitive factors such as sex and mass. Given the ambiguous relationship previously reported between an individual's speed of acquisition and reversal [13,25–29], we tested how performances in these two tasks were related to each other in pheasants. We then explored two mechanisms by which any such relationships between cognition and fitness may be mediated by their movement and exploration. As pheasants moved further away from their point of release (in a protected and provisioned pen—see below), they would encounter higher densities of predators and lower densities of artificial food supplies, and hence face an increased risk of predation or starvation. First, we tested how an individual's exploratory behaviour in a series of assays under controlled conditions when five weeks old correlated with their cognitive ability. Second, we tested how early life cognitive performance related to adult ranging behaviour after release.
The quick are the dead: pheasants that are slow to reverse a learned association survive for longer in the wild. Joah R. Madden, Ellis J. G. Langley, Mark A. Whiteside, Christine E. Beardsworth, Jayden O. van Horik. Philosophical Transactions of the Royal Society B: Biological Sciences, September 26 2018, Volume 373, issue 1756. http://rstb.royalsocietypublishing.org/content/373/1756/20170297

Abstract: Cognitive abilities probably evolve through natural selection if they provide individuals with fitness benefits. A growing number of studies demonstrate a positive relationship between performance in psychometric tasks and (proxy) measures of fitness. We assayed the performance of 154 common pheasant (Phasianus colchicus) chicks on tests of acquisition and reversal learning, using a different set of chicks and different set of cue types (spatial location and colour) in each of two years and then followed their fates after release into the wild. Across all birds, individuals that were slow to reverse previously learned associations were more likely to survive to four months old. For heavy birds, individuals that rapidly acquired an association had improved survival to four months, whereas for light birds, slow acquirers were more likely to be alive. Slow reversers also exhibited less exploratory behaviour in assays when five weeks old. Fast acquirers visited more artificial feeders after release. In contrast to most other studies, we showed that apparently ‘poor’ cognitive performance (slow reversal speed suggesting low behavioural flexibility) correlates with fitness benefits in at least some circumstances. This correlation suggests a novel mechanism by which continued exaggeration of cognitive abilities may be constrained.

---
1. Introduction

One powerful approach to understand how natural selection may act on cognition is to measure the performance of individuals in a particular cognitive domain, and then explore how their performance correlates with a (proxy) fitness measure [1,2]. This is achieved by deploying explicit psychometric tasks targeting specific, defined cognitive processes [3,4]. Because fitness itself is hard to measure [5], researchers tend to use proxies that are presumed to correspond to reproductive success and/or survival. This correlational approach has predominantly revealed a positive relationship between an individual's performance in the psychometric task and a (proxy) measure of their fitness. Ants Lasius niger that exhibited faster route learning had greater colony-level foraging success [6]. Male African striped mice (Rhabdomys pumilio) that escaped quickly from mazes also had increased probability of surviving to the breeding season [7]. Male guppies (Poecilia reticulata) that learned mazes quickly were preferred by females [8]. Male bitterling (Rhodeus ocellatus) (practising a ‘sneaker’ strategy) that exhibited better maze learning subsequently had higher reproductive success [9]. Male song sparrows (Melospiza melodia) that demonstrated better control in a detour-reaching task had a larger song repertoire [10]. Male starlings (Sturnus vulgaris) with better spatial learning exhibited longer song bouts [11]. One study of female Australian magpies (Cracticus tibicen dorsalis) reported a link between their reproductive success and a general factor summarizing their performance in a battery of four tasks [12]. By contrast, a study of spotted bowerbirds (Ptilonorhynchus maculatus) found no relationship between a male's mating success and his performance in a battery of six tasks, either individually or when his performance was summarized by a single component [13]. Only one study has reported a negative relationship: male song sparrows that were fast at spatial learning also had smaller song repertoires [14]. This implies that natural selection generally leads to more exaggerated cognitive performance and associated abilities.

Interpretation of these previous studies is complicated by three factors. First, in all cases except one [12], a single assay has been used for each cognitive process being investigated. Reliance on a single assay risks a misattribution of the mechanisms driving individual performance. For example, learning to discriminate between two colour cues may indicate the specific ability or inherent motivation to prefer one colour over another [3], rather than the more general ability to learn associatively. A more robust method would be to use two (or more) tests that assay the same putative cognitive mechanism but differ in format or cue uses and hence triangulate on the outcome (Volter et al. [15]). We considered two ubiquitous cognitive processes and tested each using two different test variants. Associative learning involves learning to associate a stimulus with a reward and may be tested using a binary discrimination. Reversal learning may be measured by the speed at which such a previously learned association can be reversed. Reversal learning is considered to indicate an individual's ability to exert executive, inhibitory control and thus be behaviourally flexible ([16,17] corvids (Gymnorhinus cyanocephalus, Nucifraga columbiana, Aphelocoma californica); but see also [18] humans). The processes have been linked to specific behaviours and fitness consequences. Associative learning performance determines adult foraging strategies ([19] sparrow, Passer domesticus) and rapid learning speeds enhance individual's foraging or reproductive success ([20,21] grasshopper, Schistocerca americana; wasp, Biosteres arisanus). Flexibility permits rapid switching between different optimal decisions in changeable environments [22] so that more behaviourally flexible individuals have improved invasion success ([23] Birds) or a better ability to track fluctuating social groups ([24] Primates). The two processes (associative learning and reversal learning) may be closely related to one another. In several other species, speeds of associative learning and reversal learning are negatively related ([25–27] myna, chickadee, scrub-jay (Aphelocoma coerulescens), red junglefowl (Gallus gallus)). However, this negative relationship is not inevitable ([13,28] bowerbird, robin (Petroica longipes)) and indeed may be positive [29] or moderated by another factor e.g. testosterone [25].

Second, previous studies have not attempted to explicitly test how performance in abstract cognitive tasks relates to specific behaviours upon which selection may act. For example, it is not clear how improved inhibitory control as revealed by performance in a detour task may relate to song-learning processes [10], or how the ability to navigate a maze manifests in improved mating success [9]. One possibility is that cognitive performances and natural behaviours are linked by an overarching personality, such that an individual's behaviour in one context (a cognitive task) is linked to their behaviour in another context [30,31]. Alternatively, a cognitive ability has an immediate link to a natural behaviour, independent of personality. For example, performance in maze learning may correspond to the methods by which an individual learns to navigate their environment and recall feeding and refuge locations. By explicitly testing how cognitive abilities relate to broader personality assays, or more specific behaviours likely to relate to fitness outcomes, we can better understand how selection may act on these abilities.

Finally, studies have either had to test wild individuals for whom prior experience, social ranking and/or age is unknown, or they have relied on laboratory systems where the putative fitness consequences are hard to relate to the natural world. Administering controlled psychometric tests to wild animals, in which a large, random and reasonably complete sample of individuals participate over a large number of repeated presentations is problematic [1–4]. One solution is to capture animals from the wild and take them into captivity where they can be tested before release back into the wild. This approach encounters two problems. First, capture may not be random [32], so that the sample tested is not representative of the wild population. Second, individuals may have undergone different prior experiences that could lead to biases or preferences (e.g. for a particular colour) developed in other contexts that skew their performance in tests [3]. Such problems may be overcome by testing captive-reared individuals where prior experiences can be controlled and participation ensured. However, captive animals are not subject to natural selective pressures because predators are excluded and resources are provided in excess, and hence robust and relevant fitness measures are difficult to collect. This may explain why previous studies have used proxy measures of fitness.

We made use of a unique study system, the common pheasant (Phasianus colchicus) (hereafter pheasants). In the UK, these birds can be reared in captivity from hatching and subsequently released into the wild (for hunting). This ensures that individuals all experience identical developmental trajectories and prior experiences, all can be tested under controlled conditions and, critically, after release can be subject to natural selective pressures in the wild, where their fates can be monitored. We reared pheasant chicks from hatching to 10 weeks under controlled conditions in 2014 and 2015, and during this time we could subject them to psychometric tests of acquisition and reversal learning [33]. We used two sets of tests of particular processes, specifically the acquisition and reversal of associations between cues and rewards, using two different task paradigms (one discriminating colours and the other discriminating spatial positions on the test apparatus), with one task paradigm used in each year, to improve our confidence that it was the cognitive process that we were measuring rather than simply response to one particular set of cues. Critically, we then released birds into the wild and followed their fates, using survival as an unambiguous indicator of their fitness. Pheasant survival may be affected by year [34,35], sex ([36,37], but see also [38]), mass ([39], but see also [40]) and interactions between them (e.g. [41]). Therefore, we considered these in conjunction with performances in the cognitive tests. Pheasant mortality is typically high, especially in early life when birds are first independent, due to both terrestrial and avian predators [41,42]. This mortality occurs when pheasants disperse from their open-topped release pens and hence encounter novel predators and move away from artificial food provision. Pheasants that leave such safe release sites and fail to learn new foraging locations or refuges from predators are likely to be highly susceptible. We asked whether survival was predicted by a pheasant's early life performance in psychometric tests of learning and reversal, controlling for other non-cognitive factors such as sex and mass. Given the ambiguous relationship previously reported between an individual's speed of acquisition and reversal [13,25–29], we tested how performances in these two tasks were related to each other in pheasants. We then explored two mechanisms by which any such relationships between cognition and fitness may be mediated by their movement and exploration. As pheasants moved further away from their point of release (in a protected and provisioned pen—see below), they would encounter higher densities of predators and lower densities of artificial food supplies, and hence face an increased risk of predation or starvation. First, we tested how an individual's exploratory behaviour in a series of assays under controlled conditions when five weeks old correlated with their cognitive ability. Second, we tested how early life cognitive performance related to adult ranging behaviour after release.

Women: Exposure to thin models deteriorated body image while increasing body dissatisfaction and anxiety; conversely, exposure to overweight models improved body image and decreased body dissatisfaction but it did not affect anxiety

Images of Thin and Plus-Size Models Produce Opposite Effects on Women’s Body Image, Body Dissatisfaction, and Anxiety. Silvia Moreno-Domínguez et al. Sex Roles, https://link.springer.com/article/10.1007/s11199-018-0951-3

Abstract: Mainstream media’s promotion of dangerously thin female images likely lowers self-image satisfaction and contributes to pathological body concerns and disordered eating among women. We tested upward and downward social-comparison effects on self-evaluations by exposing 145 Spanish women to images of thin (upward) or overweight (downward) models. We also tested whether explicitly asking or not asking participants to compare themselves with the models would moderate social comparison effects. Exposure to thin models deteriorated body image while increasing body dissatisfaction and anxiety. Conversely, exposure to overweight models improved body image and decreased body dissatisfaction but it did not affect anxiety. Whether participants were asked to compare themselves to the models explicitly or implicitly had no effect on the participants’ responses. Furthermore, pre-existing body image concerns were not associated with the pre-to-post exposure effects. We propose that increasing the representation of normal weight and overweight women in media advertisements could help to neutralize or at least reduce the negative impact of media’s practice to idealize thin and overly thin women as symbols of female beauty.

Sunday, August 12, 2018

Grooming helps animals remove dirt, parasites and other contaminants from skin and hair & may positively influence the animals’ affective state; cows spend about fivefold more time grooming compared with when brushes are not available

Emilie McConnachie, Anne Marieke C. Smid, Alexander J. Thompson, Daniel M. Weary, Marek A. Gaworski, Marina A. G. von Keyserlingk: Cows are highly motivated to access a grooming substrate, Biology Letters (2018). DOI: 10.1098/rsbl.2018.0303

Abstract: In natural environments, cattle use trees and other abrasive surfaces to scratch and groom themselves. Modern indoor dairy cattle housing systems often lack appropriate grooming substrates, restricting the animals' ability to groom. We assessed the motivation of dairy cows to access an automated mechanical brush, a grooming resource that can be implemented in indoor cattle housing systems. Cows were trained to push a weighted gate to access either fresh feed (positive control), a mechanical brush or the same space without a brush (negative control). Weight on the gate was gradually increased until all cows failed to open it. The weight each cow was willing to push to access each resource was assessed using the Kaplan–Meier survival analysis. Despite differences in methodology used to obtain data on motivation to access feed and the brush, the outcomes were very similar; cows worked as hard for access to fresh feed and the brush (p = 0.94) and less hard for access to the empty space (compared with fresh feed: p < 0.01; brush: p < 0.02). These results indicate that cows are highly motivated to access a mechanical brush and that it is an important resource for cows.

Social behavior in mouse models of autism spectrum disorder normalized when investigators triggered the release of a specific signaling substance, serotonin, in a single part of the animals' brains

5-HT release in nucleus accumbens rescues social deficits in mouse autism model. Jessica J. Walsh, Daniel J. Christoffel, Boris D. Heifets, Gabriel A. Ben-Dor, Aslihan Selimbeyoglu, Lin W. Hung, Karl Deisseroth & Robert C. Malenka. Nature (2018), https://doi.org/10.1038/s41586-018-0416-4

Abstract: Dysfunction in prosocial interactions is a core symptom of autism spectrum disorder. However, the neural mechanisms that underlie sociability are poorly understood, limiting the rational development of therapies to treat social deficits. Here we show in mice that bidirectional modulation of the release of serotonin (5-HT) from dorsal raphe neurons in the nucleus accumbens bidirectionally modifies sociability. In a mouse model of a common genetic cause of autism spectrum disorder—a copy number variation on chromosome 16p11.2—genetic deletion of the syntenic region from 5-HT neurons induces deficits in social behaviour and decreases dorsal raphe 5-HT neuronal activity. These sociability deficits can be rescued by optogenetic activation of dorsal raphe 5-HT neurons, an effect requiring and mimicked by activation of 5-HT1b receptors in the nucleus accumbens. These results demonstrate an unexpected role for 5-HT action in the nucleus accumbens in social behaviours, and suggest that targeting this mechanism may prove therapeutically beneficial.

Gossip Drives Vicarious Learning and Facilitates Robust Social Connections

Jolly, Eshin, and Luke J. Chang. 2018. “Gossip Drives Vicarious Learning and Facilitates Robust Social Connections.” PsyArXiv. August 11. doi:10.31234/osf.io/qau5s

Abstract: Exchanging gossip is a ubiquitous and complex human behavior, yet its precise social function remains poorly understood. Prior work has focused on characterizing its role in increasing cooperation through social sanctioning. However, gossip has been theorized to have a more fundamental role in social life. Here we provide empirical evidence that gossip plays a critical role in vicarious learning and social bonding. First, we establish the conditions under which individuals spontaneously engage in gossip, and demonstrate that gossip promotes the rapid spread of information about others’ unobserved actions, which causally influences future behavior. Second, we demonstrate that gossip facilitates the formation of social connections between individuals. Conversants feel more positively towards each other relative to other individuals, influence each other’s future behavior, and align social impressions. These results directly contradict the commonly held view that gossip is primarily defamatory in nature, and instead demonstrate that gossip can provide a rich source of information to aid in navigating the social world that ultimately leads to more cooperative interactions by providing a mechanism to quickly forge social connections.

Check also: Individual differences in talking enjoyment: The roles of life history strategy and mate value. Shelia M. Kennison et al. Cogent Psychology, https://www.bipartisanalliance.com/2017/10/women-enjoy-talking-more-than-men.html

And: Gossip as an Intrasexual Competition Strategy: Sex Differences in Gossip Frequency, Content, and Attitudes. Adam C. Davis. Evolutionary Psychological Science, http://www.bipartisanalliance.com/2017/10/gossip-as-intrasexual-competition.html

And: What Shall We Talk about in Farsi? Content of Everyday Conversations in Iran. Mahdi Dahmardeh, R. I. M. Dunbar. Human Nature, http://www.bipartisanalliance.com/2017/08/content-of-everyday-conversations-in.html. Pay attention to the table there.

We designed a mobile video game to test spatial ability & tested more than 2.5 million people from every country; spatial ability of the population is correlated with country economic wealth, & gender inequality of a country is predictive of gender differences in navigation ability

Global Determinants of Navigation Ability. Antoine Coutrot et al. Current Biology, https://doi.org/10.1016/j.cub.2018.06.009

Highlights
•    We designed a mobile video game to test spatial ability in humans
•    We tested more than 2.5 million people from every country in the world
•    Spatial ability of the population of a country is correlated with economic wealth
•    Gender inequality of a country is predictive of gender differences in navigation ability

Summary: Human spatial ability is modulated by a number of factors, including age [1, 2, 3] and gender [4, 5]. Although a few studies showed that culture influences cognitive strategies [6, 7, 8, 9, 10, 11, 12, 13], the interaction between these factors has never been globally assessed as this requires testing millions of people of all ages across many different countries in the world. Since countries vary in their geographical and cultural properties, we predicted that these variations give rise to an organized spatial distribution of cognition at a planetary-wide scale. To test this hypothesis, we developed a mobile-app-based cognitive task, measuring non-verbal spatial navigation ability in more than 2.5 million people and sampling populations in every nation state. We focused on spatial navigation due to its universal requirement across cultures. Using a clustering approach, we find that navigation ability is clustered into five distinct, yet geographically related, groups of countries. Specifically, the economic wealth of a nation was predictive of the average navigation ability of its inhabitants, and gender inequality was predictive of the size of performance difference between males and females. Thus, cognitive abilities, at least for spatial navigation, are clustered according to economic wealth and gender inequalities globally, which has significant implications for cross-cultural studies and multi-center clinical trials using cognitive testing.

People are averse to machines making morally-relevant driving, legal, medical, and military decisions, and that this aversion is mediated by the perception that machines can neither fully think nor feel

People are averse to machines making moral decisions. Yochanan E. Bigman, Kurt Gray. Cognition, Volume 181, December 2018, Pages 21-34. https://doi.org/10.1016/j.cognition.2018.08.003

Abstract: Do people want autonomous machines making moral decisions? Nine studies suggest that that the answer is ‘no’—in part because machines lack a complete mind. Studies 1–6 find that people are averse to machines making morally-relevant driving, legal, medical, and military decisions, and that this aversion is mediated by the perception that machines can neither fully think nor feel. Studies 5–6 find that this aversion exists even when moral decisions have positive outcomes. Studies 7–9 briefly investigate three potential routes to increasing the acceptability of machine moral decision-making: limiting the machine to an advisory role (Study 7), increasing machines’ perceived experience (Study 8), and increasing machines’ perceived expertise (Study 9). Although some of these routes show promise, the aversion to machine moral decision-making is difficult to eliminate. This aversion may prove challenging for the integration of autonomous technology in moral domains including medicine, the law, the military, and self-driving vehicles.

Saturday, August 11, 2018

Women preferred stoic men who worked even though they were experiencing health problems as long-term mates, disregarding the male's facial symmetry and physique; in short-term mate choice, disregarded stoicism

Female Choice and Male Stoicism. Susan G. Brown, Susan Shirachi, and Danielle Zandbergen. Journal of Evolutionary Medicine, https://www.ashdin.com/abstract/female-choice-and-male-stoicism-3240.html

Abstract: Men consistently report that they are healthier than women but have higher mortality rates. We hypothesized that men were sexually selected to present themselves as healthy to possible mates, according to predictions from health selection theory. The present study tested this theory by contrasting known influences of female mate choice with male's reactions to a health problem (flu symptoms, reaction to vog (air pollution associated with volcanic emissions in the Hawaiian islands) or a headache). Participants viewed three sets of slides contrasting male facial symmetry, physique, and status with stoicism (defined as ignoring a health problem) and were asked to choose which male they preferred as a long-term or a short-term mate. Participants preferred stoic men who worked even though they were experiencing health problems as long-term mates, disregarding the male's facial symmetry and physique. Status also significantly affected long-term mate choice. In short-term mate choice, participants shifted their preferences to symmetrical faces and mesomorphic bodies, signals of attractiveness, disregarding stoicism. In conclusion, our data provide support for health selection theory. Additionally, preventive health measures directed at men should recognize their reluctance to recognize minor health problems and focus on techniques that enhance men's perception of their health symptoms.


Masturbation with a Tool by an Infant Male Chimpanzee

Masturbation with a Tool by an Infant Male Chimpanzee. Michio Nakamura. Graduate School of Science, Kyoto University, Japan. http://mahale.main.jp/PAN/2018/001.html

INTRODUCTION

Here I report a case of “masturbation” with a tool by a wild infant chimpanzee. More accurately, the infant male inserted his erect penis into a wadge discarded by an adult male and performed several thrusts, as if he was copulating with the wadge. The observed “masturbation” did not involve ejaculation, because infant chimpanzees are unable to ejaculate. A similar behavior, i.e., rubbing the penis against a piece of fruit (e.g., orange peel), was reported for infant male orangutans in captivity (Harrison 1962). There are also some reported cases of captive or rehabilitant orangutans and chimpanzees stimulating their own genitals with tools (Dixson 2012).

Masturbation, or self-stimulation of one’s own sexual organs, is common among humans and nowadays is regarded as useful for healthy sexual development (Kaestle & Allen 2011). Various nonhuman primates are also known to masturbate (Thomsen et al. 2003; Dixson 2012; Thomsen & Sommer 2015); therefore, it may be a phylogenetically ancient behavior. However, there are relatively few studies that focus on masturbation among nonhuman primates in the wild (Thomsen & Soltis 2004). Male chimpanzees (Pan troglodytes) are known to stimulate their own penises. Although Goodall (1989) noted that captive chimpanzees sometimes ejaculate by stimulating their own penises, it had not been observed to result in ejaculation in the wild conspecifics at Gombe. Similarly, at Mahale, it is common for males to “fumble with penis,” but without it culminating in ejaculation (Nishida et al. 1999). Such fumbling of penis is done usually by hand (and sometimes by foot), but, thus far, I have found no reports of such penile-stimulating behaviors with tools, at least in wild chimpanzee populations.

Sex and age preferences: Why is age so important in human mating?

Conroy-Beam, D., & Buss, D. M. (2018). Why is age so important in human mating? Evolved age preferences and their influences on multiple mating behaviors. Evolutionary Behavioral Sciences. Advance online publication. http://dx.doi.org/10.1037/ebs0000127

Abstract: Evolutionary theorizing suggests that chronological age, because it is so strongly linked with key reproductive qualities like fertility, should be an exceptionally consequential variable in mate selection. We review voluminous evidence for mate preferences for age and the substantial and varied behavioral sequelae of those preferences. These include (a) in actual marriage decisions, men choose younger wives, and women choose older husbands, on average in all of the dozens of cultures studied; (b) in personal advertisements, men and women seek partners consistent with their expressed age preferences; (c) chronological age determines number of “hits” received in online dating services; (d) the age of potential bride influences the amount of money spent on premarriage customs; (e) men’s mate retention effort, including commitment manipulation, resource provisioning, and intrasexual threats, is significantly predicted by the wife’s age; and (f) chronological age is an important sex-linked cause of divorce. The far-reaching ramifications of age also extend to (g) tactics of intrasexual competition, (h) predictors of mate value discrepancies, (i) victims of sex crimes, and (j) prostitution patterns. Finally, chronological age predicts (k) probability of remarriage, and (l) the age gap between grooms and brides upon remarriage. We synthesize evidence from diverse methods, across different cultures, and over time spans of centuries. Massive converging evidence provides a powerful, yet complex, understanding of the evolutionary importance of age in multiple mating outcomes over the human life span.

Thursday, August 9, 2018

Pakistan's pivot to coal: Plan to spend $35bn loan from China on new power stations looks set to continue under Khan

Pakistan’s pivot to coal to boost energy gets critics fired up. Kiran Stacey in Lahore July 31, 2018. Financial Times.
https://www.ft.com/content/5cd07544-7960-11e8-af48-190d103e32a4
Plan to spend $35bn loan from China on new power stations looks set to continue under Khan

Pakistan believes it may have found a way out of its long-term energy supply crisis, thanks largely to more than $35bn worth of loans provided by China under the $60bn China-Pakistan Economic Corridor (CPEC).

The country has experienced years of rolling blackouts that have left residents in the dark and stifled the country’s manufacturing industries.

But now it is investing in an energy technology that is fast going out of fashion in other parts of the region — coal.

Under the CPEC, Beijing is planning to spend at least $35bn building new power stations, which will be mainly coal-fired, using resources from coalfields at Thar, about 400km east of Karachi. The plans will mean building 9.5 gigawatts of new coal-fired capacity — a third of the total capacity the country has already built.

This is in stark contrast with India, which recently said it would not approve any more new coal power plants — not least because the unit price of solar power has dropped below that of coal.

The previous government has defended its energy policies. Shehbaz Sharif, head of the Pakistan Muslim League-Nawaz party, which lost power in last week’s election, told the Financial Times before the vote: “We have built 11,000 megawatts of additional capacity in the space of five years, compared with 18,000 over the previous 66 years.”

And the strategy looks set to continue under the new prime minister Imran Khan, head of the Pakistan Tehreek-e-Insaf party. Again speaking before the election, Mr Khan told the FT he backed using Thar coal to boost the country’s electricity supplies. “Thar coal is in a desert, it’s near the coast, and there are new technologies which now make it possible that you don’t damage the environment,” he said.

Defenders of Pakistan’s build-up of coal point out that the fuel currently accounts for a very small fraction of the country’s installed electricity capacity. In India, that figure is around 75 per cent.

They also say that with tariffs higher in Pakistan than in neighbouring countries, encouraging cheap electricity supply is essential to help develop exporting manufacturers. The average electricity tariff for industry is around $0.13 per kilowatt-hour, compared with $0.12 in India and $0.09 in Bangladesh.

Pakistan exported goods worth 8.2 per cent of its gross domestic product last year, according to the World Bank, compared with 15 per cent by Bangladesh and nearly 19 per cent by India.

“Manufacturers in India and Bangladesh get cheaper electricity than those in Pakistan do,” says Ehsan Malik, chief executive of the Pakistan Business Council. “This is particularly problematic for the garment industry, especially since all three countries make clothes at the lower end of the sector, where energy prices account for a higher proportion of costs.”

Others, however, warn that while solar prices are falling, Pakistan is building a series of large power stations that will not only pollute the environment but could also saddle the country with high debts and could even become stranded assets in the long run.

Fiza Farhan, an independent development consultant and a former director of Buksh Energy, a solar power company, says: “I have banged my head against walls for years trying to get the government to launch solar projects on mega scales.

“But it was impossible to get projects into the final stage — every time we would get to the financing stage, the government would revise the tariffs.”

Economists warn, meanwhile, that the stress in the electricity sector is likely to become worse in the near term.

With the country’s stocks of foreign currency reserves rapidly declining, experts expect the new government to approach the International Monetary Fund for a bailout within months. The terms of that bailout, they warn, could include renegotiating or cancelling some of the projects backed by China and raising electricity tariffs.

Mohammed Sohail, chief executive of Topline Securities, a Karachi-based investment advisory company, says: “This government will also have to reduce expenditure in a major way through unpopular measures.”

Association between physical exercise and mental health in 1·2 million individuals in the USA between 2011 and 2015: More exercise was not always better

Association between physical exercise and mental health in 1·2 million individuals in the USA between 2011 and 2015: a cross-sectional study. Sammi R Chekroud et al. The Lancet Psychiatry, August 08, 2018. DOI:https://doi.org/10.1016/S2215-0366(18)30227-X

Summary

Background: Exercise is known to be associated with reduced risk of all-cause mortality, cardiovascular disease, stroke, and diabetes, but its association with mental health remains unclear. We aimed to examine the association between exercise and mental health burden in a large sample, and to better understand the influence of exercise type, frequency, duration, and intensity.

Methods: In this cross-sectional study, we analysed data from 1 237 194 people aged 18 years or older in the USA from the 2011, 2013, and 2015 Centers for Disease Control and Prevention Behavioral Risk Factors Surveillance System survey. We compared the number of days of bad self-reported mental health between individuals who exercised and those who did not, using an exact non-parametric matching procedure to balance the two groups in terms of age, race, gender, marital status, income, education level, body-mass index category, self-reported physical health, and previous diagnosis of depression. We examined the effects of exercise type, duration, frequency, and intensity using regression methods adjusted for potential confounders, and did multiple sensitivity analyses.

Findings: in the comments section

Interpretation: In a large US sample, physical exercise was significantly and meaningfully associated with self-reported mental health burden in the past month. More exercise was not always better. Differences as a function of exercise were large relative to other demographic variables such as education and income. Specific types, durations, and frequencies of exercise might be more effective clinical targets than others for reducing mental health burden, and merit interventional study.

By 2050, stringent climate mitigation policy, if implemented evenly across all sectors & regions, would have a greater negative impact on global hunger & food consumption than the direct impacts of climate change due to indirect impacts on prices/supplies of agri commodities

Risk of increased food insecurity under stringent global climate change mitigation policy. Tomoko Hasegawa, Shinichiro Fujimori, Petr Havlík, Hugo Valin, Benjamin Leon Bodirsky, Jonathan C. Doelman, Thomas Fellmann, Page Kyle, Jason F. L. Koopman, Hermann Lotze-Campen, Daniel Mason-D’Croz, Yuki Ochi, Ignacio Pérez Domínguez, Elke Stehfest, Timothy B. Sulser, Andrzej Tabeau, Kiyoshi Takahashi, Jun’ya Takakura, Hans van Meijl, Willem-Jan van Zeist, Keith Wiebe & Peter Witzke . Nature Climate Change, volume 8, pages699–703 (2018), https://www.nature.com/articles/s41558-018-0230-x

Abstract: Food insecurity can be directly exacerbated by climate change due to crop-production-related impacts of warmer and drier conditions that are expected in important agricultural regions1,2,3. However, efforts to mitigate climate change through comprehensive, economy-wide GHG emissions reductions may also negatively affect food security, due to indirect impacts on prices and supplies of key agricultural commodities4,5,6. Here we conduct a multiple model assessment on the combined effects of climate change and climate mitigation efforts on agricultural commodity prices, dietary energy availability and the population at risk of hunger. A robust finding is that by 2050, stringent climate mitigation policy, if implemented evenly across all sectors and regions, would have a greater negative impact on global hunger and food consumption than the direct impacts of climate change. The negative impacts would be most prevalent in vulnerable, low-income regions such as sub-Saharan Africa and South Asia, where food security problems are already acute.

Testosterone & self-perceived mate value increased following a manipulated “victory” in a sporting competition & were associated with heightened sociosexuality, & increased expectations toward approaching attractive women

Tandem Androgenic and Psychological Shifts in Male Reproductive Effort Following a Manipulated “Win” or “Loss” in a Sporting Competition. Daniel P. Longman et al. Human Nature, https://link.springer.com/article/10.1007/s12110-018-9323-5

Abstract: Male-male competition is involved in inter- and intrasexual selection, with both endocrine and psychological factors presumably contributing to reproductive success in human males. We examined relationships among men’s naturally occurring testosterone, their self-perceived mate value (SPMV), self-esteem, sociosexuality, and expected likelihood of approaching attractive women versus situations leading to child involvement. We then monitored changes in these measures in male rowers (N = 38) from Cambridge, UK, following a manipulated “win” or “loss” as a result of an indoor rowing contest. Baseline results revealed that men with heightened testosterone and SPMV values typically had greater inclinations toward engaging in casual sexual relationships and a higher likelihood of approaching attractive women in a hypothetical social situation. As anticipated, both testosterone and SPMV increased following a manipulated “victory” and were associated with heightened sociosexuality, and increased expectations toward approaching attractive women versus individuals who would involve them in interacting with children after the race. SPMV and self-esteem appeared to mediate some of the effects of testosterone on post-race values. These findings are considered in the broader context of individual trade-offs between mating and parental effort and a model of the concurrent and dynamic androgenic and psychological influences contributing to male reproductive effort and success.

Strong negative effects are attributed to sex dolls both in public & academic debates; sparse research points to strong positive outcomes as well: sex dolls can provide a lot of sexual & emotional satisfaction, create feelings of comfort, peace & even love

Sex toys, sex dolls, sex robots: Our under-researched bed-fellows. N. Döring, S. Pöschl. Sexologies, Volume 27, Issue 3, July–September 2018, Pages e51-e55. https://doi.org/10.1016/j.sexol.2018.05.009

Summary: In the 21st century, sexual products such as sex toys, sex dolls and sex robots are openly marketed on the Internet. The online retailer Amazon alone provides literally thousands of sexual wellness products. The Internet has done with sexual products what it has already achieved with pornography: it has expanded and diversified the market, made sexual products more accessible and affordable, and thus normalized their use. Research, though, is lagging behind: in comparison to the large body of pornography studies, research on sexual products, their users, uses and outcomes is scarce. The present paper therefore reviews both the state of technological development and the state of research regarding sex toys, sex dolls and sex robots marketed on the Internet. For each of these three groups of sexual product, we first present the range of products available and then provide data on their users and use. Finally, outcomes of sexual product use are discussed based on theoretical assumptions, available data and selected user experiences. Operating within a Positive Sexuality Framework (Williams et al., 2015) and a Positive Technology Framework (Riva et al., 2012), both rooted in the Positive Psychology Approach (Seligman and Csikszentmihalyi, 2000), the paper argues that sexual products have the potential to improve sexual well-being in various populations. Health professionals working in the field of sexuality need to be well-informed about the ever-evolving market of more and more technologically advanced sexual products. It is their call to foster both, the health-related use of existing sexual products and health-related development of future sexual products.

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Strong negative effects are attributed to sex dolls both in public and academic debates: men who buy and use female or even child-like sex dolls could be led to objectify and abuse real women and children just as they do their dolls (Ray, 2016; Valverde, 2012). Men who accept their dolls as social companions could harm themselves by no longer seek-ing for a human partner. Even innocuous sex doll use could lead to problems for the owner due to stigmatization by family and friends, leading to embarrassment, social withdrawal and guilt (Knox et al., 2017; Ray, 2016). However, the sparse research points to strong positive outcomes as well: sex dolls can provide a lot of sexual and emotional satisfaction, create feelings of comfort, peace and even love, as doll-owners report in surveys and interviews (Ferguson, 2010; Valverde, 2012).

In doll-owner forums, there are a lot of nuanced discussions about the pros and cons of sex dolls. While some owners confirm the problem of social stigmatization, others tell success stories about coming out as a doll-owner to their friends and family and finding acceptance. While some feel anxious about falling in love or becoming over-attached to a doll at the cost of real human contact, others describe the doll as a therapeutic tool that helps them to overcome a traumatic breakup or to cope with seemingly inevitable social and sexual deprivation due to physical and/or mental impairment.

Wednesday, August 8, 2018

Linguistic Inquiry and Word Count Markers of Narcissism

Holtzman, Nicholas S., Allison M. Tackman, Albrecht Kuefner, Fenne große Deters, Mitja Back, Brent Donnellan, James W. Pennebaker, et al. 2018. “LIWC Markers of Narcissism: An Exploratory LIWC Analysis of 15 Samples.” PsyArXiv. August 8. doi:10.31234/osf.io/yvna6

Abstract: Narcissism is virtually unrelated to using first-person singular pronouns (Carey et al., [2015] Journal of Personality and Social Psychology, 109). The degree to which narcissism is linked to other aspects of language use, however, remains unclear. We conducted a multi-site, multi-measure, and dual-language project to identify potential linguistic markers of narcissism. We applied the Linguistic Inquiry and Word Count (LIWC) program to a large number of written and spoken texts across 15 samples (total N = 4,941). The strongest positive correlates of narcissism were: using words related to sports, second-person pronouns, and swear words. The strongest negative correlates of narcissism were: using anxiety/fear words, tentative words, and words related to sensory/perceptual processes. All effects were small (each |r| less than .10).

Participants lie significantly more in the random-draw task than in the real-effort task, leading to the conclusion lying about luck is intrinsically less costly than lying about performance

Lying about luck versus lying about performance. Agne Kajackaite. Journal of Economic Behavior & Organization, Volume 153, September 2018, Pages 194-199. https://doi.org/10.1016/j.jebo.2018.07.010

Highlights
•    I compare lying behavior in a real-effort task and a random-draw task.
•    Participants lie more in the random-draw task than in the real-effort task.
•    Lying about luck is intrinsically less costly than lying about performance.
•    More generally, the way outcomes are determined affects the decision to lie.

Abstract: I compare lying behavior in a real-effort task in which participants have control over outcomes and a task in which outcomes are determined by pure luck. Participants lie significantly more in the random-draw task than in the real-effort task, leading to the conclusion lying about luck is intrinsically less costly than lying about performance.

We study whether face-to-face group deliberation changes other-regarding preferences; social interactions do indeed change individuals’ preferences; specifically, individuals whose preferences are extremely egoistic and also unchanging tend to influence others the most

Social interactions and the influence of “extremists”. Crawford Donna Harris. Journal of Economic Behavior & Organization, Volume 153, September 2018, Pages 238-266.
https://doi.org/10.1016/j.jebo.2018.07.007

Highlights
•    We study whether face-to-face group deliberation changes other-regarding preferences, particularly when individuals have to make their decisions alone afterwards.
•    We use a structural choice-revealed preference approach to measure each individual’s other-regarding preferences in a modified dictator game.
•    We examine heterogeneity in preferences and changes in these preferences before and after group deliberation.
•    We find that social interactions do indeed change individual preferences, even after they have left the group. In particularly, preferences of individuals in the same group become more homogenous after interactions.
•    We also find that students are more susceptible to social influence of individuals with extremely selfish preference (the “extremists” in our title) compared to non-students.

Abstract: A large literature has shown evidence that people are influenced by others, especially in group interactions. However, little is known about whether such influence remains after they have left the group. Using a modified dictator game and a structural choice-revealed preference approach, we measure an individual’s preferences before and after face-to-face interactions in a small group and then examine whether a change in preferences is observed after subjects have left the group and have to make their decisions alone. We find that social interactions do indeed change individuals’ preferences. Specifically, individuals whose preferences are extremely egoistic and also unchanging tend to influence others the most. These “left extremists” are more likely to be male and these effects are more prevalent amongst student subjects than non-student.

Intersectional Escape: Older Women Elude Agentic Prescriptions More Than Older Men

Intersectional Escape: Older Women Elude Agentic Prescriptions More Than Older Men. Ashley E. Martin, Michael S. North, Katherine W. Phillips. Personality and Social Psychology Bulletin, https://doi.org/10.1177/0146167218784895

Abstract: Both older individuals and women are proscribed from engaging in power-related behaviors, with women proscribed from behaving agentically and older individuals expected to cede desirable resources through “Succession.” However, little is known about whether these overlapping agency prescriptions equally target men and women across the lifespan. In seven studies, we find that older men face the strongest prescriptions to behave less agentically and cede resources, whereas older women are comparatively spared. We show that agency prescriptions more strongly target older men, compared to older women (Studies 1a, 1b, 2) and their younger counterparts (Studies 3 and 4) and examine social and economic consequences for agentic behavior in political, economic, and academic domains. We also find that older men garner more extreme (i.e., polarized) reactions due to their greater perceived resource threat (Studies 4-6). We conclude by discussing theoretical implications for diversity research and practical considerations for accommodating the fast-aging population.

Keywords: gender, age, ageism, intersectionality, backlash

In Western societies, a substantial proportion of the adult population does not have an intimate partner. Why? Evidence from Reddit

Why Men Stay Single? Evidence from Reddit. Menelaos Apostolou. Evolutionary Psychological Science, https://link.springer.com/article/10.1007/s40806-018-0163-7

Abstract: In Western societies, a substantial proportion of the adult population does not have an intimate partner. The current paper puts forward an evolutionary theoretical framework, where people stay single for three main reasons, namely the mismatch between ancestral and modern conditions has resulted in several individuals lacking the adaptations necessary for attracting and retaining mates, individuals can increase their fitness by opting out of relationships, and individuals have constraints that prevent them from attracting a mate. The paper attempted to identify the reasons that drive men to be single and to investigate whether they were consistent with the proposed theoretical framework. More specifically, 13,429 responses from a recent Reddit thread were analyzed, and 6794 responses were coded and classified in 43 categories. Among the most frequent reasons that men indicated for being single included poor flirting skills, low self-confidence, poor looks, shyness, low effort, and bad experience from previous relationships.

High price, brand label, the use of invasive placebos & high placebo dose increase the expectations toward the beneficial effect of a placebo treatment, which in turn boost the placebo effect; neuroimaging let us peek at mechanisms underlying these effects

Are Blue Pills Better Than Green? How Treatment Features Modulate Placebo Effects. Karin Meissner, Klaus Linde. International Review of Neurobiology, https://doi.org/10.1016/bs.irn.2018.07.014

Abstract: Treatment-related expectations are important predictors for placebo effects in various medical conditions. They are formed by verbal and nonverbal cues during the administration of treatments, such as verbal suggestions, conscious and unconscious associations with previous treatments, characteristics of patients and health-care providers as well as perceptual characteristics of the treatment. This review provides an overview of studies that aimed to elucidate the impact of treatment characteristics on expectations and placebo effects. Results show that high price, brand label, the use of invasive placebos and high placebo dose increase the expectations toward the beneficial effect of a placebo treatment, which in turn boost the placebo effect. Neuroimaging studies provide first insights into the neurobiological mechanisms underlying these differential placebo effects.

Handedness predicts Conservative-Republican preference and eliminates relations of Big Five personality to political orientation using the 48 contiguous American states as analytical units

Handedness predicts Conservative-Republican preference and eliminates relations of Big Five personality to political orientation using the 48 contiguous American states as analytical units. Stewart J. H. McCann. Laterality: Asymmetries of Body, Brain and Cognition, https://doi.org/10.1080/1357650X.2018.1508214

ABSTRACT: The two present nomothetic studies focused on the period from 1996 to 2012 to determine relations between handedness and political orientation using the 48 contiguous American states as analytical units. The estimated percentage of left-handers in each state operationally defined handedness. A composite measure of Conservative-Republican preference was created from CBS/New York Times/Gallup polls of state resident conservatism and the percent in each state voting Republican in each presidential election from 1996 to 2012. Study 1 showed that state levels of left-handedness correlated to an extremely high degree with Conservative-Republican preference (r = −.80). As well, with common demographic differences between states reflected in socioeconomic status, White population percent, and urban population percent controlled through multiple regression, handedness still accounted for an additional 37.2% of the variance in Conservative-Republican preference. Study 2 found that each of the Big Five personality variables correlated significantly with handedness and with Conservative-Republican preference, but in the opposite direction. Furthermore, Study 2 demonstrated quite surprisingly that all Big Five personality relations to Conservative-Republican preference were eliminated when handedness was controlled in multiple regression equations. For all regression equations, the global Moran’s I test specifically developed for detecting residual spatial autocorrelation indicated no significant spatial autocorrelation.

KEYWORDS: Handedness, conservatism, Republican, states, Big Five

Tuesday, August 7, 2018

Higher levels of childhood intelligence predict increased support for economic conservatism in adulthood; this link was partially mediated by educational attainment & achieved social class/income

Higher levels of childhood intelligence predict increased support for economic conservatism in adulthood. Gary J.Lewis, Timothy C.Bates. Intelligence, Volume 70, September–October 2018, Pages 36-41. https://doi.org/10.1016/j.intell.2018.07.006

Highlights
•    Higher intelligence is associated with lower levels of social conservatism.
•    Does intelligence also predict economically conservative attitudes?
•    We addressed this question using two large, longitudinal UK based cohorts.
•    Childhood intelligence positively predicted economic conservatism in adulthood.
•    This link was partially mediated by educational attainment and achieved social class/income.

Abstract: A number of studies have reported that higher intelligence is associated with socially liberal attitudes. Less clear, however, is whether this link extends to economic attitudes, although there are indications that higher intelligence is associated with economically conservative attitudes. Here in two large, longitudinal UK cohorts (each N > 7100) we assessed whether childhood intelligence predicted adulthood economic attitudes. In both cohorts we saw that higher levels of childhood (age 10–11) intelligence were related to higher levels of economic conservatism in adulthood (age 30–33). These effects were robust to the inclusion of potential confounders (sex, parental social class, childhood conduct problems). Moreover, this pathway was at least partially mediated by educational attainment and achieved social class/income. These findings confirm the importance of intelligence as an important phenotype for understanding the origins of economic attitudes. Implications for self-interest and rational-interest theories are discussed.

Exploring the Impact of Personal and Partner Traits on Sexuality: Sexual Excitation, Sexual Inhibition, and Big Five Predict Sexual Function in Couples

Exploring the Impact of Personal and Partner Traits on Sexuality: Sexual Excitation, Sexual Inhibition, and Big Five Predict Sexual Function in Couples. Julia Velten, Julia Brailovskaia & Jürgen Margraf. The Journal of Sex Research, https://doi.org/10.1080/00224499.2018.1491521

Abstract: Sexual difficulties are common among women and men and are associated with various mental and physical health problems. Although psychological traits are known to impact sexual attitudes and behavior, sexuality- and personality-related traits have not been jointly investigated to assess their relevance for sexual functioning in couples. The aim of this study was to investigate how psychological traits of two partners influence women’s and men’s sexual function. Data from 964 couples, representative of the adult population in Germany, were analyzed. Sexual function was assessed with the Female Sexual Function Index (FSFI) and the International Index of Erectile Function (IIEF). Sexuality-related traits were measured with the Sexual Excitation/Sexual Inhibition Inventory for Women and Men (SESII-W/M). Personality was measured with self-report and partner-rating versions of the Big Five Inventory (BFI). Sexual excitation was a positive and sexual inhibition was a negative predictor of sexual function in both genders. Women whose partners were sexually inhibited reported lower sexual function. Conscientious individuals reported better sexual function. Women whose partners were more conscientious also had better sexual function. Assessing partner-related factors may be helpful to identify predisposing and maintaining factors of sexual dysfunctions, especially in women.

When consumers self-create a product, they appreciate it to a greater degree, are likely to consume it more mindfully, & experience greater domain-specific & general well-being; private self-consciousness strengthens the effect

The self-creation effect: making a product supports its mindful consumption and the consumer’s well-being. Johanna Brunneder, Utpal Dholakia. Marketing Letters, https://link.springer.com/article/10.1007/s11002-018-9465-6

Abstract: Popular cultural movements such as Slow Food and the Maker Movement emphasize product self-creation―personally creating products, then consuming them, as a core value. We present the first research to examine how product self-creation affects the individual’s consumption experience of such products and their well-being. Seven field and lab studies provide evidence that when consumers self-create a product, they appreciate it to a greater degree, are likely to consume it more mindfully, and experience greater domain-specific and general well-being. The individual’s private self-consciousness strengthens the effect. Self-creating products offers consumers with a practical, versatile, and personal interest-driven way to transcend their traditional role, to consume more consciously and sustainably, while concurrently enhancing the enjoyment of their consumption experience.

Children were taught how to deceive to win a game; these children deceived better than control children, & improved their executive function & theory of mind skills; claim it is the 1st experiment to show learning to deceive enhances cognitive skills in children

Learning to deceive has cognitive benefits. Xiao Pan Ding et al. Journal of Experimental Child Psychology, Volume 176, December 2018, Pages 26-38. https://doi.org/10.1016/j.jecp.2018.07.008

Highlights
•    Children played hide-and-seek game on four consecutive days.
•    Experimental children were taught how to deceive to win the game.
•    We found experimental children deceived better than control children.
•    Experimental children improved their executive function and theory of mind skills.
•    It is first to show learning to deceive enhances cognitive skills in children.

Abstract: Recent evolutionary, cultural, and economic theories have postulated strong connections between human sociality and complex cognition. One prediction derived from this work is that deception should confer cognitive benefits on children. The current research tests this possibility by examining whether learning to deceive during early childhood promotes more advanced theory of mind and executive function skills during a time when these skills are undergoing rapid development. A total of 42 children (Mage = 40.45 months; 22 boys and 20 girls) who showed no initial ability to deceive were randomly assigned to an experimental condition or a control condition. In both conditions, they played a hide-and-seek game against an adult opponent on 4 consecutive days, but only the children in the experimental condition were taught how to deceive the opponent in order to win the game. Unlike children in the control condition, children in the experimental condition significantly improved their executive function and theory of mind skills, providing the first evidence that learning to deceive causally enhances cognitive skills in young children.

Monday, August 6, 2018

Big gender differences in reported intensity of arousal associated with one’s own as compared to a partner’s body: males reported significantly stronger arousal whilst touching or looking at a partner’s body, whereas females rated it as more arousing for own body to be touched or looked at

Tsakiris, Manos, Lara Maister, Aikaterini Fotopoulou, and Oliver Turnbull. 2018. “The Erogenous Mirror: Intersubjective and Multisensory Maps of Sexual Arousal.” PsyArXiv. August 5. doi:10.31234/osf.io/zreku

Abstract: Several areas of the body, known as ‘erogenous zones’, are able to elicit sexual arousal in the absence of direct genital stimulation. Previous scientific investigations of these erogenous zones have been restricted to the effects of tactile stimulation of one’s own body. However, human sexual interactions are interpersonal and multimodal, involving mutual touching, and looking at each other’s bodies. Here, we take a novel interpersonal and multimodal approach with a large (N=613) questionnaire-based sample to characterise the self-reported intensity and distribution of erogenous zones, mapped both on one’s own body and on an imagined partner’s body in response to being touched but also being looked at. We revealed two key findings; first, we observed clear correspondences between individuals’ topographic distributions of erogenous zones on their own and their partners’ bodies, as well as between those reported to be elicited by tactile and visual stimulation, suggesting the presence of an erogenous mirroring across individual and sensory modalities. Second, strong gender differences were observed in the reported intensity of arousal associated with one’s own as compared to a partner’s body; males reported significantly stronger arousal whilst touching or looking at a partner’s body, whereas females rated it as more arousing for their own body to be touched or looked at. Therefore, the erogeneity of body parts is represented on a multimodal, somatotopic map, which can be activated similarly for both one’s own and the partner’s body, highlighting for the first time the interpersonal and multisensory organization of the erogenous body.

Participants consumed an average of 110 unique foods over 28 days; females consumed more unique foods than did males over most all eating occasions; participants were generally satisfied with the amount of variety they selected

Variety in the diets of free-living, food-secure adults. Lauren E. Wisdorf et al. Food Quality and Preference, https://doi.org/10.1016/j.foodqual.2018.08.005

Highlights
•    We determined the variety of foods consumed by free-living, food-secure individuals.
•    We examined how the amount of variety consumed affected satisfaction with variety.
•    Participants consumed an average of 110 unique foods over 28 days.
•    Females consumed more unique foods than did males over most all eating occasions.
•    Participants were generally satisfied with the amount of variety they selected.

Abstract: Nursing homes, school lunch programs, institutional cafeterias, and households often struggle with balancing the cost of adding more variety with what consumers need to be satisfied. But we were unaware of any studies examining what people consider satisfactory variety within and across meals, days, weeks, and months. Our objectives were first to determine the variety of foods consumed by free-living, food-secure individuals 25 years of age or older with Bachelor’s degrees and no food allergies or sensitivities, and second, to evaluate how the amount of variety consumed in their diets affected their satisfaction with variety.

Participants (n = 102, 50% male) maintained a 28-day online food diary with seven eating occasions: breakfast, morning snack, lunch, afternoon snack, early evening snack, dinner, and late evening snack. After completing each week, participants rated their satisfaction with the variety in their diets that week. We measured dietary variety both as a count of unique foods, and as a proportion of unique foods. We evaluated how dietary variety differed by gender and by eating occasions. The total number of foods consumed each week, the count of unique foods, and the proportion of unique foods were compared with ratings of satisfaction with variety.

Participants consumed an average of 110 unique foods over 28 days with higher counts of unique foods for dinner (46 items), followed by lunch (38 items), and then breakfast (21 items). The highest proportions of unique foods were consumed at dinner (0.60) and early evening snack (0.59). Females consumed higher counts of unique foods than did males over most eating occasions. None of our dietary variety measures predicted participants’ satisfaction with variety. Our food-secure, highly educated, and free-living participants provided themselves with the amount of variety they needed to feel generally satisfied.

Brain: Some proteins are surprisingly long lived & resist proteasome decay, leading in pathological cases to prion disorders such as Creutzfeldt-Jakob disease; how this works at molecular levels & relates to age-related cellular burden in neurons that never “rejuvenate” through cell division?

Chapter 3. Prahlad & Chikka: Aging and the brain. In The Wiley Handbook on the Aging Mind and Brain. https://doi.org/10.1002/9781118772034.ch3

This chapter reviews molecular and cellular aspects of aging in the context of the evolution of aging. What is the advantage to humankind of long living? Organismal aging as a postreproductive process is not under strong reproductive selection. Extensions of lifespan may even correlate with reduced reproduction. The oldest known person ever, Jeanne Calment, died at age 122 and had only one daughter. Hers is a prominent human example of a broader inverse relationship between longevity and fertility across species, whose foundations remain unclear. A central theme of aging is the molecular and cellular instability and the role of the brain in regulating these processes. Some proteins are surprisingly long lived and resist proteasome decay, leading in pathological cases to prion disorders such as Creutzfeldt-Jakob disease. The authors review how this works at molecular levels and relates to age-related cellular burden in neurons that never “rejuvenate” through cell division. Parabiosis, or sharing of blood circulation of two organisms of different age, is the best known example of how blood-born molecules can affect organism vitality and longevity, possibly through additional trophic factors in the brain. This chapter lays biological foundations for interpreting findings on the aging mind and brain covered throughout this book.

Social networks, social relationships, and their effects on the aging mind and brain

Chapter 2. Ashida & Schafer: Social networks, social relationships, and their effects on the aging mind and brain. In The Wiley Handbook on the Aging Mind and Brain. https://doi.org/10.1002/9781118772034.ch2

Summary: People, like cells in a person’s body, are parts of dynamic systems and a network of support. Ashida and Schafer explore how social interactions at various levels affect healthy aging, much as cells in a body depend on functions of other parts. Mechanistic details of how such social interactions affect mind and brain health remain unclear, and individual variations tend to buck trends, yet common themes of social dependency emerge. Evidence strongly supports that caregiver and care receiver form dyads driven, for better or worse, by interactive dynamics at multiple levels. Social networks and interactions benefit healthy aging, but few attempts have been made to measure these interactions and harness their potential for improving healthy mind and brain aging in a rapidly changing society––where family interactions are progressively replaced by distant social networks in cyberspace. The effects of these dynamic changes on healthy aging of an ever-increasing population of seniors ready and willing to maintain social engagement are critical areas to be explored.

During early adolescence, boys receiving school-based sex education had more immature sexual beliefs than those who had not; later this is corrected

Let Us Talk About Sexual Immaturity in Adolescence: Implications for School-Based Sex Education. Anneliese C. Bolland et al. Sexuality Research and Social Policy, https://link.springer.com/article/10.1007/s13178-018-0348-7

Abstract: While rates of sexual activity among adolescents have declined, they remain high among adolescents living in poverty. Risky sexual behaviors are often compounded, placing adolescents at greater risk for increased prevalence of sexual behaviors during later adolescence and other behaviors that may compromise later life chances. Sexual immaturity may influence sexual initiation and trajectories of sexual behavior. In the current study, using a growth curve framework, data from the Mobile Youth and Poverty Study are used to model how sexual immaturity develops across adolescence as a function of age, gender, and sex education. Results suggest that girls are less sexually immature than boys, regardless of exposure to school-based sex education. For girls, sexual immaturity trajectories were similar throughout adolescence. However, during early adolescence, boys receiving school-based sex education had more immature sexual beliefs than those who had not. By middle adolescence, these differences had disappeared, and by late adolescence, boys receiving sex education had more mature attitudes boys who had not. Our results suggest that school-based sex education curricula should take into consideration how sexual maturity is portrayed among adolescents, particularly those who live in impoverished communities.

Sunday, August 5, 2018

Symptom misinformation: Participants were provided with feedback for some symptoms (targets), misleadingly suggesting that a slight majority of their peers experienced these targets on a regular basis; symptom ratings went down for control but not for target symptoms

Merckelbach, H., Dalsklev, M., van Helvoort, D., Boskovic, I., & Otgaar, H. (2018). Symptom self-reports are susceptible to misinformation. Psychology of Consciousness: Theory, Research, and Practice, http://dx.doi.org/10.1037/cns0000159

Abstract: We examined whether self-reported symptoms are affected by explicit and implicit misinformation. In Experiment 1, undergraduates (N = 60) rated how often they experienced somatic and psychological symptoms. During a subsequent interview, they were exposed to misinformation about 2 of their ratings: One was inflated (upgraded misinformation), whereas another was deflated (downgraded misinformation). Close to 82% of the participants accepted the upward symptom misinformation, whereas 67% accepted the downward manipulation. Also, 27% confabulated reasons for upgraded symptom ratings, whereas 8% confabulated reasons for downgraded ratings. At a follow-up test, some days later, participants (n = 55) tended to escalate their symptom ratings in accordance with the upgraded misinformation. Such internalization was less clear for downgraded misinformation. There was no statistically significant relation between dissociativity and acceptance or internalization of symptom misinformation. In Experiment 2, a more subtle and implicit form of misinformation was employed. Undergraduates (N = 50) completed a checklist of symptoms and were provided with feedback for some symptoms (targets), misleadingly suggesting that a slight majority of their peers experienced these targets on a regular basis. Next, participants rated the checklist again. Overall, symptom ratings went down for control but not for target symptoms. Taken together, our results demonstrate that symptom reports are susceptible to misinformation. The systematic study of symptom misinformation may help to understand iatrogenic effects in psychotherapy.

The effects of color bands on zebra finch behavior, physiology, life history, and fitness: Common knowledge that is NON-REPRODUCIBLE

Irreproducible text‐book “knowledge”: The effects of color bands on zebra finch fitness. Daiping Wang. Wolfgang Forstmeier, Malika Ihle, Mehdi Khadraoui, Sofia Jerónimo, Katrin Martin, Bart Kempenaers. Evolution, https://doi.org/10.1111/evo.13459

Abstract: Many fields of science—including behavioral ecology—currently experience a heated debate about the extent to which publication bias against null findings results in a misrepresentative scientific literature. Here, we show a case of an extreme mismatch between strong positive support for an effect in the literature and a failure to detect this effect across multiple attempts at replication. For decades, researchers working with birds have individually marked their study species with colored leg bands. For the zebra finch Taeniopygia guttata, a model organism in behavioral ecology, many studies over the past 35 years have reported effects of bands of certain colors on male or female attractiveness and further on behavior, physiology, life history, and fitness. Only eight of 39 publications presented exclusively null findings. Here, we analyze the results of eight experiments in which we quantified the fitness of a total of 730 color‐banded individuals from four captive populations (two domesticated and two recently wild derived). This sample size exceeds the combined sample size of all 23 publications that clearly support the “color‐band effect” hypothesis. We found that band color explains no variance in either male or female fitness. We also found no heterogeneity in color‐band effects, arguing against both context and population specificity. Analysis of unpublished data from three other laboratories strengthens the generality of our null finding. Finally, a meta‐analysis of previously published results is indicative of selective reporting and suggests that the effect size approaches zero when sample size is large. We argue that our field—and science in general—would benefit from more effective means to counter confirmation bias and publication bias.

Saturday, August 4, 2018

Research has predominantly focused on the negative effects of adversity on health and well-being; but under certain circumstances, adversity may have the potential for positive outcomes, such as increased resilience and thriving (steeling effect)

A Salutogenic Perspective on Adverse Experiences. The Curvilinear Relationship of Adversity and Well-Being. Jan Höltge et al. European Journal of Health Psychology (2018), 25, pp. 53-69. https://doi.org/10.1027/2512-8442/a000011

Abstract. Research has predominantly focused on the negative effects of adversity on health and well-being. However, the salutogenic perspective suggests that adversity may not always be detrimental (Antonovsky, 1996). In fact, under certain circumstances, adversity may have the potential for positive outcomes, such as increased resilience and thriving (Carver, 1998; Rutter, 1987). The “steeling effect” suggests that past experiences of adversity may increase resistance to later adversities. It proposes that moderate adversity may facilitate more adaptive functioning than no adversity or high levels of adversity (Rutter, 2006, 2012). The relationship between adversity and health may be optimally assessed using curvilinear models, yet the majority of previous studies have examined linear associations (Masten & Cicchetti, 2016). It is therefore the aim of this review to determine whether moderate adversity is associated with more adaptive functioning when compared to no and high levels of adversity. Practical implications and future research are also discussed.

Keywords: systematic review, steeling effect, resilience, thriving, curvilinear

The Status Signals Paradox: When making new friends, people tend to think that displaying high-status markers will make them more attractive to others, but they are found to be less attractive

The Status Signals Paradox. Stephen M. Garcia, Kimberlee Weaver, Patricia Chen.Social Psychological and Personality Science, https://doi.org/10.1177/1948550618783712

Abstract: Making friends is critical to well-being. We also live in a society where the display of status is ubiquitous and billions of dollars are spent on high-status consumer goods. In the present analysis, we introduce the Status Signals Paradox: When making new friends, people tend to think that displaying high-status markers of themselves (e.g., a BMW, a Tag Heuer watch) will make them more attractive to others than neutral markers (e.g., a Honda, a generic brand watch); however, from the perspective of would-be friends, individuals who display high-status markers are found to be less attractive as new friends than those with neutral status markers. Six studies provide converging evidence of the status signals paradox.

Keywords: social comparison, presenter paradox, decision-making, naive realism

Peripheral Factors Affecting the Evaluation of Artworks: When described as created by famous artists, the works were liked more and judged more interesting & beautiful & participants (n = 309), all art nonexperts, also were willing to pay more to see the works

Peripheral Factors Affecting the Evaluation of Artworks. Stefano Mastandrea, William D. Crano. Empirical Studies of the Arts, https://doi.org/10.1177/0276237418790916

Abstract: The goal of the research was to determine whether artworks said to be created by famous artists were appreciated more than the same artworks attributed to nonfamous artists. Analysis indicated that the works attributed to famous artists were more appreciated than the identical works attributed to nonfamous artists: The works were liked more and judged more interesting and beautiful (all p values < .001). Participants (N = 309), all art nonexperts, also were willing to pay more to see the works if described as created by famous artists (p < .001); importantly, however, no differences were found in ratings of the works’ comprehensibility. This pattern of results suggests that judgmental variations were attributable to participants’ peripheral processing of factors not intrinsic to the work itself. Dual process models of attitudes, popular in social psychology, were invoked to provide a framework for understanding the findings.

Keywords: art, persuasion, liking, comprehension, peripheral judgment processes

Male Testosterone Does Not Adapt to the Partner's Menstrual Cycle

Ström JO, Ingberg E, Slezak JK, et al. Male Testosterone Does Not Adapt to the Partner's Menstrual Cycle. The Journal of Sexual Medicine, Volume 15, Issue 8, August 2018, Pages 1103-1110. https://doi.org/10.1016/j.jsxm.2018.06.003

Abstract

Background: It has not yet been established whether men in heterosexual relationships adapt their hormone levels to their female partner's menstrual cycle to allocate reproductive resources to the period when the female is actually fertile.

Aim: This prospective observational study tested the hypothesis that some males have peaks in testosterone or acne (a possible biomarker for androgen activity) near their partners' ovulation, whereas other males display the opposite pattern.

Methods: 48 couples supplied menstrual cycle data, male salivary samples, and a protocol of daily activities for 120 days. Daily saliva samples were analyzed for testosterone concentrations by enzyme-linked immunosorbent assay. The main hypothesis was tested by analyzing whether each individual male's testosterone/acne response to ovulation (either an increase or a decrease in comparison to the individual's average levels) was stable over time. To do this, we analyzed the Spearman correlation between individually normalized periovulatory testosterone and acne during the first half of the study versus the second half of the study.

Outcomes: Correlation between each male individual's periovulatory testosterone and acne patterns during the first half of the study versus the second half of the study.

Results: No predictability in the male individuals' testosterone (Spearman's rho = −0.018, P = .905) or acne (Spearman's rho = −0.036, P = .862) levels during ovulation was found.

Clinical translation: The study being “negative,” there is no obvious translational potential in the results.

Strengths and limitations: The main strength of this study lies in the excellent compliance of the study participants and the large number of sampling timepoints over several menstrual cycles, thereby allowing each male individual to be his own control subject. A limitation is that samples were only obtained in the morning; however, including later timepoints would have introduced a number of confounders and would also have hampered the study's feasibility.

Conclusions: The current results strongly indicate that male morning testosterone levels neither increase nor decrease in response to the partner's ovulation. This discordance to previous laboratory studies could indicate either that (i) the phenomenon of hormonal adaptation of men to women does not exist and earlier experimental studies should be questioned, (ii) that the phenomenon is short-lived/acute and wanes if the exposure is sustained, or (iii) that the male testosterone response may be directed toward other women than the partner.

Big fires in California are less frequent and area burnt is smaller since at least 1970

Different historical fire–climate patterns in California. Jon E. Keeley and Alexandra D. Syphard. International Journal of Wildland Fire 26(4) 253-268. https://doi.org/10.1071/WF16102

Abstract: The relationship between annual variation in area burned and seasonal temperatures and precipitation was investigated for the major climate divisions in California. Historical analyses showed marked differences in fires on montane and foothill landscapes. Based on roughly a century of data, there are five important lessons on fire–climate relationships in California: (1) seasonal variations in temperature appear to have had minimal influence on area burned in the lower elevation, mostly non-forested, landscapes; (2) temperature has been a significant factor in controlling fire activity in higher elevation montane forests, but this varied greatly with season – winter and autumn temperatures showed no significant effect, whereas spring and summer temperatures were important determinants of area burned; (3) current season precipitation has been a strong controller of fire activity in forests, with drier years resulting in greater area burned on most United States Forest Service (USFS) lands in the state, but the effect of current-year precipitation was decidedly less on lower elevation California Department of Forestry and Fire Protection lands; (4) in largely grass-dominated foothills and valleys the magnitude of prior-year rainfall was positively tied to area burned in the following year, and we hypothesise that this is tied to greater fuel volume in the year following high rainfall. In the southern part of the state this effect has become stronger in recent decades and this likely is due to accelerated type conversion from shrubland to grassland in the latter part of the 20th century; (5) the strongest fire–climate models were on USFS lands in the Sierra Nevada Mountains, and these explained 42–52% of the variation in area burned; however, the models changed over time, with winter and spring precipitation being the primary drivers in the first half of the 20th century, but replaced by spring and summer temperatures after 1960.

Additional keywords: area burned, chaparral, climate change, forests, grasslands, ignitions, seasonal temperatures.