2026/01/21 by Lisandrina Mari, Anna E. Hughes, Jolyon Troscianko +4 · 1 voice · 2 citations
Agricultural and Biological Sciences · Biochemistry, Genetics and Molecular Biology · Environmental Science · #Animal Behavior and Reproduction #Animal Vocal Communication and Behavior #Avian clutch size #Avian ecology and behavior #Barn #Brood #Cooperative breeding #Mechanism (biology) #Nest (protein structural motif) #Population
paper · doi:10.1098/rsbl.2025.0615
published in Biology Letters 22(1) (Royal Society)
openalex publication_date 2026/01/21 · openalex created_date 2026/01/22 · openalex updated_date 2026/07/31
Recognizing one's own eggs is crucial for birds, especially for hosts of brood parasites that must identify and reject different-looking parasitic eggs. While birds seem to possess a 'template image' of their eggs, whether it is innate or refined over time remains unclear. We addressed this question by experimentally inserting either artificial mimetic eggs (ME) or non-mimetic eggs (NME) into the nests of barn swallows (Hirundo rustica) during the pre-laying stage. We harnessed the potential of our individually marked population to perform a unique comparison between naive first-time breeders and experienced females, as well as females with 'old' (from a previous season) and 'recent' (from the previous breeding attempt within the same season) experience, allowing us to investigate the role of memory. We found that neither naive nor experienced females ejected NME more often than ME, suggesting that the template image does not play a primary role in egg recognition. Instead, awareness of own egg-laying might be the crucial mechanism at play, facilitating nest sanitation behaviour. Lastly, we provide the first evidence that this mechanism improves with recent breeding experience.