Skip to main content

Research Repository

See what's under the surface

Microparasites and placental invasiveness in eutherian mammals

Capellini, Isabella; Nunn, Charles L.; Barton, Robert A.

Authors

Isabella Capellini

Charles L. Nunn

Robert A. Barton



Contributors

Michelle L. Baker
Editor

Abstract

© 2015 Capellini et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Placental invasiveness - the number of maternal tissue layers separating fetal tissues from maternal blood - is variable across mammalian species. Although this diversity is likely to be functionally important, variation in placental invasiveness remains unexplained. Here we test the hypothesis that increased risk of transplacental transmission of pathogens from the mother to the fetus promotes the evolution of non-invasive placentation, the most likely derived condition in eutherian mammals. Specifically, we predict that non-invasive placentation is associated with increased microparasite species richness relative to more invasive placental types, based on the assumption that higher numbers of microparasites in a population reflects greater risk of transplacental transmission to fetuses. As predicted, higher bacteria species richness is associated with non-invasive placentation. Protozoa species richness, however, shows the opposite pattern. Because invasive placentae facilitate the transfer of maternal antibodies to the fetus, we propose that the ancestral condition of invasive placentation is retained under selection for protection of newborns from higher risk of postnatal protozoan infection. Hence, our findings suggest that a tradeoff exists between protection against bacterial infection prenatally and protozoan infection postnatally. Future studies are needed to investigate how maternal prevalence of infection and the relative pre-versus postnatal risk of fetal infection by different microparasite groups vary among mammalian hosts in relation to placental invasiveness.

Journal Article Type Article
Publication Date Jul 13, 2015
Journal PLoS ONE
Print ISSN 1932-6203
Electronic ISSN 1932-6203
Publisher Public Library of Science
Peer Reviewed Peer Reviewed
Volume 10
Issue 7
Article Number ARTN e0132563
Pages 1-12
Institution Citation Capellini, I., Nunn, C. L., & Barton, R. A. (2015). Microparasites and placental invasiveness in eutherian mammals. PloS one, 10(7), 1-12. https://doi.org/10.1371/journal.pone.0132563
DOI https://doi.org/10.1371/journal.pone.0132563
Keywords Placentation, Species diversity, Invasive species, Parasite evolution, Protozoans, Animal phylogenetics, Placenta, Viral evolution
Publisher URL http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0132563
Copyright Statement © 2015 Capellini et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Additional Information Copy of article first published in PLoS ONE, 2015, v.10, issue 7

Files

Published article (379 Kb)
PDF

Copyright Statement
© 2015 Capellini et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited











Downloadable Citations