2023/10/25 by Sonja Hillemacher, Sebastian Ocklenburg, Onur Güntürkün +1 · 1 voice · 2 citations
Biochemistry, Genetics and Molecular Biology · Psychology · #Animal Vocal Communication and Behavior #Human-Animal Interaction Studies #Primate Behavior and Ecology
paper · pdf · doi:10.1371/journal.pone.0291416
openalex publication_date 2023/10/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Touching a mark on the own body when seeing this mark in a mirror is regarded as a correlate of self-awareness and seems confined to great apes and a few further species. However, this paradigm often produces false-negative results and possibly dichotomizes a gradual evolutionary transition of self-recognition. We hypothesized that this ability is more widespread if ecologically tested and developed such a procedure for a most unlikely candidate: chickens (Gallus gallus domesticus). Roosters warn conspecifics when seeing an aerial predator, but not when alone. Exploiting this natural behavior, we tested individual roosters alone, with another male, or with a mirror while a hawk's silhouette flew above them. Roosters mainly emitted alarm calls in the presence of another individual but not when alone or seeing themselves in the mirror. In contrast, our birds failed the classic mirror test. Thus, chickens possibly recognize their reflection as their own, strikingly showing how much cognition is ecologically embedded.