Sensitivity to geometry in humans and other animals

Abstract

Geometry can be defined as the mathematical formalization of space. Amongst all theories of geometry, Euclidean geometry is considered the most intuitive of all for humans. The reason for this, it has been argued, is that humans (and maybe other animals) spontaneously categorize geometric objects based on their Euclidean properties. In this paper, I briefly review the evidence suggesting that humans and other animals are sensitive to objects' geometric features. I further address the question whether Euclidean principles underlie humans' and other animals' sensitivity to geometry and if not, whether other principles can better account for animals’ categorization of geometric objects. The conclusion of the paper is that animals, including humans, do not spontaneously categorize geometric objects based on their Euclidean properties; however they can learn or be probed to do so. When this is not the case, other non-Euclidean properties, e.g., objects’ topological properties or physical properties, seem to be relevant both for human and nonhuman animals. Humans, however, seem to be special in their ability to analyse objects in terms of more abstract Euclidean concepts.