Maculation on avian eggshells has the potential to serve as an identity signal, and this information may help females recognize their eggs/nest or reject foreign eggs laid by hetero‐ or conspecific brood parasites. Recognizing eggs could be adaptive in cases where birds nest in dense colonies, as reports of conspecific brood parasitism are over‐represented in colony‐nesting species. We utilized the variation in breeding biology (solitary vs. colonial breeding) and eggshell phenotype in swallows and martins (Hirundinidae) to test for correlated evolution between these traits, while also accounting for nest type, as maculation may camouflage eggs in open‐cup nests. We found that maculated eggs were more likely to be laid by species that breed socially and build open‐cup nests where maculation would be more visible than in dark cavity nests.
Many animals breed colonially, often in dense clusters, representing a complex social environment with cognitive demands that could ultimately impact individual fitness. However, the effects of social breeding on the evolution of cognitive processes remain largely unknown. We tested the hypothesis that facultative colonial breeding influences attention and decision-making. Barn swallows (
- NSF-PAR ID:
- 10493670
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Animal Cognition
- Volume:
- 27
- Issue:
- 1
- ISSN:
- 1435-9456
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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