Alaïs Liénard, Diego Gil, Chantal Poteaux, Raquel Monclús
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引用次数: 0
Abstract
Conspecific brood parasitism (CBP) is an alternative reproductive tactic in egg-laying species, where a female lays her eggs in the nest of a conspecific. In a population of spotless starlings (Sturnus unicolor), we observed that some eggs are ejected from the nest during CBP events. It is unclear whether this ejection is a parasitic strategy (a host egg is ejected) or an anti-parasitism strategy (the parasitic egg is ejected). To clarify this, we genotyped the eggs ejected on the ground and found that 100% of them were parasitic. Egg discrimination might be based on tactile or visual cues, and we hypothesized that egg size could be used by hosts to eject parasitic eggs. We conducted experiments in the field using dummy eggs of varying sizes. The results showed that starlings were more likely to eject eggs if they were smaller than their own eggs. In contrast, no significant pattern of egg ejection was observed for larger eggs. Our results suggest that starlings use egg volume recognition as an anti-parasitism strategy to avoid the costs of parasitism. Whether this is a frequency-dependent strategy is worth further studies.
期刊介绍:
Previously a supplement to Proceedings B, and launched as an independent journal in 2005, Biology Letters is a primarily online, peer-reviewed journal that publishes short, high-quality articles, reviews and opinion pieces from across the biological sciences. The scope of Biology Letters is vast - publishing high-quality research in any area of the biological sciences. However, we have particular strengths in the biology, evolution and ecology of whole organisms. We also publish in other areas of biology, such as molecular ecology and evolution, environmental science, and phylogenetics.