Abstract: The ability to act on information flexibly is one of the cornerstones of intelligent behavior. As particularly informative example, tool-oriented behavior has been investigated to determine to which extent nonhuman animals understand means-end relations, object affordances, and have specific motor skills. Even planning with foresight, goal-directed problem solving and immediate causal inference have been a focus of research. However, these cognitive abilities may not be restricted to tool-using animals but may be found also in animals that show high levels of curiosity, object exploration and manipulation, and extractive foraging behavior. The kea, a New Zealand parrot, is a particularly good example. We here review findings from laboratory experiments and field observations of keas revealing surprising cognitive capacities in the physical domain. In an experiment with captive keas, the success rate of individuals that were allowed to observe a trained conspecific was significantly higher than that of naive control subjects due to their acquisition of some functional understanding of the task through observation. In a further experiment using the string-pulling task, a well-probed test for means-end comprehension, we found the keas finding an immediate solution that could not be improved upon in nine further trials. We interpreted their performance as insightful in the sense of being sensitive of the relevant functional properties of the task and thereby producing a new adaptive response without trial-and-error learning. Together, these findings contribute to the ongoing debate on the distribution of higher cognitive skills in the animal kingdom by showing high levels of sensorimotor intelligence in animals that do not use tools. In conclusion, we suggest that the 'Technical intelligence hypothesis' (Byrne, Machiavellian intelligence II: extensions and evaluations, pp 289-211, 1997), which has been proposed to explain the origin of the ape/monkey grade-shift in intelligence by a selection pressure upon an increased efficiency in foraging behavior, should be extended, that is, applied to some birds as well.

Abstract: Referential communication occurs when a sender elaborates its gestures to direct the attention of a recipient to its role in pursuit of the desired goal, e.g. by pointing or showing an object, thereby informing the recipient what it wants. If the gesture is successful, the sender and the recipient focus their attention simultaneously on a third entity, the target. Here we investigated the ability of domestic horses (Equus caballus) to communicate referentially with a human observer about the location of a desired target, a bucket of food out of reach. In order to test six operational criteria of referential communication, we manipulated the recipient’s (experimenter) attentional state in four experimental conditions: frontally oriented, backward oriented, walking away from the arena and frontally oriented with other helpers present in the arena. The rate of gaze alternation was higher in the frontally oriented condition than in all the others. The horses appeared to use both indicative (pointing) and non-indicative (nods and shakes) head gestures in the relevant test conditions. Horses also elaborated their communication by switching from a visual to a tactile signal and demonstrated perseverance in their communication. The results of the tests revealed that horses used referential gestures to manipulate the attention of a human recipient so to obtain an unreachable resource. These are the first such findings in an ungulate species.