Facial width-to-height ratio relates to alpha status and assertive personality in capuchin monkeys

Social dominance hierarchies play a pivotal role in shaping the behaviour of many species, and sex differences within these hierarchies often exist. To date, however, few physical markers of dominance have been identified. Such markers would be valuable in terms of understanding the etiology of dominant behaviour and changes in social hierarchies over time. Animals may also use such traits to evaluate the potential dominance of others relative to themselves (i.e. a physical “cue”). Facial width-to-height ratio (fWHR), for example, has been suggested as a cue to dominance in humans, with links to both dominant behaviour and the perception of dominance in other individuals. Whether this association is present in non-human animals is currently not known. Therefore, here we examine within-species links between fWHR and dominant behaviour in 64 brown capuchin monkeys (Sapajus spp.) aged between 2 and 40 years. fWHR was positively associated with alpha status and with a dimensional rating of assertive personality in both males and females. Moreover, fWHR showed significant sexual dimorphism in adults but not juveniles, suggesting a developmental change may occur during puberty. In a sub-sample, sex differences were mediated by weight, suggesting fWHR dimorphism does not exceed what would be expected by differences in body weight. This is the first report of an association between face shape and behaviour in a non-human species. Results are discussed in terms of the role that face-behaviour associations might play within capuchin societies, and the possible selective forces that might have led to the evolution of fWHR-dominance associations in humans

Facial masculinity:How the choice of measurement method enables to detect its influence on behaviour

Recent research has explored the relationship between facial masculinity, human male behaviour and males' perceived features (i.e. attractiveness). The methods of measurement of facial masculinity employed in the literature are quite diverse. In the present paper, we use several methods of measuring facial masculinity to study the effect of this feature on risk attitudes and trustworthiness. We employ two strategic interactions to measure these two traits, a first-price auction and a trust game. We find that facial width-to-height ratio is the best predictor of trustworthiness, and that measures of masculinity which use Geometric Morphometrics are the best suited to link masculinity and bidding behaviour. However, we observe that the link between masculinity and bidding in the first-price auction might be driven by competitiveness and not by risk aversion only. Finally, we test the relationship between facial measures of masculinity and perceived masculinity. As a conclusion, we suggest that researchers in the field should measure masculinity using one of these methods in order to obtain comparable results. We also encourage researchers to revise the existing literature on this topic following these measurement methods

Lack of support for the association between facial shape and aggression: a reappraisal based on a worldwide population genetics perspective

Antisocial and criminal behaviors are multifactorial traits whose interpretation relies on multiple disciplines. Since these interpretations may have social, moral and legal implications, a constant review of the evidence is necessary before any scientific claim is considered as truth. A recent study proposed that men with wider faces relative to facial height (fWHR) are more likely to develop unethical behaviour mediated by a psychological sense of power. This research was based on reports suggesting that sexual dimorphism and selection would be responsible for a correlation between fWHR and aggression. Here we show that 4,960 individuals from 94 modern human populations belonging to a vast array of genetic and cultural contexts do not display significant amounts of fWHR sexual dimorphism. Further analyses using populations with associated ethnographical records as well as samples of male prisoners of the Mexico City Federal Penitentiary condemned by crimes of variable level of inter-personal aggression (homicide, robbery, and minor faults) did not show significant evidence, suggesting that populations/individuals with higher levels of bellicosity, aggressive behaviour, or power-mediated behaviour display greater fWHR. Finally, a regression analysis of fWHR on individual"s fitness showed no significant correlation between this facial trait and reproductive success. Overall, our results suggest that facial attributes are poor predictors of aggressive behaviour, or at least, that sexual selection was weak enough to leave a signal on patterns of between- and within-sex and population facial variation

Masculinity cues, perceptions of politician attributes, and political behavior*

How are masculine-looking politicians perceived by voters? Are these judgments accurate? We asked Australian survey participants to rate images of unknown-to-them Swiss politicians. We find that politicians with prominent markers of masculinity (including facial hair, baldness, and higher facial width-to-height ratio) are perceived as less honest and competent. To determine whether these perceptions correlate with political behavior, we exploit two unique features of Swiss politics. First, to check for politician–voter congruence, we match each politician's voting record to that of their constituents on identically worded legislative proposals. We find that bearded politicians are less likely to behave according to constituents' preferences. Second, by exploiting the mandatory disclosure of lobby group affiliations, we show that bearded politicians are less likely to be captured by interest groups. Our results suggest that more masculine-looking politicians are recognized by both voters and lobby groups as less amenable to being controlled.</p

Photovoltaische Anlagen Leitfaden fuer Elektriker, Dachdecker, Fachplaner, Architekten und Bauherren

can-polluting and sustainable power supply will rely heavily on photovoltaic systems. Experience has shown that the development of PV systems cannot be assured without careful, high-quality planning dimensioning, installation, commissioning and maintenance. This guide contains comprehensive information on all aspects of PV systems. It addresses architects, projecting engineers, builder-owners, electricians and roofers, as well as decision-makers on state and community level with the intention of informing them on the latest state of the art. Contents: 1. Functional principles, design, characteristics and properties of components, modules and current inverters; 2. in situ analysis and site analysis; 3. shading analysis; 4. Optimal planning, dimensioning and design; 5. simulation programmes; 6. installation, commissioning, failure detection and maintenance; 7. assembly systems and integration options; 8. funding programmes. To facilitate updating, the book is in the form of a loose-leaf collection.Fuer eine klimavertraegliche und nachhaltige zukuenftige Energieversorgung Deutschlands ist der massive Ausbau der Photovoltaik unabdingbar. Die Rahmenbedingungen fuer einen solchen Ausbau sind geschaffen, der Markt befindet sich zur Zeit im Umbruch. In Deutschland werden von einem solchen Ausbau in erster Linie netzgekoppelte PV-Anlagen betroffen sein. Die Erfahrungen mit der Performance solcher Anlagen (1.000-Daecher-Programm, Programm Sonne in der Schule, Schweizer Foerderprogramm etc.) haben allerdings gezeigt, dass ohne eine sorgfaeltige und auf hohem Niveau stehende Planung, Dimensionierung, Installation, Inbetriebnahme und Wartung der optimale Ertrag und damit der Beitrag zum Klimaschutz nicht gewaehrleistet werden kann. Aus diesen Gruenden ist es notwendig und sinnvill, Architekten, Planern, Bauherren, Installationsbetrieben (sowohl Elektrikern als auch Dachdeckern) und last but not least den Entscheidungstraegern in Laendern und Kommunen ein Nachschlagewerk in die Hand zu geben, das all die oben genannten Aspekte ausfuehrlich behandelt. Der Leitfaden soll so alle Beteiligten in die Lage versetzen, Photovoltaikanlagen dem neuesten Stand der Technik entsprechend qualitaetsbewusst zu planen, zu installieren und in Betrieb zu nehmen. Schwerpunkte sind hierbei (1) Funktionsprinzipien, Aufbau, Eigenschaften und Kennwerte der Komponenten, Module und Wechselrichter (b) Vororttermin und Standortanalyse (c) Verschattungsanalyse (d) Optimale Planung, Dimensionierung und Auslegung (e) Simulationsprogramme (f) Installation, Inbetriebnahme, Fehlersuche und Wartung (g) Montagesysteme und Integrationsmoeglichkeiten (h) Foerderprogramme. Eine vollstaendige Uebersicht der auf dem Markt erhaeltichen Module, Wechselrichter und Montagesysteme erleichert dem Planer und Installateur die Vorauswahl von Komponenten. Der Leitfaden ist als Loseblattsammloung konzipiert, um die Anwendung und spaetere Aktualisierung sowie Erweiterung flexibel und einfach zu gestalten. (orig.)SIGLEAvailable from TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSenatsverwaltung fuer Stadtentwicklung, Berlin (Germany); Ministerium fuer Wirtschaft, Mittelstand und Technologie des Landes Brandenburg, Potsdam (Germany)DEGerman

The Influence of Facial Width-to-Height Ratio on Micro-expression Recognition

Part 5: Perceptual IntelligenceInternational audienceThe aim of the present study was to uncover the potential impact of facial width-to-height ratio (fWHR) on micro-expression and macro-expression recognition. The JACBART paradigm was used for the presentation of facial expressions. Participants were asked to recognize six kinds of basic expressions (sadness, surprise, anger, disgust, fear, happiness) on high fWHR faces or on low fWHR faces under 67 ms, 333 ms and 600 ms duration conditions respectively. The results indicated that, the fWHR did not affect the recognition of macro-expressions which were presented for 600 ms in the present study, but the fWHR could influence the recognition accuracy of micro-expressions of surprise and happiness. Specifically, participants could identify the facial expression of surprise more effectively on high fWHR faces than on low fWHR faces under the condition of 67 ms. And participants also could recognize the facial expression of happiness more accurately on high fWHR faces in the conditions of 67 ms and 333 ms. These results revealed the facial expressions of happiness and surprise on high fWHR faces may have an early processing advantage in micro-expression recognition. And the result also demonstrated that individuals spontaneously use fWHR as a clue to recognize micro-expressions