Slides of conspecifics as representatives of real animals in laying hens (Gallus domesticus).

Four 18-week-old Ross Brown laying hens were trained to discriminate between slides of the heads of familiar or unfamiliar conspecifics. Those individuals trained to discriminate between slides of familiar conspecifics failed to show a better discrimination ability when presented with slides of novel views of these object birds, as compared with subjects trained to discriminate between slides of unfamiliar conspecifics and presented with similar corresponding novel views. There was also no evidence that subjects learnt to discriminate slides of familiar conspecifics more quickly than slides of unfamiliar conspecifics. It was concluded that there was no evidence that the hens perceived the slides presented as representations of their group members.