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Ravens attribute visual access to unseen competitors.

Thomas Bugnyar1,2, Stephan A Reber1,2, Cameron Buckner3

  • 1Department of Cognitive Biology, University of Vienna, Althanstrasse 14, 1090 Wien, Austria.

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Ravens guard caches when they hear others if a peephole is open, suggesting they understand the possibility of being seen. This indicates advanced cognitive abilities beyond simple associative learning.

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Area of Science:

  • Cognitive Ethology
  • Animal Behavior
  • Comparative Psychology

Background:

  • Previous research suggested primates and corvids have a basic Theory of Mind (ToM).
  • These findings were debated due to potential confounds, such as the conspecific's line of gaze acting as a cue.
  • A clear understanding of whether animals can infer visual access remains elusive.

Purpose of the Study:

  • To investigate whether ravens (Corvus corax) can infer visual access in the absence of direct visual cues.
  • To determine if ravens adjust their caching behavior based on the potential for being observed.

Main Methods:

  • Experiments were conducted with ravens guarding cached food items.
  • The presence or absence of a peephole (allowing potential visual access) was manipulated.
  • The auditory presence of conspecifics was introduced while monitoring caching behavior.

Main Results:

  • Ravens exhibited increased vigilance and guarding behavior when conspecifics were audibly present and the peephole was open.
  • Guarding behavior was significantly reduced when the peephole was closed, despite the auditory presence of conspecifics.
  • This suggests ravens inferred the possibility of being seen through the open peephole.

Conclusions:

  • Ravens demonstrate an understanding of visual access, inferring the possibility of being observed.
  • These findings provide strong evidence for advanced cognitive abilities in ravens, supporting a Theory of Mind.
  • The study suggests ravens can generalize their own perceptual experiences to understand others' potential viewpoints.