Cognitive differences between orang-utan species: a test of the cultural intelligence hypothesis

We also express our gratitude to the following foundations who have financially supported this project: A. H. Schultz Foundation, Paul Schiller Foundation and the Claraz Foundation in Switzerland and Waldemar von Frenckells Foundation, Ella and Georgh Ehrnrooths Foundation, Otto A. Malms Donationsfond, Nordenskiöld Samfundet and Oskar Öflunds Foundation in Finland.Cultural species can-or even prefer to-learn their skills from conspecifics. According to the cultural intelligence hypothesis, selection on underlying mechanisms not only improves this social learning ability but also the asocial (individual) learning ability. Thus, species with systematically richer opportunities to socially acquire knowledge and skills should over time evolve to become more intelligent. We experimentally compared the problem-solving ability of Sumatran orang-utans (Pongo abelii), which are sociable in the wild, with that of the closely related, but more solitary Bornean orang-utans (P. pygmaeus), under the homogeneous environmental conditions provided by zoos. Our results revealed that Sumatrans showed superior innate problem-solving skills to Borneans, and also showed greater inhibition and a more cautious and less rough exploration style. This pattern is consistent with the cultural intelligence hypothesis, which predicts that the more sociable of two sister species experienced stronger selection on cognitive mechanisms underlying learning.Publisher PDFPeer reviewe

Ranosrednjovjekovni sloj episkopalnog kompleksa u Zadru

The episcopal complex in Zadar has buildings dating from several historical periods. In this article the author describes those of early-medieval times, and connects them with social and cultural relations in Dalmatia during the eighth and ninth centuries. An especially interesting feature of the complex is the rotunda of the Holy Trinity (St Donatus), a residential chapel that emerged from two architectural concepts. Its building was part of extensive reconstruction work: a new wing was added to the bishop\u27s palace, a new ci~tern was built in the old diaconicon on the other side of the cathedral, the cathedral presbytery, the site of the first crypt or confessio, was reconstructed, and pastophories were built flanking the apses

Spontaneous innovation of hook-bending and unbending in orangutans (Pongo abelii)

This work was supported by FWF Grants P-29084 and P-29075 to Alice Auersperg and by a uni:docs fellowship of the University of Vienna to Isabelle Laumer.Betty the crow astonished the scientific world as she spontaneously crafted hook-tools from straight wire in order to lift a basket out of vertical tubes. Recently it was suggested that this species’ solution was strongly influenced by predispositions from behavioural routines from habitual hook-tool manufacture. Nevertheless, the task became a paradigm to investigate tool innovation. Considering that young humans had surprising difficulties with the task, it was yet unclear whether the innovation of a hooked tool would be feasible to primates that lacked habitual hook making. We thus tested five captive orangutans in a hook bending and unbending task. Orangutans are habitually tool-using primates that have been reported to use but not craft hooked tools for locomotion in the wild. Two orangutans spontaneously innovated hook tools and four unbent the wire from their first trial on. Pre-experience with ready-made hooks had some effect but did not lead to continuous success. Further subjects improved the hook-design feature when the task required the subjects to bent the hook at a steeper angle. Our results indicate that the ability to represent and manufacture tools according to a current need does not require stereotyped behavioural routines, but can indeed arise innovatively. Furthermore, the present study shows that the capacity for hook tool innovation is not limited to large brained birds within non-human animals.Publisher PDFPeer reviewe

Orangutans (Pongo abelii) make flexible decisions relative to reward quality and tool functionality in a multi-dimensional tool-use task

This work was supported by the University of St Andrews and the Max Planck Institute for Evolutionary Anthropology. Isabelle Laumer was supported by a uni:docs fellowship of the University of Vienna, Alice Auersperg was supported by by FWF grants J 3404-B19 and P 29084, and Thomas Bugnyar by Y366-B17.Making economic decisions in a natural foraging situation that involves the use of tools, may require an animal to consider more levels of relational complexity than merely deciding between an immediate and a delayed food option. We used the same method previously used with Goffin´s cockatoos to investigate the orangutans’ flexibility for making the most profitable decisions when confronted with five different settings that included one or two different apparatuses, two different tools and two food items (one more preferred than the other). We found that orangutans made profitable decisions relative to reward quality, when the task required the subjects to select a tool over an immediately accessible food reward. Furthermore, most subjects were sensitive to work-effort when the immediate and the delayed option (directly accessible by using a tool) led to the same outcome. Most subjects continued to make profitable decisions that required taking into account the tool functionality. In a final multidimensional task design in which subjects had to simultaneously focus on two apparatuses, two reward qualities and two different tools, the orangutans chose the functional tool to access the high quality reward.Publisher PDFPeer reviewe

The plight of the sense-making ape

This is a selective review of the published literature on object-choice tasks, where participants use directional cues to find hidden objects. This literature comprises the efforts of researchers to make sense of the sense-making capacities of our nearest living relatives. This chapter is written to highlight some nonsensical conclusions that frequently emerge from this research. The data suggest that when apes are given approximately the same sense-making opportunities as we provide our children, then they will easily make sense of our social signals. The ubiquity of nonsensical contemporary scientific claims to the effect that humans are essentially--or inherently--more capable than other great apes in the understanding of simple directional cues is, itself, a testament to the power of preconceived ideas on human perception

Orientation toward humans predicts cognitive performance in orang-utans

The authors acknowledge the Swiss National Science Foundation and following foundations who have financially supported this project: A. H. Schultz Foundation, Paul Schiller Foundation and the Claraz Foundation in Switzerland and Waldemar von Frenckells Foundation, Ella and Georgh Ehrnrooths Foundation, Otto A. Malms Donationsfond, Nordenskiöld Samfundet and Oskar Öflunds Foundation in Finland.Non-human animals sometimes show marked intraspecific variation in their cognitive abilities that may reflect variation in external inputs and experience during the developmental period. We examined variation in exploration and cognitive performance on a problem-solving task in a large sample of captive orang-utans (Pongo abelii & P. pygmaeus, N = 103) that had experienced different rearing and housing conditions during ontogeny, including human exposure. In addition to measuring exploration and cognitive performance, we also conducted a set of assays of the subjects’ psychological orientation, including reactions towards an unfamiliar human, summarized in the human orientation index (HOI), and towards novel food and objects. Using generalized linear mixed models we found that the HOI, rather than rearing background, best predicted both exploration and problem-solving success. Our results suggest a cascade of processes: human orientation was accompanied by a change in motivation towards problem-solving, expressed in reduced neophobia and increased exploration variety, which led to greater experience, and thus eventually to higher performance in the task. We propose that different experiences with humans caused individuals to vary in curiosity and understanding of the physical problem-solving task. We discuss the implications of these findings for comparative studies of cognitive ability.Publisher PDFPeer reviewe

Differences in the Cognitive Skills of Bonobos and Chimpanzees

While bonobos and chimpanzees are both genetically and behaviorally very similar, they also differ in significant ways. Bonobos are more cautious and socially tolerant while chimpanzees are more dependent on extractive foraging, which requires tools. The similarities suggest the two species should be cognitively similar while the behavioral differences predict where the two species should differ cognitively. We compared both species on a wide range of cognitive problems testing their understanding of the physical and social world. Bonobos were more skilled at solving tasks related to theory of mind or an understanding of social causality, while chimpanzees were more skilled at tasks requiring the use of tools and an understanding of physical causality. These species differences support the role of ecological and socio-ecological pressures in shaping cognitive skills over relatively short periods of evolutionary time

Interacting mindreaders

Could interacting mindreaders be in a position to know things which they would be unable to know if they were manifestly passive observers? This paper argues that they could. Mindreading is sometimes reciprocal: the mindreader's target reciprocates by taking the mindreader as a target for mindreading. The paper explains how such reciprocity can significantly narrow the range of possible interpretations of behaviour where mindreaders are, or appear to be, in a position to interact. A consequence is that revisions and extensions are needed to standard theories of the evidential basis of mindreading. The view also has consequences for understanding how abilities to interact combined with comparatively simple forms of mindreading may explain the emergence, in evolution or development, of sophisticated forms of social cognition