The Comparative Psychology of Intelligence: Some Thirty Years Later.

After re-reading Macphail's (1987) essay "The Comparative Psychology of Intelligence" with all the associated commentaries, I was struck by how contemporary many of the arguments and counter-arguments still appear. Of course, we now know much more about the abilities of many more species (including their neurobiology) and fewer researchers currently favor explanations of behavior based solely on associative processes; however, the role of contextual variables in comparative psychology still remains cloudy. I discuss these issues briefly. Given my research interests involving the cognitive and communicative abilities of Grey parrots, the one aspect of the original article upon which I feel I can comment in depth involves Macphail's claims about the importance of language-and specifically syntax-in problem-solving and thus in placing humans above all other creatures. Granted, no other species has (or in my opinion is likely ever to acquire) everything that goes into what is considered "human language." Nevertheless, several other species have acquired symbolic representation, and considerable information now exists upon which to base an argument that such acquisition by itself enables more complex and "human-like" cognitive processes. Such processes may form the basis of the kind of intelligence that is measured-not surprisingly-with human-based tasks, including the use of such representations as a means to directly query non-human subjects in ways not unlike those used with young children.

Revisited: Pigeons Have Much Cognitive Behavior in Common With Humans.

The hypothesis proposed by Macphail (1987) is that differences in intelligent behavior thought to distinguish different species were likely attributed to differences in the context of the tasks being used. Once one corrects for differences in sensory input, motor output, and incentive, it is likely that all vertebrate animals have comparable intellectual abilities. In the present article I suggest a number of tests of this hypothesis with pigeons. In each case, the evidence suggests that either there is evidence for the cognitive behavior, or the pigeons suffer from biases similar to those of humans. Thus, Macphail's hypothesis offers a challenge to researchers to find the appropriate conditions to bring out in the animal the cognitive ability being tested.

Modelling the evolution of cognitive styles.

BACKGROUND: Individuals consistently differ in behaviour, exhibiting so-called personalities. In many species, individuals differ also in their cognitive abilities. When personalities and cognitive abilities occur in distinct combinations, they can be described as 'cognitive styles'. Both empirical and theoretical investigations produced contradicting or mixed results regarding the complex interplay between cognitive styles and environmental conditions. RESULTS: Here we use individual-based simulations to show that, under just slightly different environmental conditions, different cognitive styles exist and under a variety of conditions, can also co-exist. Co-existences are based on individual specialization on different resources, or, more generally speaking, on individuals adopting different niches or microhabitats. CONCLUSIONS: The results presented here suggest that in many species, individuals of the same population may adopt different cognitive styles. Thereby the present study may help to explain the variety of styles described in previous studies and why different, sometimes contradicting, results have been found under similar conditions.

What can associative learning do for planning?

There is a new associative learning paradox. The power of associative learning for producing flexible behaviour in non-human animals is downplayed or ignored by researchers in animal cognition, whereas artificial intelligence research shows that associative learning models can beat humans in chess. One phenomenon in which associative learning often is ruled out as an explanation for animal behaviour is flexible planning. However, planning studies have been criticized and questions have been raised regarding both methodological validity and interpretations of results. Due to the power of associative learning and the uncertainty of what causes planning behaviour in non-human animals, I explored what associative learning can do for planning. A previously published sequence learning model which combines Pavlovian and instrumental conditioning was used to simulate two planning studies, namely Mulcahy & Call 2006 'Apes save tools for future use.' Science 312, 1038-1040 and Kabadayi & Osvath 2017 'Ravens parallel great apes in flexible planning for tool-use and bartering.' Science 357, 202-204. Simulations show that behaviour matching current definitions of flexible planning can emerge through associative learning. Through conditioned reinforcement, the learning model gives rise to planning behaviour by learning that a behaviour towards a current stimulus will produce high value food at a later stage; it can make decisions about future states not within current sensory scope. The simulations tracked key patterns both between and within studies. It is concluded that one cannot rule out that these studies of flexible planning in apes and corvids can be completely accounted for by associative learning. Future empirical studies of flexible planning in non-human animals can benefit from theoretical developments within artificial intelligence and animal learning.

Measuring and modeling for the assessment of the genetic background behind cognitive processes in donkeys.

New productive niches can offer new commercial perspectives linked to donkeys' products and human therapeutic or leisure applications. However, no assessment for selection criteria has been carried out yet. First, we assessed the animal inherent features and environmental factors that may potentially influence several cognitive processes in donkeys. Then, we aimed at describing a practical methodology to quantify such cognitive processes, seeking their inclusion in breeding and conservation programmes, through a multifactorial linear model. Sixteen cognitive process-related traits were scored on a problem-solving test in a sample of 300 Andalusian donkeys for three consecutive years from 2013 to 2015. The linear model assessed the influence and interactions of four environmental factors, sex as an animal-inherent factor, age as a covariable, and the interactions between these factors. Analyses of variance were performed with GLM procedure of SPSS Statistics for Windows, Version 24.0 software to assess the relative importance of each factor. All traits were significantly (P<0.05) affected by all factors in the model except for sex that was not significant for some of the cognitive processes, and stimulus which was not significant (P<0.05) for all of them except for the coping style related ones. The interaction between all factors within the model was non-significant (P<0.05) for almost all cognitive processes. The development of complex multifactorial models to study cognitive processes may counteract the inherent variability in behavior genetics and the estimation and prediction of related breeding parameters, key for the implementation of successful conservation programmes in apparently functionally misplaced endangered breeds.

Between biomedical and psychological experiments: The unexpected connections between the Pasteur Institutes and the study of animal mind in the second quarter of twentieth-century France.

This article explores the unexpected connections between the Pasteur Institute in French Guinea and the study of animal mind in early twentieth century France. At a time when the study of animal intelligence was thriving in France and elsewhere, apes were appealing research subjects both in psychological and biomedical studies. Drawing on two case studies (Guillaume/Meyerson and Urbain), and then, on someone responding negatively to those connections, Thétard, this article shows how the long reach of biomedicine (linked to the prestige of Bernard and Pasteur) impinged on French biology and played a role in the tortuous, if not unsuccessful fate of animal psychology in France in the second quarter of the twentieth century. It shows how attempts to use apes (and other zoo animals) to yield new insights on animal psychology faced heavy restrictions or experienced false starts, and examines the reasons why animal psychology could not properly thrive at that time in France. Beyond the supremacy of biomedical interests over psychological ones, this article additionally explains that some individuals used animal behaviour studies as steppingstones in careers in which they proceeded on to other topics. Finally, it illustrates the tension between non-academic and academic people at a time when animal psychology was trying to acquire scientific legitimacy, and also highlights the difficulties attached to the scientific study of animals in a multipurpose and hybrid environment such as the early twentieth century Parisian zoo and also the Pasteur Institute of French Guinea.

Animal memory: A review of delayed matching-to-sample data.

We performed a meta-analysis of over 90 data sets from delayed matching-to-sample (DMTS) studies with 25 species (birds, mammals, and bees). In DMTS, a sample stimulus is first presented and then removed. After a delay, two (or more) comparison stimuli are presented, and the subject is rewarded for choosing the one matching the sample. We used data on performance vs. delay length to estimate two parameters informative of working memory abilities: the maximum performance possible with no delay (comparison stimuli presented as soon as the sample is removed), and the rate of performance decay as the delay is lengthened (related to memory span). We conclude that there is little evidence that zero-delay performance varies between these species. There is evidence that pigeons do not perform as well as mammals at longer delay intervals. Pigeons, however, are the only extensively studied bird, and we cannot exclude that other birds may be able to bridge as long a delay as mammals. Extensive training may improve memory, although the data are open to other interpretations. Overall, DMTS studies suggest memory spans ranging from a few seconds to several minutes. We suggest that observations of animals exhibiting much longer memory spans (days to months) can be explained in terms of specialized memory systems that deal with specific, biologically significant information, such as food caches. Events that do not trigger these systems, on the other hand, appear to be remembered for only a short time. This article is part of a Special Issue entitled: In Honor of Jerry Hogan.

Resolução de problema por macacos-prego selvagens (Sapajus libidinosus) de duas populações com diferentes repertórios de uso de ferramentas / Problem solving by wild bearded capuchin monkeys (Sapajus libidinosus) from two populations with different tool-use repertoires

Os macacos-prego (Sapajus libidinosus) são reconhecidos pela flexibilidade comportamental, incluindo o uso de ferramentas na natureza. Admite-se que o contexto social contribua para aprendizagem individual de comportamentos flexíveis pelos macacos-prego. A influência social sobre a aprendizagem é considerada como uma característica básica da cultura. As diferenças observadas no conjunto de ferramentas entre populações naturais de macacos-prego sugerem a existência de tradições nestes primatas. Em um experimento em campo apresentamos aos macacos de duas populações, que diferiam acerca de suas tradições instrumentais, um problema que exigia o uso de sondas para obter melaço dentro de uma caixa-problema. Investigamos se os macacos destas populações abordariam o problema de acordo com as respectivas tradições instrumentais. As populações investigadas habitam diferentes regiões do Estado do Piauí, interior do nordeste brasileiro, e distam aproximadamente 350Km entre si, sendo a paisagem ecológica tipicamente marcada pelo bioma cerrado/caatinga. Os macacos da população da Fazenda Boa Vista (FBV) são proficientes no uso de percutores durante o processamento de cocos-de-palmeiras e frutos secos de caju. Apesar de quase uma década de observação sistemática nesta população, não foi observado o uso de outras ferramentas por estes macacos. Os macacos da população do Parque Nacional da Serra da Capivara (PNSC), por sua vez, utilizam habitualmente um conjunto diversificado de ferramentas, incluindo o uso de percutores e sondas. Nossa hipótese predisse que os macacos da população PNSC (grupo Pedra Furada) resolveriam o problema em menor tempo e apresentariam melhor desempenho, enquanto os macacos da FBV (grupo Chicão) não utilizariam sondas durante as tentativas de obter o melaço, ou demandariam maior tempo até alcançarem o sucesso no problema, e esperávamos pudessem percutir pedras contra a caixa.(AU)

Capuchin monkeys (Sapajus libidinosus) have been recognized by their behavioral flexibility, including tool-using in nature. Currently, its acknowledged that social context contributes to individual learning of that flexible behavior by capuchin monkeys. The social influence on learning is the most basic feature of culture. The differences observed in tool kit exhibited in natural populations of capuchin monkeys suggest the existence of culture in these New World primates. We ran a field experiment in two populations of capuchin monkeys which differed in their tool use traditions. In this experiment we presented a problem that required probe-tool using to reach molasses available inside the problem-box. We investigated whether monkeys from these populations approached the problem according to their respectively tool use traditions. Both populations inhabit different regions in the State of Piauí, in Northeastern Brazil, and are about 350Km apart. The ecological landscapes of these research sites are the the savana-like cerrado and caatinga biomes. Monkeys from Fazenda Boa Vista (FBV) are proficient pounding-tool users that habitually use stones as hammers to crack open palm-nuts and dry cashew fruit. After almost a decade of systematic observations, no other form of tool use was observed in this population. Capuchin monkeys from Parque Nacional da Serra da Capivara (PNSC), on the other hand, have been observed using a much broader tool-kit, including pounding tools, as well as probing tools during their foraging activities. Our hypothesis predicted that capuchins from the PNSC population (Pedra Furada group) would take less time to solve the task than capuchins from FBV (Chicão group), and also that they would perform better in comparison to that group. We also expected that Chicão group would pound stones against the problem box.(AU)