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A Modified Mirror Test as a Visual Guide for the Self-awareness Trait in Wild Antarctica Penguins, Pygoscelis adeliae
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Carrion crows (Corvus corone corone) fail the mirror mark test yet again.

Katharina F Brecht1, Jan Müller1, Andreas Nieder1

  • 1Institute of Neurobiology.

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Carrion crows did not pass the mirror mark test, failing to show self-recognition. This research adds to the ongoing debate about mirror self-recognition in corvids, particularly crows.

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Area of Science:

  • Comparative psychology
  • Animal cognition
  • Avian behavior

Background:

  • The mirror mark test assesses an animal's capacity for self-recognition.
  • While some corvids like magpies and Indian house crows have passed, results in other corvids remain inconclusive.

Purpose of the Study:

  • To investigate whether carrion crows (Corvus corone corone) exhibit self-recognition using the mirror mark test.
  • To contribute to the understanding of mirror self-recognition in avian species.

Main Methods:

  • Twelve carrion crows were subjected to the mirror mark test.
  • Mark-directed behaviors were compared between mirror conditions and control conditions.

Main Results:

  • Carrion crows did not show a significant increase in mark-directed behavior in the presence of the mirror.
  • Observed mark-directed behaviors were infrequent and interpreted within broader self-directed behaviors.
  • Crows demonstrated motivation to interact with the mark when directly visible without a mirror.

Conclusions:

  • Carrion crows failed the mirror mark test, indicating a lack of self-recognition in this context.
  • The findings align with previous studies showing failures in corvids, suggesting controversy surrounding mirror self-recognition in these birds.