Saturday, September 16, 2017

Local mating markets in humans and non-human animals

Local mating markets in humans and non-human animals. Ronald Noë. Behavioral Ecology and Sociobiology, October 2017, 71:148.

Abstract: In biology, the term ‘mating market’ has been fashionable for a few decades only, but sexual selection theory was implicitly based on economic principles from the start. I regard mating individuals explicitly as traders on markets and distinguish ‘global mating markets’, consisting of all reproducing members of a population, from ‘local mating markets’ (LMMs) that are disconnected in space and/or time. I focus on ways in which individuals make the best of variation among LMMs by adapting their mating strategy to each local market they enter. The ‘operational sex ratio’ (OSR; Emlen ST, Oring LW (1977) Science 197:215–223) gives a first approximation of the balance of power between the two trader classes: males and females ready to reproduce. The parameter I use is the local OSR (LOSR), the OSR of a single LMM. The balance of power is dependent not only on the LOSR, however, but also on the production costs and exchange values of ‘crucial commodities’, which often vary locally and over time. Distinguishing LMMs is most useful for species with strong variation in the LOSR. Human mating markets distorted by war, selective abortion and sex-biased migration are among the best-documented local markets with aberrant OSRs. Traders on LMMs may strategically adjust to supply and demand ratios and changes in their own market value but also attempt to change local market conditions or transfer to another local market with better conditions. Fine-tuning can result not only from conditional strategies, evolved under natural and sexual selection, but also from learning processes as far as species-specific cognitive constraints allow.

Significance statement: Biological market theory (BMT), which deals with cooperation among unrelated agents in general, is combined with sexual selection theory (SST), which deals with reproductive cooperation, to focus on an aspect that received little attention in the vast SST literature: adaptations that improve mating success when the market value of an individual varies considerably from one local mating market (LMM) to the next. An individual’s market value on an LMM is determined not only by the local operational sex ratio (LOSR) but also by the value of the goods and services that both sexes invest in their mates and/or the communal offspring. Case studies of both humans and non-human animals are used to illustrate the difference between global and local markets and to evaluate predictions based on the LMM-hypothesis.

Prediction 2: sensitivity to one’s own market value and adjustment to changes in market value of self and others

...Broadly speaking, individual changes inmarket value can be due to changes relative to local competitors, changes in the LOSR, or changes in the production costs of commodities. As the consequences of the latter are hard to predict, I will concentrate on the other two factors, the first of which is notably well documented in humans. ***A universal, frequently reported human pattern is that men are attracted by youth in women and women are attracted by men that can offer resources***... During their exceptionally long mating career, men can gradually gain in value with age by slowly accumulating wealth or a steady rise in salary. Their market value can also increase abruptly, for example by high gains in the lottery, or a sudden ascent to a powerful position. ***After reaching maximal fertility in their early twenties (Hawkes and Smith 2010), women tend to gradually lose market value, as far as this is contingent on their age. Men are sensitive to cues informing about age, which is ultimately linked to reproductive potential***. Humans of either sex tend to adjust their demands and expectations to changes in their market value. For example, following earlier papers... in both methods and ideas, Pawłowski and Dunbar... showed that ***with increasing age, women become less demanding, quantified as the number of preferred characteristics listed in ‘Lonely Hearts’ advertisements. This sensitivity to market value of self in humans has since been confirmed in numerous other studies...  Climbing down a peg when one is not doing very well on the mating market, often is a ‘best-of-a-bad-job’ strategy***... Inferior competitors in several species use strategies radically different from those of their high-quality rivals. ***For example, big bullfrogs croak loudly in order to attract females, but small males of the same species remain silent and ambush the females that are on their way to the big bullies, a strategy known as ‘sneaking’...  Strategies that differ radically from the main stream exist among humanmales too, of course, e.g. rape and brothel visits.***

Members of several other species are also able to calibrate their mate preferences according to their own market value.  Spotted bowerbird males decorate their bowers with Solanum berries, the number of which shows considerable variation among males with higher numbers correlating with higher mating success. After experimental changes of the number of berries that decorated their bower, males added or removed berries to such an extent that the natural number was more or less restored. Males with berry-numbers considerably larger than what they had contributed themselves, suffered an increased risk of having their bowers disrupted by neighbouring males. - (Griggio and Hoi 2010). The latter authors also found indications of sensitivity to the own attractivity in bearded reedlings... Another house sparrow study (Schwagmeyer 2014) showed similar market effects, not only during pair formation at the start of the reproductive season but also in the form of partner switches during the season. ***The latter reminds of humans again: people report more satisfaction with their present partner when their prospects of switching to a higher quality mate are dim...***

Check also: Behavioral display of lumbar curvature in response to the opposite sex. Zeynep Şenveli Bilkent University, Graduate Program in Neuroscience - Master's degree thesis.

And: The Reversed Gender Gap in Education and Assortative Mating in Europe. De Hauw, Yolien, Grow, Andre, and Van Bavel, Jan. European Journal of Population,

And: Marzoli, D., Havlícek, J. and Roberts, S. C. (2017), Human mating strategies: from past causes to present consequences. WIREs Cognitive Science, e1456. doi:10.1002/wcs.1456

And: The Causes and Consequences of Women’s Competitive Beautification. Danielle J. DelPriore, Marjorie L. Prokosch, and Sarah E. Hill. The Oxford Handbook of Women and Competition, edited by Maryanne L. Fisher.

Understanding what makes terrorist groups’ propaganda effective: an integrative complexity analysis of ISIL and al Qaeda

Understanding what makes terrorist groups’ propaganda effective: an integrative complexity analysis of ISIL and Al Qaeda. Shannon C. Houck, Meredith A. Repke & Lucian Gideon Conway III. Journal of Policing, Intelligence and Counter Terrorism, Vol. 12, issue 2, Pages 105-118.

ABSTRACT: The Islamic State of Iraq and the Levant (ISIL) became an increasingly powerful terrorist organisation in a relatively short period of time, drawing more recruits than its former affiliate, Al Qaeda. Many have attributed ISIL’s successful expansion in part to its extensive propaganda platform. But what causes terrorist groups to be effective in their communication to the public? To investigate, we examined one aspect of terrorists’ rhetoric: Integrative complexity. In particular, this historical examination provides a broad integrative complexity analysis of public statements released by key members of ISIL and Al Qaeda over a 10-year period when ISIL was rapidly growing as a terrorist entity (2004–2014). Findings revealed that (a) ISIL demonstrated less complexity overall than Al Qaeda (p < .001) and (b) ISIL became increasingly less complex over this focal time period (p < .001), while Al Qaeda’s complexity remained comparatively stable (p = .69). Taken together, these data suggest that as ISIL grew in size and strength between 2004 and 2014 – surpassing Al Qaeda on multiple domains such as recruitment, monetary resources, territorial control, and arms power – it simultaneously became less complex in its communication to the public.

KEYWORDS: Terrorism, propaganda, integrative complexity, ISIL, Al Qaeda


Myths and truths about the cellular composition of the human brain: A review of influential concepts. Christopher S.Bvon Bartheld. Journal of Chemical Neuroanatomy,

•    The myth of a 10:1 glia-neuron ratio in human brains has been debunked.
•    The myth of one trillion glial cells in human brains has been debunked.
•    The number of cortical neurons does not decline significantly in normal aging.
•    All counting methods benefit from calibration and validation.
•    Proof is needed for altered cell numbers in neurological and psychiatric disorders.

Abstract: Over the last 50 years, quantitative methodology has made important contributions to our understanding of the cellular composition of the human brain. Not all of the concepts that emerged from quantitative studies have turned out to be true. Here, I examine the history and current status of some of the most influential notions. This includes claims of how many cells compose the human brain, and how different cell types contribute and in what ratios. Additional concepts entail whether we lose significant numbers of neurons with normal aging, whether chronic alcohol abuse contributes to cortical neuron loss, whether there are significant differences in the quantitative composition of cerebral cortex between male and female brains, whether superior intelligence in humans correlates with larger numbers of brain cells, and whether there are secular (generational) changes in neuron number. Do changes in cell number or changes in ratios of cell types accompany certain diseases, and should all counting methods, even the theoretically unbiased ones, be validated and calibrated? I here examine the origin and the current status of major influential concepts, and I review the evidence and arguments that have led to either confirmation or refutation of such concepts. I discuss the circumstances, assumptions and mindsets that perpetuated erroneous views, and the types of technological advances that have, in some cases, challenged longstanding ideas. I will acknowledge the roles of key proponents of influential concepts in the sometimes convoluted path towards recognition of the true cellular composition of the human brain.

Abbreviations: CNScentral nervous system
GNR glia-neuron ratio
IF isotropic fractionator


Political Fact-Checking on Twitter: When Do Corrections Have an Effect? Drew Margolin, Aniko Hannak and Ingmar Weber. Political Communication,

Abstract: Research suggests that fact checking corrections have only a limited impact on the spread of false rumors. However, research has not considered that fact-checking may be socially contingent, meaning there are social contexts in which truth may be more or less preferred. In particular, we argue that strong social connections between fact-checkers and rumor spreaders encourage the latter to prefer sharing accurate information, making them more likely to accept corrections. We test this argument on real corrections made on Twitter between January 2012 and April 2014. As hypothesized, we find that individuals who follow and are followed by the people who correct them are significantly more likely to accept the correction than individuals confronted by strangers. We then replicate our findings on new data drawn from November 2015 to February, 2016. These findings suggest that the underlying social structure is an important factor in the correction of misinformation.

Keywords: accountability, fact-checking, misinformation, rumor, social networks

Land plants have regulated their stomatal conductance to allow their intrinsic water use efficiency to increase in nearly constant proportion to the rise in atmospheric [CO2]

Atmospheric evidence for a global secular increase in carbon isotopic discrimination of land photosynthesis. Ralph F. Keeling et al. Proceedings of the National Academy of Sciences,

Significance: Climate change and rising CO2 are altering the behavior of land plants in ways that influence how much biomass they produce relative to how much water they need for growth. This study shows that it is possible to detect changes occurring in plants using long-term measurements of the isotopic composition of atmospheric CO2. These measurements imply that plants have globally increased their water use efficiency at the leaf level in proportion to the rise in atmospheric CO2 over the past few decades. While the full implications remain to be explored, the results help to quantify the extent to which the biosphere has become less constrained by water stress globally.

Abstract: A decrease in the 13C/12C ratio of atmospheric CO2 has been documented by direct observations since 1978 and from ice core measurements since the industrial revolution. This decrease, known as the 13C-Suess effect, is driven primarily by the input of fossil fuel-derived CO2 but is also sensitive to land and ocean carbon cycling and uptake. Using updated records, we show that no plausible combination of sources and sinks of CO2 from fossil fuel, land, and oceans can explain the observed 13C-Suess effect unless an increase has occurred in the 13C/12C isotopic discrimination of land photosynthesis. A trend toward greater discrimination under higher CO2 levels is broadly consistent with tree ring studies over the past century, with field and chamber experiments, and with geological records of C3 plants at times of altered atmospheric CO2, but increasing discrimination has not previously been included in studies of long-term atmospheric 13C/12C measurements. We further show that the inferred discrimination increase of 0.014 ± 0.007‰ ppm−1 is largely explained by photorespiratory and mesophyll effects. This result implies that, at the global scale, land plants have regulated their stomatal conductance so as to allow the CO2 partial pressure within stomatal cavities and their intrinsic water use efficiency to increase in nearly constant proportion to the rise in atmospheric CO2 concentration.

A semantic space analysis of how presidential candidates and their supporters represent abstract political concepts differently

Speaking two "Languages" in America: A semantic space analysis of how presidential candidates and their supporters represent abstract political concepts differently. Ping Li, Benjamin Schloss and  Jake Follmer. Behavior Research Methods,

Abstract: In this article we report a computational semantic analysis of the presidential candidates' speeches in the two major political parties in the USA. In Study One, we modeled the political semantic spaces as a function of party, candidate, and time of election, and findings revealed patterns of differences in the semantic representation of key political concepts and the changing landscapes in which the presidential candidates align or misalign with their parties in terms of the representation and organization of politically central concepts. Our models further showed that the 2016 US presidential nominees had distinct conceptual representations from those of previous election years, and these patterns did not necessarily align with their respective political parties' average representation of the key political concepts. In Study Two, structural equation modeling demonstrated that reported political engagement among voters differentially predicted reported likelihoods of voting for Clinton versus Trump in the 2016 presidential election. Study Three indicated that Republicans and Democrats showed distinct, systematic word association patterns for the same concepts/terms, which could be reliably distinguished using machine learning methods. These studies suggest that given an individual's political beliefs, we can make reliable predictions about how they understand words, and given how an individual understands those same words, we can also predict an individual's political beliefs. Our study provides a bridge between semantic space models and abstract representations of political concepts on the one hand, and the representations of political concepts and citizens' voting behavior on the other.

Attitudes toward science seem to become ever more polarized

Attitudes Towards Science. Bastiaan T. Rutjens et al. Advances in Experimental Social Psychology,

Abstract: As science continues to progress, attitudes toward science seem to become ever more polarized. Whereas some put their faith in science, others routinely reject and dismiss scientific evidence. This chapter provides an integration of recent research on how people evaluate science. We organize our chapter along three research topics that are most relevant to this goal: ideology, motivation, and morality. We review the relations of political and religious ideologies to science attitudes, discuss the psychological functions and motivational underpinnings of belief in science, and describe work looking at the role of morality when evaluating science and scientists. In the final part of the chapter, we apply what we know about science evaluations to the current crisis of faith in science and the open science movement. Here, we also take into account the increased accessibility and popularization of science and the (perceived) relations between science and industry.

Keywords: Science; Belief in science; Antiscience; Motivation; Ideology; Religion; Morality; Control; Order; Existential meaning; Popularization of science; Open science

Tax compliance is greater for women than men, but men are more willing to contribute to public goods

The Role of Gender in the Provision of Public Goods through Tax Compliance. David M. Bruner, John D'Attoma, Sven Steinmo. Journal of Behavioral and Experimental Economics,

•    The results of a large scale laboratory tax compliance experiment conducted in the U.S., the U.K., Sweden, and Italy with nearly 5000 subjects are reported.
•    We find significant evidence of gender differences in tax compliance and the willingness to contribute to public goods.
•    We find robust evidence that tax compliance is greater for women than men.
•    We also find evidence that men are more willing to contribute to public goods.
•    Overall, the compliance effect dominates the free-riding effect for the parameters in the experiment such that women bear a greater burden of the provision of the public good.

Abstract: The existing experimental literature suggests women are more compliant than men when paying taxes but may free ride more when contributing to public goods. It is unclear which effect dominates when paying for public goods through taxation. Experiments conducted in three European countries and the U.S. are used to investigate this issue. The results suggest that women bear a greater burden of the provision of public goods for the parameters in the experiment. The results indicate the gender gap in compliance is due to differences in both the extensive and intensive margins.

Keywords: Individual income tax; Public goods; Gender; Experiments
JEL codes:     H2; H26; C91

My comment: As if it were some kind of compensation, women hide less from taxation and smaller amounts than men, but men are more willing to contribute more if the benefits for all increase.