Speakers & Topics

Sarah Brosnan     
“Responses to inequity and prosocial behavior in chimpanzees”
Chimpanzees respond negatively to distributional inequity, disliking it when they receive less reward than a conspecific for a particular task. However, the response is quite nuanced, and the social environment of the chimpanzee strongly affects their responses, with individuals showing an ameliorated response among individuals with whom they have lived most or all of their lifetimes. Moreover, this response is apparently self-regarding; in both the original study and further studies, chimpanzees are indifferent to the outcome of their partner, but change their responses only when they themselves receive a lesser reward.

Frans de Waal     
“A social brain: Chimpanzees and the negotiation of social relationships”
It is in the social domain that one sees the full potential of chimpanzee intelligence. Power politics, tit-for-tat, the need to overcome conflict and cultural transmission pose profound intellectual challenges that have shaped the chimpanzee brain.

Misato Hayashi     
“Development of object manipulation tasks by chimpanzees and humans”*
Cognitive development in chimpanzees was assessed by object manipulation tasks. In a face-to-face situation, the chimpanzee subjects received the following tasks: a nesting-cup task, a stacking-block task and so on. The analysis of manipulation patterns can be an indicator of cognitive ability in both chimpanzees and humans.

Satoshi Hirata     
“Chimpanzees solve a cooperative task”*
To explore chimpanzee cooperative behavior, two individuals were given the task of pulling both ends of a string simultaneously to draw in two blocks on which food was placed. The results show that the chimpanzees were able to cooperate after some trial and error and that active recruiting behavior emerges depending on the past history of interaction between partners.

William Hopkins     
“Advanced imaging techniques and the study of gestures and tool-use in chimpanzees”*
In the past 20 years, the development of non-invasive imaging technologies have provided a means for examining the association between various motor and cognitive functions and underlying neural activity in humans. In this paper, I will describe the application of magnetic resonance imaging (MRI) and positron emission tomography (PET) to the study of gestural communication and tool use in chimpanzees.

Vicky Horner     
“Cultural transmission in captive chimpanzees”*
This talk will describe a series of studies conducted with two groups of captive chimpanzees at Yerkes National Primate Center’s Field Station. These studies have been designed to simulate the innovation and subsequent transmission of separate cultural variants in each group. Experimental paradigms are designed, as far as possible, to mimic behaviors exhibited by wild chimpanzee populations in Africa.

Tatyana Humle     
“Conditions influencing the cultural transmission of ant-dipping behavior in wild chimpanzees”*
The current evidence for culture in chimpanzees, as well as in other animal species, raises essential questions as to how cultural variants arise and are maintained and propagated between and within generation of a population as well as which social and environmental conditions influence and favor these processes. Long-term data on ant-dipping—a tool use behavior aimed at driver ants—in wild chimpanzees will be used to shed a new perspective on culture and especially on the interaction between individual behavioral adaptation to the environment and the role of social mediation in behavioral acquisition.

Masaki Tomonaga     
"Chimpanzee Early Social Cognition"
We have conducted a series of studies on the developmental changes in social cognition in mother-raised infant chimpanzees from birth to around two years of age. The infants preferentially tracked a photograph of their mother’s face at one month but showed indifferent preferences to faces at two months. This change in facial recognition was correlated with a decrease in neonatal spontaneous smiling, increase in social smiling and a decline in neonatal imitation of facial expressions. Also at around two months, the infants began to show preferences for directed-gaze faces over averted gazes, and the amount of mutual gaze time between mother and infant chimpanzees increased. Thus, by two months of age, abilities required for dyadic interactions are already developed in chimpanzees as is the case in humans. The development of triadic interactions, however, is rather different between these two species. The infant chimpanzee can follow another’s pointing or gaze at around one year, but even by two years of age does not “share” attention with the others.

Tetsuro Matuszawa     
“The history of the Understanding Chimpanzees conference series”*
The series of Chicago symposia on "Understanding Chimpanzees" have illuminated various aspects of chimpanzees, our evolutionary neighbors. I have been studying the chimpanzee mind since 1978, my research partner being a chimpanzee named "Ai." The present talk will focus on this research, synthesizing the laboratory work and fieldwork to know the chimpanzee mind as a whole.

Lisa Parr     
“Chimpanzee facial expressions”*
Facial expressions are complex visual signals that are essential for maintaining social relationships among primates. This talk will focus on new techniques for identifying chimpanzee facial expressions and present data describing how chimpanzees categorize these expressions in computerized tasks. Results help us to understand the evolution of emotion.

Crickette Sanz     
“Tool-use behavior by chimpanzees of the Goualougo Triangle”*
Our knowledge of diversity and variation in chimpanzee tool-using behavior has continuously expanded with insights from long-term research sites and the initiation of new field studies of wild populations. In this context, I present observations of tool use and tool making in several adjacent chimpanzee communities from the Goualougo Triangle in the northern Republic of Congo. I will discuss complexity and flexibility in these behaviors as well as specific ecological constraints and opportunities in the Ndoki forests.

Andrew Whiten     
“Cultural Panthropology”
The idea of chimpanzee culture has been around since the earliest discoveries of tool use at Gombe, but decades of field research have yielded an unprecedented bird’s eye view of “cultural panthropology” across Africa. This talk will review the latest findings emanating from the Collaborative Chimpanzee Cultures Project (CCCP) and the complementary discoveries of the “Two Cultures Experiment” being conducted with captive groups of chimpanzees. This work continues to lead work in the wider arena of “animal culture."

Dora Biro     
“Field experiments on tool-use behaviour with the chimpanzees of Bossou”*
I will discuss developmental and social learning aspects of two tool-using behaviors in the community of chimpanzees living at Bossou, Guinea: the use of a pair of stones to crack open hard-shelled nuts and the use of folded clumps of leaves for drinking water. The extent to which field experiments can shed light on the emergence and maintenance of such community-specific behaviors will also be addressed.

Michio Nakamura     
“Rethinking chimpanzee culture”*
The chimpanzee “mind” can only be reached through their behaviors, and we cannot simply assume that behaviors are belonging to independent agents who try only to fulfill their own demands, as individuals are by nature deeply embedded in their society. In this presentation, I would like to reconsider chimpanzee “culture” as one of the phenomena emerging from their everyday social life. I would then argue the importance of the collective aspects of their sociality in understanding their behaviors and minds.

Masako Myowa-Yamakoshi     
“Understanding human imitation from an evolutionary and developmental perspective”*
Recent evidence for “neonatal imitation” in chimpanzees suggests the evolutionary root of the imitative ability of humans. On the other hand, there appears to be a substantial difference in the degree to which humans and chimpanzees imitate whole-body actions. We propose a model of imitation illustrating that human and chimpanzees differ in the way they process visual-motor information. A basic difference in visual-motor information processing may be at the core of the difference in the higher social-cognitive abilities of humans and chimpanzees.

Duane Rumbaugh     
"The Intelligence of Apes Relative to Other Rational Beings"
The capacity of apes to learn the referential meanings of arbitrary symbols and to use those symbols for adaptive use in two-way communication and for meeting novel challenges is substantially greater than for any other primate species other than our own.  The contributions of brain evolution, protracted infant development, and the highly significant roles of significant social models through observational learning to this capacity will be discussed.  This discussion will focus upon a new theory of learning and behavior based on the salience of stimulus events will be considered.  That theory is intended to help us understand how it is that animals quite frequently learn far more than what can be accounted for on the basis of specific training with conventional reinforcement and also how and why individual differences prevail among apes.

Katie Slocombe     
“The mediating role of chimpanzee vocalizations”*
This presentation will examine the role vocalizations play in mediating social relationships and providing listening individuals information about ongoing social interactions. Specifically, it will focus on scream calls given during agonistic interactions and rough grunts given during feeding events.

Michael Tomasello     
“Chimpanzee helping and cooperation”
I review recent studies from our laboratory on how chimpanzees (1) help others achieve their goals and (2) cooperate with others in achieving their goals.  Possible limitations in these skills will be highlighted through comparisons to human children.

Ben Beck     
“Ape orphans: Welfare, conservation, and ethics”
Habitat conversion and commercial hunting have resulted in a glut of young great ape “orphans” (or “refugees”) which, if they are lucky, end up in well-run range country sanctuaries. There are currently more great apes in sanctuaries than in all of the world’s zoos, and their highly evolved cognitive abilities present unique welfare and ethical challenges. Sanctuary mangers, themselves dedicated and ethical professionals, must choose from a handful of often-unrealistic or ethically complicated options for the future of their long-lived apes, while facing financial uncertainties, skepticism from the conservation community, international guidelines and unrelenting responsibility for a population of needy apes that grows daily. We will consider these issues from a perspective of conservation action and from a perspective of the rights of beings with personhood.

Brian Hare     
“A comparison of cooperative problem-solving abilities in chimpanzees and bonobos”
We compared the cooperative problem-solving abilities of chimpanzees and bonobos. When two subjects were confronted with a tray of out-of-reach, sharable food, both species were skillful at spontaneously pulling a rope simultaneously to obtain the food. When two subjects were again placed in the same situation, except the food was no longer sharable, bonobos showed more skill at solving the task. These results support the hypothesis that flexibility in cooperative problem solving is relative to different levels of emotional reactivity while illustrating the value of African sanctuaries for non-invasive research.

William McGrew     
“New battlefronts in the animal culture wars”
Cultural primatology has passed from the natural history stage to the ethnographic stage, and ethnological analyses are now emerging. These advances yield new or enhanced debates on various topics: relative determinants of cultural expression, highlighting the false dichotomy of environmental versus social factors; a plethora of operational versus theoretical definitions of cultural phenomena, including semantic gamesmanship; utility of referential versus conceptual modelling; uneasy comparisons with sociocultural anthropology on the one hand and social learning in non-primates on the other. These issues will be illustrated with examples of recent behavioral primatological findings, especially on wild chimpanzees.

Roman Wittig     
"Decision-making’ during conflicts in wild chimpanzees"
Aggression has a disruptive effect on the relationship between opponents. Group-living animals, therefore, face a dilemma – they cooperate with the same individuals that they compete with over resources. Chimpanzees employ a large variety of strategies during which they seem to weigh advantages against disadvantages. They are thought to go through a "decision-making" process that is more likely to produce an advantageous outcome in competitive situations. I will present data on the chimpanzees of the Taï National Park, Côte d’Ivoire, to point out under which conditions chimpanzees avoid aggression, how they maximise benefits and how they deal with the disruptive effects of aggression. 

John Mitani     
"Chimpanzee minds in nature: Lessons from Ngogo"
Understanding the minds of chimpanzees requires information about the kinds of problems they face and must solve in the real world. The fission-fusion nature of chimpanzee society demands that they navigate an ever-changing social world. To survive and reproduce within this labile society, male chimpanzees cooperate in interactions that take place both within and between communities. Cooperative behavior, involving the reciprocal exchange of behaviors that are both similar and different in kind, is likely to place heavy demands on the mental scorekeeping abilities of chimpanzees. In this talk, I will use results of my long-term field research conducted at Ngogo, Kibale National Park, Uganda, to illustrate some of the critical social and ecological problems that confront wild chimpanzees. 

Ian C. Gilby     
"Cooperative hunting in chimpanzees: lessons from other social predators"
Cooperation is thought to have played a prominent role in human evolution. Thus, chimpanzee behavior is of particular interest to those seeking an understanding of the biological roots of human cooperation. Hunting and meat sharing are frequently cited as prime examples of chimpanzee cooperation, yet there is considerable controversy over the extent to which this is true. Here, I review chimpanzee hunting data from the major long-term field sites, including recent data from Gombe and Kanyawara. I frame the discussion in light of what is known about obligate social carnivores. While the conclusion is unlikely to be definitive, one goal of this exercise is to identify the variables critical to an ongoing examination of cooperative hunting across different study sites and species.

Steve Ross      

"How cognitive studies help shape our obligation for the ethical care of chimpanzees"

Historically, chimpanzees have been subjects for a broad range of cognitive and problem-solving studies, and we have continuously looked to understand the similarities and differences between chimpanzees and our own species. Recent studies of their cognitive capabilities have forced many to rethink and perhaps better appreciate our closest living genetic relatives; they have also led us to reevaluate the way we care for chimpanzees in a captive environment. I will discuss the ways that behavioral and cognitive advances have shaped contemporary ape management and advocate for a continuation of recent trends to provide better and more stimulating environments for chimpanzees in settings ranging from biomedical facilities to sanctuaries and zoological parks.

Elizabeth Lonsdorf     

"Chimpanzee mind, behavior and conservation"

Chimpanzees are our closest living relatives, sharing most of our genetic code and many similarities in anatomy, physiology and behavior. These apes have the capacity to make and use tools as humans do, have strong family bonds like humans and have population-specific behaviors similar to human cultures. But populations of chimpanzees are in dramatic decline due to hunting for bushmeat, loss of habitat and the varied risks of small, isolated populations. Recognizing and understanding the complexities of these threats is the first step in conserving the world’s wild chimpanzee populations. Mitigating these risks takes a deeper understanding of the chimpanzee mind. In this talk, I will review current chimpanzee conservation issues and provide examples of how understanding the chimpanzee mind impacts conservation.

Josep Call      

“Causal knowledge and planning in ape tool use”

It has been suggested that chimpanzees display serious limitations in causal knowledge underlying tool-use. Instead of focusing on the properties of different tools (e.g., rigidity) or the nature of the obstacles that they face, it has been suggested that subjects learn to use certain heuristics to solve problems. Moreover, numerous theorists have suggested that planning skills in nonhuman animals are restricted to the immediate future—individuals perform actions for their immediate consequences to satisfy current needs, not future ones. In this talk I will present recent evidence challenging these positions—at least in their extreme versions.