Gaze following: A socio-cognitive skill rooted in deep time

Abstract

Social gaze has received much attention in social cognition research in both human and non-human animals. Gaze following appears to be a central skill for acquiring social information, such as the location of food and predators, but can also draw attention to important social interactions, which in turn promotes the evolution of more complex socio-cognitive processes such as theory of mind and social learning. In the past decades, a large number of studies has been conducted in this field introducing differing methodologies. Thereby, various factors influencing the results of gaze following experiments have been identified. This review provides an overview of the advances in the study of gaze following, but also highlights some limitations within the research area. The majority of gaze following studies on animals have focused on primates and canids, which limits evolutionary interpretations to only a few and closely related evolutionary lineages. This review incorporates new insights gained from previously understudied taxa, such as fishes, reptiles, and birds, but it will also provide a brief outline of mammal studies. We propose that the foundations of gaze following emerged early in evolutionary history. Basic, reflexive co-orienting responses might have already evolved in fishes, which would explain the ubiquity of gaze following seen in the amniotes. More complex skills, such as geometrical gaze following and the ability to form social predictions based on gaze, seem to have evolved separately at least two times and appear to be correlated with growing complexity in brain anatomy such as increased numbers of brain neurons. However, more studies on different taxa in key phylogenetic positions are needed to better understand the evolutionary history of this fundamental socio-cognitive skill.

How smart wasT. rex? Testing claims of exceptional cognition in dinosaurs and the application of neuron count estimates in palaeontological research

“…One further way of inferring cognitive traits in dinosaurs is by comparatively studying relevant behavioral phenomena in living crocodilians and birds, the groups that form their extant phylogenetic bracket. While such approaches are starting to gain pace (Zeiträg et al, 2023), we are not aware that ethological research could so far identify shared physical or social cognitive skills in crocodilians and birds that have not also been found in turtles and squamates (in case such comparative data is indeed available - Zeiträg et al, 2022; Font et al, 2023). Thus, the behavioral resolution of such approaches appears limited thus far.…”

Gaze following in Archosauria—Alligators and palaeognath birds suggest dinosaur origin of visual perspective taking

“…That geometrical gaze following was shown by all bird species in our study, indicates that it should be within the repertoire of all birds (unless lost secondarily), given that the species studied represent some of the neurocognitively most conserved taxa. Previously, geometrical gaze following in birds has only been identified in two corvid species, common ravens (Corvus corax) and rooks (Corvus frugilegus) (5,37), and in one other songbird, the European starling (Sturnus vulgaris) (6). On the other hand, only one other study on birds has investigated geometrical gaze following.…”

The use of gaze to study cognition: limitations, solutions, and applications to animal welfare

“…Subsequently, as research has embraced other taxonomic groups, interpretation has become more nuanced. Currently it is accepted that sensitivity to gaze in conspecifics (or human carers) and gaze following in general, can be innate and reflexive, and show a developmental trajectory ( Schloegl et al, 2007 ; Zeiträg et al, 2022 ). Differentiation amongst these interpretations depends upon the experimental paradigm, but variation in methodologies has also made interspecific comparisons difficult ( Zeiträg et al, 2022 ).…”

“…Currently it is accepted that sensitivity to gaze in conspecifics (or human carers) and gaze following in general, can be innate and reflexive, and show a developmental trajectory ( Schloegl et al, 2007 ; Zeiträg et al, 2022 ). Differentiation amongst these interpretations depends upon the experimental paradigm, but variation in methodologies has also made interspecific comparisons difficult ( Zeiträg et al, 2022 ). In any case, gaze following appears to serve different functions across different species, varying form reflexive responses to visual perspective taking; it is therefore species-specific with respect to interpretation across a wide range of taxonomic groups ( van Rooijen, 2010 ; Wilkinson et al, 2010 ; Leliveld et al, 2013 ; Davidson and Clayton, 2016 ).…”