DOCSLIB.ORG

Bonobos (Pan Paniscus) Show an Attentional Bias Toward Conspecifics’ Emotions

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

Bonobos (Pan paniscus) show an attentional bias toward conspecifics’ emotions Mariska E. Kreta,1, Linda Jaasmab, Thomas Biondac, and Jasper G. Wijnend aInstitute of Psychology, Cognitive Psychology Unit, Leiden University, 2333 AK Leiden, The Netherlands; bLeiden Institute for Brain and Cognition, 2300 RC Leiden, The Netherlands; cApenheul Primate Park, 7313 HK Apeldoorn, The Netherlands; and dPsychology Department, University of Amsterdam, 1018 XA Amsterdam, The Netherlands Edited by Susan T. Fiske, Princeton University, Princeton, NJ, and approved February 2, 2016 (received for review November 8, 2015) In social animals, the fast detection of group members’ emotional perspective, it is most adaptive to be able to quickly attend to rel- expressions promotes swift and adequate responses, which is cru- evant stimuli, whether those are threats in the environment or an cial for the maintenance of social bonds and ultimately for group affiliative signal from an individual who could provide support and survival. The dot-probe task is a well-established paradigm in psy- care (24, 25). chology, measuring emotional attention through reaction times. Most primates spend their lives in social groups. To prevent Humans tend to be biased toward emotional images, especially conflicts, they keep close track of others’ behaviors, emotions, and when the emotion is of a threatening nature. Bonobos have rich, social debts. For example, chimpanzees remember who groomed social emotional lives and are known for their soft and friendly char- whom for long periods of time (26). In the chimpanzee, but also in acter. In the present study, we investigated (i) whether bonobos, the rarely studied bonobo, grooming is a major social activity and similar to humans, have an attentional bias toward emotional scenes a means by which animals living in proximity may bond and re- ii compared with conspecifics showing a neutral expression, and ( ) inforce social structures. It is also used as a form of reconciliation which emotional behaviors attract their attention the most. As pre- and a means of conflict resolution. Despite their general similar- ’ dicted, results consistently showed that bonobos attention was bi- ities and close phylogenetic relationship, bonobos, chimpanzees, ased toward the location of the emotional versus neutral scene. and humans show clear differences in their social behavior. Al- Interestingly, their attention was grabbed most by images showing though chimpanzee and human societies are dominated by males conspecifics such as sexual behavior, yawning, or grooming, and not and encounters between different groups frequently result in vi- as much—as is often observed in humans—by signs of distress or olence and sometimes the killing of conspecifics (27–29), bonobo aggression. The results suggest that protective and affiliative behav- society is controlled by females and aggression is usually prevented iors are pivotal in bonobo society and therefore attract immediate – attention in this species. through nonconceptive sexual behavior, grooming, and play (30 33). Compared with chimpanzees, bonobos live in more predict- bonobo | ape | affect | empathy | attention able environments with low seasonality and stable food availabil- ity, which is why they have a lower degree of fission-fusion and which, next to the peace-keeping role of the females, may also fficiently responding to others’ emotions has great survival explain the lower rates of competition (31). value, especially for social species, such as primates, who es- E Bonobos have rich personalities and share most of their traits tablish close, long-term bonds with group members (1–3). Previous with humans and chimpanzees, suggesting these were also pre- research in humans has shown that one component of this strong sent in their common ancestor (34). From early age on, bonobos sensitivity to others’ emotions is heightened attention to their af- fective states (4–6). Together with the chimpanzee, the bonobo is the closest living relative of humans. Studying components of their Significance emotional behavior, such as emotional attention, may help us not only to understand this rarely studied species better, but also Applying well-established psychological paradigms to our provide insight into (human) emotions and their evolutionary past closest relatives represents a promising approach for providing (7–9). In the present study, we investigated whether bonobos, like insight into similarities and differences between humans and humans, show increased attention to scenes depicting conspe- apes. Numerous articles have been published on the dot-probe cifics showing an emotion or are involved in emotion regulatory task, showing that humans have an attentional bias toward behaviors, compared with scenes where conspecifics are in a emotions, especially when threatening. For social species like ’ neutral state. primates, efficiently responding to others emotions has great In natural environments, attention is preferentially sustained survival value. Observational research has shown that, com- pared with humans and chimpanzees, bonobos excel in reg- by stimuli that have affective significance, in contrast to routine, ’ emotionally neutral events (6, 10). This attentional bias reflects a ulating their own and others emotions, thereby preventing conflicts from escalating. The present study is an initial effort to functional mechanism where fast and automatic attention allo- apply a psychological test to the bonobo, and demonstrates that cation to emotional information can aid humans in threatening they, like humans, have heightened attention to emotional— situations by fostering fast actions (11, 12). Experimentally, this compared with neutral—conspecifics, but are mostly drawn has, for example, been demonstrated with the dot-probe task. toward protective and affiliative emotions. Previous dot-probe studies have shown that emotional signals in- duce a bias in spatial attention, in that participants respond faster COGNITIVE SCIENCES Author contributions: M.E.K., T.B., and J.G.W. designed research; L.J. performed research; PSYCHOLOGICAL AND to a presented dot (the target, henceforth, “probe”)whenitap- M.E.K. and L.J. analyzed data; M.E.K. wrote the paper; T.B. facilitated the research in the pears at the location of a previously presented emotion compared park; and J.G.W. programmed the task. with neutral stimulus (13–17). Although in humans a bias toward The authors declare no conflict of interest. threatening compared with neutral stimuli is most commonly ob- This article is a PNAS Direct Submission. served, some studies also report increased attention toward posi- Freely available online through the PNAS open access option. tive versus neutral stimuli (18–21). Other research has shown that 1To whom correspondence should be addressed. Email: [email protected]. there are marked individual differences in biases and that these This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10. are, for example, modulated by mood (22, 23). From an evolutionary 1073/pnas.1522060113/-/DCSupplemental. www.pnas.org/cgi/doi/10.1073/pnas.1522060113 PNAS | April 5, 2016 | vol. 113 | no. 14 | 3761–3766 Downloaded by guest on September 25, 2021 are sensitive to others’ emotions, which is demonstrated by their Results ability to provide appropriate consolatory behaviors after con- Reaction Times. Data were analyzed in a generalized mixed multi- flicts (35), a skill individuals with more effective self-regulation level model with picture category [emotional bonobo, neutral capabilities excel in particularly (35), but which is also demon- bonobo, or control animal (coded as 1, 0, and −1)] as fixed factor strated by more automatic behavior, including yawn contagion, and random intercepts for each individual and individual-by- an index of empathy (36, 37). session. The multilevel structure was defined by the different Bonobos’ personality characteristics and complex social emo- trials, nested within sessions, nested within individuals. As the tional behavior have rarely been studied experimentally, but reaction time data were skewed, a γ-probability distribution was the conclusions that can be drawn from the few studies avail- selected with a log-link function (Methods). able are in line with the conclusions from observational re- As predicted, a main effect of picture category [F(2, 1.171) = search, described above. It has for example been demonstrated 5.135, P = 0.006] showed that bonobos were faster in tapping on that great apes, bonobos included, can reliably recognize human the probe that replaced a picture of an emotional bonobo (mean emotions (38) and experiments with chimpanzees show that reaction time = 611.240, SE = 78.819) compared with a neutral they are also sensitive to the emotions of conspecifics (39–42). bonobo [mean reaction time = 645.927, SE = 83.176, t(1.171) = By using an experimental cofeeding set-up, it has been shown 2.669, P = 0.008] (Fig. 2A and Table S2) (details on all the sta- that bonobos are more tolerant than chimpanzees (43; but see tistical tests described in the main text are provided in tables in the ref. 44). In addition, an eye-tracking study demonstrated that SI Results). This pattern was visible in all subjects (Fig. 2B). bonobos make more eye contact than chimpanzees (45). Finally, Although luminance or contrast could not explain the differ- in a risky decision game, bonobos showed more risk-aversion ences in reaction times following the emotional
Recommended publications
  • EAZA Best Practice Guidelines Bonobo (Pan Paniscus)

    EAZA Best Practice Guidelines Bonobo (Pan Paniscus)

    EAZA Best Practice Guidelines Bonobo (Pan paniscus) Editors: Dr Jeroen Stevens Contact information: Royal Zoological Society of Antwerp – K. Astridplein 26 – B 2018 Antwerp, Belgium Email: [email protected] Name of TAG: Great Ape TAG TAG Chair: Dr. María Teresa Abelló Poveda – Barcelona Zoo [email protected] Edition: First edition - 2020 1 2 EAZA Best Practice Guidelines disclaimer Copyright (February 2020) by EAZA Executive Office, Amsterdam. All rights reserved. No part of this publication may be reproduced in hard copy, machine-readable or other forms without advance written permission from the European Association of Zoos and Aquaria (EAZA). Members of the European Association of Zoos and Aquaria (EAZA) may copy this information for their own use as needed. The information contained in these EAZA Best Practice Guidelines has been obtained from numerous sources believed to be reliable. EAZA and the EAZA APE TAG make a diligent effort to provide a complete and accurate representation of the data in its reports, publications, and services. However, EAZA does not guarantee the accuracy, adequacy, or completeness of any information. EAZA disclaims all liability for errors or omissions that may exist and shall not be liable for any incidental, consequential, or other damages (whether resulting from negligence or otherwise) including, without limitation, exemplary damages or lost profits arising out of or in connection with the use of this publication. Because the technical information provided in the EAZA Best Practice Guidelines can easily be misread or misinterpreted unless properly analysed, EAZA strongly recommends that users of this information consult with the editors in all matters related to data analysis and interpretation.
  • Measuring Engagement Elicited by Eye Contact in Human-Robot Interaction

    Measuring Engagement Elicited by Eye Contact in Human-Robot Interaction

    Measuring engagement elicited by eye contact in Human-Robot Interaction Kompatsiari K., Ciardo F., De Tommaso D., Wykowska A., Member, IEEE Abstract— The present study aimed at investigating how eye interactions, people are often not aware that their brains contact established by a humanoid robot affects engagement in employ certain mechanisms and processes. However, thanks human-robot interaction (HRI). To this end, we combined to the careful design of experimental paradigms inspired by explicit subjective evaluations with implicit measures, i.e. research in cognitive psychology or cognitive/social reaction times and eye tracking. More specifically, we employed neuroscience that target and focus on specific mechanisms, we a gaze cueing paradigm in HRI protocol involving the iCub can collect objective implicit metrics and draw conclusions robot. Critically, before moving its gaze, iCub either established about what specific cognitive processes are at stake [15-17]. eye contact or not with the user. We investigated the patterns of Typically, psychologists use performance measures (reaction fixations of participants’ gaze on the robot’s face, joint attention times, error rates) to study mechanisms of perception, and the subjective ratings of engagement as a function of eye cognition, and behavior, and also the social aspects thereof: for contact or no eye contact. We found that eye contact affected example, joint attention [e.g., 15-22 , or visuo-spatial implicit measures of engagement, i.e. longer fixation times on the ] robot’s face during eye contact, and joint attention elicited only perspective taking [23-24]. As such, these measures have after the robot established eye contact. On the contrary, explicit informed researchers about the respective cognitive processes measures of engagement with the robot did not vary across with high reliability, and without the necessity of participants conditions.
  • Gorilla Beringei (Eastern Gorilla) 07/09/2016, 02:26

    Gorilla Beringei (Eastern Gorilla) 07/09/2016, 02:26

    Gorilla beringei (Eastern Gorilla) 07/09/2016, 02:26 Kingdom Phylum Class Order Family Animalia ChordataMammaliaPrimatesHominidae Scientific Gorilla beringei Name: Species Matschie, 1903 Authority: Infra- specific See Gorilla beringei ssp. beringei Taxa See Gorilla beringei ssp. graueri Assessed: Common Name(s): English –Eastern Gorilla French –Gorille de l'Est Spanish–Gorilla Oriental TaxonomicMittermeier, R.A., Rylands, A.B. and Wilson D.E. 2013. Handbook of the Mammals of the World: Volume Source(s): 3 Primates. Lynx Edicions, Barcelona. This species appeared in the 1996 Red List as a subspecies of Gorilla gorilla. Since 2001, the Eastern Taxonomic Gorilla has been considered a separate species (Gorilla beringei) with two subspecies: Grauer’s Gorilla Notes: (Gorilla beringei graueri) and the Mountain Gorilla (Gorilla beringei beringei) following Groves (2001). Assessment Information [top] Red List Category & Criteria: Critically Endangered A4bcd ver 3.1 Year Published: 2016 Date Assessed: 2016-04-01 Assessor(s): Plumptre, A., Robbins, M. & Williamson, E.A. Reviewer(s): Mittermeier, R.A. & Rylands, A.B. Contributor(s): Butynski, T.M. & Gray, M. Justification: Eastern Gorillas (Gorilla beringei) live in the mountainous forests of eastern Democratic Republic of Congo, northwest Rwanda and southwest Uganda. This region was the epicentre of Africa's "world war", to which Gorillas have also fallen victim. The Mountain Gorilla subspecies (Gorilla beringei beringei), has been listed as Critically Endangered since 1996. Although a drastic reduction of the Grauer’s Gorilla subspecies (Gorilla beringei graueri), has long been suspected, quantitative evidence of the decline has been lacking (Robbins and Williamson 2008). During the past 20 years, Grauer’s Gorillas have been severely affected by human activities, most notably poaching for bushmeat associated with artisanal mining camps and for commercial trade (Plumptre et al.
  • Conflict and Cooperation in Wild Chimpanzees

    Conflict and Cooperation in Wild Chimpanzees

    ADVANCES IN THE STUDY OF BEHAVIOR VOL. 35 Conflict and Cooperation in Wild Chimpanzees MARTIN N. MULLER* and JOHN C. MITANIt *DEPARTMENT OF ANTHROPOLOGY BOSTON UNIVERSITY BOSTON, MASSACHUSETTS, 02215, USA tDEPARTMENT OF ANTHROPOLOGY UNIVERSITY OF MICHIGAN ANN ARBOR, MICHIGAN, 48109, USA 1. INTRODUCTION The twin themes of competition and cooperation have been the focus of many studies in animal behavior (Alcock, 2001; Dugatkin, 2004; Krebs and Davies, 1997). Competition receives prominent attention because it forms the basis for the unifying, organizing principle of biology. Darwin's (1859) theory of natural selection furnishes a powerful framework to understand the origin and maintenance of organic and behavioral diversity. Because the process of natural selection depends on reproductive competition, aggression, dominance, and competition for mates serve as important foci of ethological research. In contrast, cooperation in animals is less easily explained within a Darwinian framework. Why do animals cooperate and behave in ways that benefit others? Supplements to the theory of natural selection in the form of kin selection, reciprocal altruism, and mutualism provide mechanisms that transform the study of cooperative behavior in animals into a mode of inquiry compatible with our current understand- ing of the evolutionary process (Clutton-Brock, 2002; Hamilton, 1964; Trivers, 1971). If cooperation can be analyzed via natural selection operating on indivi- duals, a new way to conceptualize the process emerges. Instead of viewing cooperation as distinct from competition, it becomes productive to regard them together. Students of animal behavior have long recognized that an artificial dichotomy may exist insofar as animals frequently cooperate to compete with conspecifics.
  • The Cognitive Animal Empirical and Theoretical Perspectives on Animal Cognition

    The Cognitive Animal Empirical and Theoretical Perspectives on Animal Cognition

    This PDF includes a chapter from the following book: The Cognitive Animal Empirical and Theoretical Perspectives on Animal Cognition © 2002 Massachusetts Institute of Technology License Terms: Made available under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Public License https://creativecommons.org/licenses/by-nc-nd/4.0/ OA Funding Provided By: The open access edition of this book was made possible by generous funding from Arcadia—a charitable fund of Lisbet Rausing and Peter Baldwin. The title-level DOI for this work is: doi:10.7551/mitpress/1885.001.0001 Downloaded from http://direct.mit.edu/books/edited-volume/chapter-pdf/677498/9780262268028_c002400.pdf by guest on 25 September 2021 Chimpanzee Ai and Her Son Ayumu: An Episode of Education by Master- 25 Apprenticeship Tetsuro Matsuzawa I have been studying chimpanzee (Pan troglo- use has never before been found in nonhuman dytes) intelligence both in the laboratory and animals. Humans show strong hand preference in the wild (Matsuzawa 2001). Chimpanzees in on the individual level, and there is also a strong the wild use and manufacture a wide variety of right bias at the population level. The chimpan- tools, such as twigs to fish for termites or a pair zees of Bossou show a slight bias toward the of stones to crack open hard-shelled nuts. Re- right for hammering at the population level, with cent studies comparing di¤erent communities of about 67 percent of group members being right- chimpanzees have shown that each community handers. However, there is perfect correspon- develops its own unique set of cultural traditions.
  • Orangutan…Taxonomy…And…Nomenclature

    Orangutan…Taxonomy…And…Nomenclature

    «««« ORANGUTAN…TAXONOMY…AND…NOMENCLATURE« « Craig«D em itros« « The«taxonom y«of«the«orangutan«has«been«confusing«and«is«still«the«subject«of« m uch«debate.«Q uestions«at«the«specific«and«subspecific«level«are«still«being« investigated«(Courtenay«et«al.«1988).«The«follow ing«taxonom ic«inform ation«is« taken«prim arily«from «G roves,«1971.« « H IG H ER«LEVEL«TAXO N O M Y:« O rder:«Prim ates« Suborder:«A nthropoidea« Superfam ily:«H om inoidea« Fam ily:«Pongidae«(Includes«extant«genera«Pan,…Gorilla…and…Pongo).« « H ISTO RICA L«TAXO N O M Y«AT«TH E«G EN U S«A N D «G EN U S«SPECIES«LEVEL:«« G enus« Pongo«Lacepede,«1799.« O urangus«Zim m erm an,«1777«(N am e«invalidated).« « G enus«species«(Pongo…pygm aeus«H oppius,«1763).« Sim ia…pygm aeus«H oppius,«1763.««Type«locality«Sum atra.« Sim ia…satyrus«Linnaeus,«1766.« O urangus…outangus«Zim m erm an,«1777.« Pongo…borneo«Lacepede,«1799.««Type«locality«Borneo.« Sim ia…Agrais«Schreber,«1779.««Type«locality«Borneo.« Pongo…W urm bii«Tiedem ann,«1808.««Type«locality«Borneo.« Pongo…Abelii«Lesson,«1827.««Type«locality«Sum atra.« Sim ia…M orio«O w en,«1836.««Type«locality«Borneo.« Pithecus…bicolor«I.«G eoffroy,«1841.««Type«locality«Sum atra.« Sim ia…Gargantica«Pearson,«1841.««Type«locality«Sum atra.« Pithecus…brookei«Blyth,«1853.««Type«locality«Saraw ak.« Pithecus…ow enii«Blyth,«1853.««Type«locality«Saraw ak.« Pithecus…curtus«Blyth,«1855.««Type«locality«Saraw ak.« Satyrus…Knekias«M eyer,«1856.««Type«locality«Borneo.« Pithecus…W allichii«G ray,«1870.««Type«locality«Borneo.« Pithecus…sum atranus«Selenka,«1896.««Type«locality«Sum atra.« Pongo…pygm aeus«Rothschild,«1904.««First«use«of«this«com bination.« Ptihecus…w allacei«Elliot,«1913.««Type«locality«Borneo.« « CURRENT…TAXONOMY« « The«current«and«m ost«accepted«taxonom y«of«the«G enus«Pongo«includes«one« species«Pongo…pygm aeus«and«tw o«subspecies«P.p.…pygm aeus«(the«Bornean« subspecies)«and«P.p.…abelii«(the«Sum atran«subspecies)«(Bem m el«1968;«Jones« 1969;«G roves«1971;«Jacobshagen«1979;«Seuarez«et«al.«1979«and«G roves«1993).« 5« « .
  • Cross-River Gorillas

    Cross-River Gorillas

    CMS Agreement on the Distribution: General Conservation of Gorillas UNEP/GA/MOP3/Inf.9 and their Habitats of the 24 April 2019 Convention on Migratory Species Original: English THIRD MEETING OF THE PARTIES Entebbe, Uganda, 18-20 June 2019 REVISED REGIONAL ACTION PLAN FOR THE CONSERVATION OF THE CROSS RIVER GORILLA (Gorilla gorilla diehli) 2014 - 2019 For reasons of economy, this document is printed in a limited number, and will not be distributed at the meeting. Delegates are kindly requested to bring their copy to the meeting and not to request additional copies. FewerToday, thethan total population of Cross River gorillas may number fewer than 300 individuals 300 left Revised Regional Action Plan for the Conservation of the Cross River Gorilla (Gorilla gorilla diehli) 2014–2019 HopeUnderstanding the status of the changing threats across the Cross River gorilla landscape will provide key information for guiding our collectiveSurvival conservation activities cross river gorilla action plan cover_2013.indd 1 2/3/14 10:27 AM Camera trap image of a Cross River gorilla at Afi Mountain Cross River Gorilla (Gorilla gorilla diehli) This plan outlines measures that should ensure that Cross River gorilla numbers are able to increase at key core sites, allowing them to extend into areas where they have been absent for many years. cross river gorilla action plan cover_2013.indd 2 2/3/14 10:27 AM Revised Regional Action Plan for the Conservation of the Cross River Gorilla (Gorilla gorilla diehli) 2014-2019 Revised Regional Action Plan for the Conservation of the Cross River Gorilla (Gorilla gorilla diehli) 2014-2019 Compiled and edited by Andrew Dunn1, 16, Richard Bergl2, 16, Dirck Byler3, Samuel Eben-Ebai4, Denis Ndeloh Etiendem5, Roger Fotso6, Romanus Ikfuingei6, Inaoyom Imong1, 7, 16, Chris Jameson6, Liz Macfie8, 16, Bethan Mor- gan9, 16, Anthony Nchanji6, Aaron Nicholas10, Louis Nkembi11, Fidelis Omeni12, John Oates13, 16, Amy Pokemp- ner14, Sarah Sawyer15 and Elizabeth A.
  • Proposal for Inclusion of the Chimpanzee

    Proposal for Inclusion of the Chimpanzee

    CMS Distribution: General CONVENTION ON MIGRATORY UNEP/CMS/COP12/Doc.25.1.1 25 May 2017 SPECIES Original: English 12th MEETING OF THE CONFERENCE OF THE PARTIES Manila, Philippines, 23 - 28 October 2017 Agenda Item 25.1 PROPOSAL FOR THE INCLUSION OF THE CHIMPANZEE (Pan troglodytes) ON APPENDIX I AND II OF THE CONVENTION Summary: The Governments of Congo and the United Republic of Tanzania have jointly submitted the attached proposal* for the inclusion of the Chimpanzee (Pan troglodytes) on Appendix I and II of CMS. *The geographical designations employed in this document do not imply the expression of any opinion whatsoever on the part of the CMS Secretariat (or the United Nations Environment Programme) concerning the legal status of any country, territory, or area, or concerning the delimitation of its frontiers or boundaries. The responsibility for the contents of the document rests exclusively with its author. UNEP/CMS/COP12/Doc.25.1.1 PROPOSAL FOR THE INCLUSION OF CHIMPANZEE (Pan troglodytes) ON APPENDICES I AND II OF THE CONVENTION ON THE CONSERVATION OF MIGRATORY SPECIES OF WILD ANIMALS A: PROPOSAL Inclusion of Pan troglodytes in Appendix I and II of the Convention on the Conservation of Migratory Species of Wild Animals. B: PROPONENTS: Congo and the United Republic of Tanzania C: SUPPORTING STATEMENT 1. Taxonomy 1.1 Class: Mammalia 1.2 Order: Primates 1.3 Family: Hominidae 1.4 Genus, species or subspecies, including author and year: Pan troglodytes (Blumenbach 1775) (Wilson & Reeder 2005) [Note: Pan troglodytes is understood in the sense of Wilson and Reeder (2005), the current reference for terrestrial mammals used by CMS).
  • Eye Contact and Social Anxiety Disorder Julia Kane Langer Washington University in St

    Eye Contact and Social Anxiety Disorder Julia Kane Langer Washington University in St

    Washington University in St. Louis Washington University Open Scholarship Arts & Sciences Electronic Theses and Dissertations Arts & Sciences Summer 8-15-2015 Eye Contact and Social Anxiety Disorder Julia Kane Langer Washington University in St. Louis Follow this and additional works at: https://openscholarship.wustl.edu/art_sci_etds Part of the Psychology Commons Recommended Citation Langer, Julia Kane, "Eye Contact and Social Anxiety Disorder" (2015). Arts & Sciences Electronic Theses and Dissertations. 561. https://openscholarship.wustl.edu/art_sci_etds/561 This Dissertation is brought to you for free and open access by the Arts & Sciences at Washington University Open Scholarship. It has been accepted for inclusion in Arts & Sciences Electronic Theses and Dissertations by an authorized administrator of Washington University Open Scholarship. For more information, please contact [email protected]. WASHINGTON UNIVERSITY IN ST. LOUIS Department of Psychology Dissertation Examination Committee: Thomas Rodebaugh, Chair Brian Carpenter Andrew Knight Thomas Oltmanns Renee Thompson Eye Contact and Social Anxiety Disorder by Julia Langer A dissertation presented to the Graduate School of Arts & Sciences of Washington University in partial fulfillment of the requirements for the degree of Doctor of Philosophy August 2015 St. Louis, Missouri © 2014, Julia Langer TABLE OF CONTENTS 1. List of Figures ……………………………………………………… iii 2. List of Tables ……………………………………………………… iv 3. Acknowledgements ……………………………………………………… v 4. Abstract page ……………………………………………………… vi 5. Chapter 1 ……………………………………………………… 1 6. Chapter 2 ……………………………………………………… 22 7. Chapter 3 ……………………………………………………… 33 8. Chapter 4 ……………………………………………………… 49 9. References ……………………………………………………… 57 ii List of Figures Figure 1. Theoretical mediation model of SAD, positive affect, and eye contact ………………………………………………… 3 Figure 2. Mediation model with diagnosis, positive affect, and eye contact ………………………………………………… 16 Figure 3.
  • Lethal Aggression in Pan Is Better Explained by Adaptive Strategies Than Human Impacts

    Lethal Aggression in Pan Is Better Explained by Adaptive Strategies Than Human Impacts

    LETTER doi:10.1038/nature13727 Lethal aggression in Pan is better explained by adaptive strategies than human impacts Michael L. Wilson1,2, Christophe Boesch3, Barbara Fruth4,5, Takeshi Furuichi6, Ian C. Gilby7,8, Chie Hashimoto6, Catherine L. Hobaiter9, Gottfried Hohmann3, Noriko Itoh10, Kathelijne Koops11, Julia N. Lloyd12, Tetsuro Matsuzawa6,13, John C. Mitani14, Deus C. Mjungu15, David Morgan16, Martin N. Muller17, Roger Mundry18, Michio Nakamura10, Jill Pruetz19, Anne E. Pusey7, Julia Riedel3, Crickette Sanz20, Anne M. Schel21, Nicole Simmons12, Michel Waller22, David P. Watts23, Frances White22, Roman M. Wittig3, Klaus Zuberbu¨hler9,24 & Richard W. Wrangham25 Observations of chimpanzees (Pan troglodytes) and bonobos (Pan In contrast, the adaptive strategies hypothesis views killing as an paniscus) provide valuable comparative data for understanding the evolved tactic by which killers tend to increase their fitness through significance of conspecific killing. Two kinds of hypothesis have increased access to territory, food, mates or other benefits1–5,10–17.Kin been proposed. Lethal violence is sometimes concluded to be the selection18 and evolutionary game theory19 yield a set of specific predic- result of adaptive strategies, such that killers ultimately gain fit- tions for how benefits and costs should vary with the context, age, sex, ness benefits by increasing their access to resources such as food or and genetic relatedness of the attackers and targets. Lethal aggression mates1–5. Alternatively, it could be a non-adaptive result of human occurs within a diverse set of circumstances, but is expected to be most impacts, such as habitat change or food provisioning6–9. To discri- commonly committed by males; directed towards males; directed towards minate between these hypotheses we compiled information from non-kin, particularly members of other groups; and committed when 18 chimpanzee communities and 4 bonobo communities studied overwhelming numerical superiority reduces the costs of killing.
  • West African Chimpanzees

    West African Chimpanzees

    Status Survey and Conservation Action Plan West African Chimpanzees Compiled and edited by Rebecca Kormos, Christophe Boesch, Mohamed I. Bakarr and Thomas M. Butynski IUCN/SSC Primate Specialist Group IUCN The World Conservation Union Donors to the SSC Conservation Communications Programme and West African Chimpanzees Action Plan The IUCN Species Survival Commission is committed to communicating important species conservation information to natural resource managers, decision makers and others whose actions affect the conservation of biodiversity. The SSC’s Action Plans, Occasional Papers, newsletter Species and other publications are supported by a wide variety of generous donors including: The Sultanate of Oman established the Peter Scott IUCN/SSC Action Plan Fund in 1990. The Fund supports Action Plan development and implementation. To date, more than 80 grants have been made from the Fund to SSC Specialist Groups. The SSC is grateful to the Sultanate of Oman for its confidence in and support for species conservation worldwide. The Council of Agriculture (COA), Taiwan has awarded major grants to the SSC’s Wildlife Trade Programme and Conser- vation Communications Programme. This support has enabled SSC to continue its valuable technical advisory service to the Parties to CITES as well as to the larger global conservation community. Among other responsibilities, the COA is in charge of matters concerning the designation and management of nature reserves, conservation of wildlife and their habitats, conser- vation of natural landscapes, coordination of law enforcement efforts, as well as promotion of conservation education, research, and international cooperation. The World Wide Fund for Nature (WWF) provides significant annual operating support to the SSC.
  • And Chimpanzees (Pan Troglodytes)

    And Chimpanzees (Pan Troglodytes)

    Received: 21 November 2016 | Revised: 1 August 2017 | Accepted: 14 August 2017 DOI: 10.1002/ajpa.23303 RESEARCH ARTICLE Comparison of hand use and forelimb posture during vertical climbing in mountain gorillas (Gorilla beringei beringei)and chimpanzees (Pan troglodytes) Johanna Neufuss1 | Martha M. Robbins2 | Jana Baeumer2 | Tatyana Humle3 | Tracy L. Kivell1,4 1Animal Postcranial Evolution (APE) Laboratory, Skeletal Biology Research Abstract Centre, School of Anthropology & Objectives: Studies on grasping and limb posture during arboreal locomotion in great apes in their Conservation, University of Kent, Canterbury, United Kingdom natural environment are scarce and thus, attempts to correlate behavioral and habitat differences 2Department of Primatology, Max Planck with variation in morphology are limited. The aim of this study is to compare hand use and fore- Institute for Evolutionary Anthropology, limb posture during vertical climbing in wild, habituated mountain gorillas (Gorilla beringei beringei) Leipzig, Germany and semi-free-ranging chimpanzees (Pan troglodytes) to assess differences in the climbing styles 3 Durrell Institute of Conservation and that may relate to variation in hand or forelimb morphology and body size. Ecology, School of Anthropology & Conservation, University of Kent, Materials and methods: We investigated hand use and forelimb posture during both ascent and Canterbury, United Kingdom descent vertical climbing in 15 wild mountain gorillas and eight semi-free-ranging chimpanzees, 4 Department of Human Evolution, Max using video records obtained ad libitum. Planck Institute for Evolutionary Anthropology, Leipzig, Germany Results: In both apes, forelimb posture was correlated with substrate size during both ascent and Correspondence descent climbing. While climbing, both apes used power grips and diagonal power grips, including Johanna Neufuss.