Animal pointing: Changing trends and findings from 30 years of research.

Abstract

The past 30 years have witnessed a continued and growing interest in the production and comprehension of manual pointing gestures in nonhuman animals. Captive primates with diverse rearing histories have shown evidence of both pointing production and comprehension, though there certainly are individual and species differences, as well as substantive critiques of how to interpret pointing or "pointing-like" gestures in animals. Early literature primarily addressed basic questions about whether captive apes point, understand pointing, and use the gesture in a way that communicates intent (declarative) rather than motivational states (imperative). Interest in these questions continues, but more recently there has been a dramatic increase in the number of articles examining pointing in a diverse array of species, with an especially large literature on canids. This proliferation of research on pointing and the diversification of species studied has brought new and exciting questions about the evolution of social cognition, and the effects of rearing history and domestication on pointing production and, more prolifically, comprehension. A review of this work is in order. In this article, we examine trends in the literature on pointing in nonhumans. Specifically, we examine publication frequencies of different study species from 1987 to 2016. We also review data on the form and function of pointing, and evidence either supporting or refuting the conclusion that various nonhuman species comprehend the meaning of pointing gestures. (PsycINFO Database Record

The effects of changes in the referential problem space of infants and toddlers (Homo sapiens): Implications for cross-species comparisons.

“…Thus, when presenting similar tasks across representatives of different species, it is important to consider how response requirements or expectations interact with life history stage and pre-experimental life experience, to ensure that organisms are given the best opportunity to display their cognitive competencies; for example, it is well-demonstrated that enculturated apes significantly outperform institutionalised apes in similar experimental contexts (Lyn et al, 2010;Russell et al, 2011; and see, in a different context, arguments by Horowitz, 2003, andThomas, Murphy, Pitt, Rivers, &Leavens, 2008, to the effect that younger humans are not representative of adult humans in some cognitive assays). Thus, because previous cross-species comparisons have generally not controlled for life history stage or task-relevant pre-experimental experience (Clark et al, 2019;Krause et al, 2018;Leavens et al, 2019), and because the present study shows a developmental shift in human children toward a reduced reliance on the use of communication in the presence of a barrier, therefore, we recommend a systematic revision to the OCT that permits both communicative HUMAN REFERENTIAL PROBLEM SPACE 26 and praxic responses. This adjustment will foster best performance to be captured and reduce the existing bias towards false negatives in some testing circumstances.…”

Fifteen ways of looking at a pointing gesture

“…As debates about chimps continue, research on animal pointing has broadened out considerably. Recent studies have examined putative pointing in gorillas, mangabeys, dogs, horses, dolphins, and magpies, among others (Krause, Udell, Leavens, & Skopos, 2018). Such behaviors do not look like canonical index finger pointing, of course-many of these animals do not have fingers.…”

“…A parallel branch of research focuses, not on whether animals naturally point for each other, but on whether they understand human pointing (Krause et al, 2018). The question is more experimentally tractable, permitting tidy designs and clever manipulations; it thus provides a litmus test that can be applied across diverse taxa.…”

“…Beyond primates and dogs, the issue has now been examined in capuchins, sea lions, elephants, bats, pigs, goats, cats and other species, with many studies reporting some degree of understanding (Krause et al, 2018). Importantly, even species that succeed on this task do not necessarily succeed at human-like levels.…”

“…From this still-expanding and sometimes conflicting literature on animal pointing, a few generalizations emerge. For one, interaction with humans over the lifespan correlates with better understanding of human pointing (Krause et al, 2018). Further, animals from diverse habitats and taxa, and with widely different body-plans, behave in ways that steer the attention of their conspecifics; the thorny question is what is going on in these animals' minds when they do this.…”