Young domestic chicks spontaneously represent the absence of objects

Elife. 2022 Apr 11:11:e67208. doi: 10.7554/eLife.67208.

Abstract

Absence is a notion that is usually captured by language-related concepts like zero or negation. Whether nonlinguistic creatures encode similar thoughts is an open question, as everyday behavior marked by absence (of food, of social partners) can be explained solely by expecting presence somewhere else. We investigated 8-day-old chicks' looking behavior in response to events violating expectations about the presence or absence of an object. We found different behavioral responses to violations of presence and absence, suggesting distinct underlying mechanisms. Importantly, chicks displayed an avian signature of novelty detection to violations of absence, namely a sex-dependent left-eye-bias. Follow-up experiments excluded accounts that would explain this bias by perceptual mismatch or by representing the object at different locations. These results suggest that the ability to spontaneously form representations about the absence of objects likely belongs to the initial cognitive repertoire of vertebrate species.

Keywords: chicken; domestic chicks; lateralization; looking behavior; neuroscience; object cognition; representing absence.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chickens* / physiology

Grants and funding

The funders had no role in study design, data collection, and interpretation, or the decision to submit the work for publication.