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Image scoring in great apes
'Image scoring' occurs when person A monitors the giving behaviour of person B towards person C. We tested for 'image scoring' in chimpanzees, bonobos, gorillas, and orangutans. Subjects passivelyExpand
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Kleptoparasitism in gulls Laridae at an urban and a coastal foraging environment: an assessment of ecological predictors
ABSTRACT Capsule: Kleptoparasitism in gulls occurred at a greater rate at an urban compared with a coastal site. Population density and prey size predicted the rate of kleptoparasitism at the urbanExpand
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How do you measure pleasure? A discussion about intrinsic costs and benefits in primate allogrooming
Social grooming is an important element of social life in terrestrial primates, inducing the putative benefits of β-endorphin stimulation and group harmony and cohesion. Implicit in many analyses ofExpand
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Reputations and polyadic interactions among great apes
‘Reputation’ refers to information about the past behaviour of others, learnable either by direct observation, eavesdropping, or gossip. Reputations are thought to play a key role among humanExpand
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Mood, expertise, analogy, and ritual: an experiment using the five-disk Tower of Hanoi
We used game playing as a proxy for religious ritual in a study of the differential effects of euphoric and dysphoric mood – focusing on expertise and analogical reasoning. Previous researchExpand
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Sinuosity and the Affect Grid: A Method for Adjusting Repeated Mood Scores
Sinuosity is a measure of how much a travelled pathway deviates from a straight line. In this paper, sinuosity is applied to the measurement of mood. The Affect Grid is a mood scale that requiresExpand
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Precise time-matching in chimpanzee allogrooming does not occur after a short delay
Allogrooming is a key aspect of chimpanzee sociality and many studies have investigated the role of reciprocity in a biological market. One theoretical form of reciprocity is time-matching, whereExpand
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What is Counterintuitive? Religious Cognition and Natural Expectation
What is ‘counterintuitive’? There is general agreement that it refers to a violation of previously held knowledge, but the precise definition seems to vary with every author and study. The aim ofExpand
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An ‘indirect reputation’ experiment in four great ape species
Reputation is defined as knowledge of a person’s typical behaviour based on that person’s past behaviour. Indirect reputation refers to knowledge gained from observing events between third parties.Expand
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Economic drivers of biological complexity
We review these problems from an economic perspective, and highlight how ideas from economics can help us to better understand how the benefits of social interactions arise, how they are sustained, and how they affect the underlying social dilemmas. Expand
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