FIELD SEASON 2018
We have successfully completed the field season in 2018. We collected blood samples from 218 individual birds belonging to various bird species during their breeding periods. Samples are currently processed in the laboratory to develop an extensive immunological and oxidative stress database. Samples were collected in various places across the country, including Dobrogea, the Danube Delta and the Carpathian Mountains in order to cover a wide range of habitats and capture birds from a wide taxonomic scale.
SEX-SPECIFIC LIFE HISTORIES AND PHYSIOLOGY OF BIRDS AND MAMMALS
Our research team is focusing on building an extensive database concerning the sex-specific life-histories and physiology of birds and mammals. During the last couple months we have collected physiology and demography data from various bird and mammal species from literature and online resources. Our database covers both wild and captive populations of various animal species and builds on extensive online resources, such as the Zoological Information Management System (ZIMS, a global database of captive animals).
An important paper has been published in the prestigious Ecology Letters about the sexual dimorphism in immune responsiveness in the animal kingdom as evidenced by a meta-analysis.
The article entitled “Sexual dimorphism in immunity across animals: a meta-analysis” can be accessed here.
In animals, sex differences in immunity are proposed to shape variation in infection prevalence and intensity among individuals in a population, with females typically expected to exhibit superior immunity due to life-history trade-offs. We performed a systematic meta-analysis to investigate the magnitude and direction of sex differences in immunity and to identify factors that shape sex-biased immunocompetence. In addition to considering taxonomic and methodological effects as moderators, we assessed age-related effects, which are predicted to occur if sex differences in immunity are due to sex-speciﬁc resource allocation trade-offs with reproduction. In a meta-analysis of 584 effects from 124 studies, we found that females exhibit a signiﬁcantly stronger immune response than do males, but the effect size is relatively small, and became non-signiﬁcant after controlling for phylogeny. Female-biased immunity was more pronounced in adult than immature animals. More recently published studies did not report signiﬁcantly smaller effect sizes. Among taxonomic and methodological subsets of the data, some of the largest effect sizes were in insects,further supporting previous suggestions that testosterone is not the only potential driver of sex differences in immunity. Our ﬁndings challenge the notion of pervasive biases towards female-biased immunity and the role of testosterone in driving these differences.
Immune response, immunity, life-history, sexual dimorphism.