Selection pressures due to parasitism play an important role in driving the evolution oflife history traits of birds in general and of behaviour at the nest in particular. Eggshellbacterial load has been shown to predict hatching failure (i.e. the probability of embryoinfection) but the relationships between the bacterial environment of the nest and lifehistory characteristics of birds remain poorly investigated. We explored interspecific variation in eggshell bacterial load of mesophilic bacteria, Enterococcus spp., Staphylococcusspp. and Enterobacteriaceae groups across 24 bird species and assessed whether bacterialload is associated with breeding traits. Interspecific variation was much higher than intraspecific variation for all measures of bacterial load even after controlling for annual variation. Thus, we were able to assess the correlation between bacterial communitycharacteristics and life history traits. After correcting for phylogenetic effects, we foundthat nest type, the use of feathers or plants as lining material, and incubation behaviourexplained a significant proportion of the variance in bacterial communities on eggshells.The strength of these associations depended on study year, suggesting an important roleof environmental conditions for eggshell bacterial load or community. Overall, theseresults suggest that bacteria on eggshells are associated with bird species traits, probablybecause birds are mediating the deleterious effect of eggshell microbes through behavioural traits that modify bacterial load.
Peralta-Sánchez et al. (Tue,) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: