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Updated: Oct 6, 2026

Probing the Limits of Egg Recognition Using Egg Rejection Experiments Along Phenotypic Gradients
Published on: August 22, 2018
Discrimination between individual humans by domestic fowl (Gallus gallus domesticus)
Abstract:
1. We demonstrate that Barred-Rock and Isa-Brown hens can discriminate between the presence of 2 different humans and use this information as a cue for whether or not to make an operant response. 2. This demonstration in domestic fowl, the first of its kind in any avian subject, is consistent with a growing body of evidence that many species, including agricultural animals, are surprisingly adept at differentiating between humans. 3. Such a discriminative ability carries considerable implications for issues related to husbandry, production and welfare.
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