SREL Reprint #3511

Geographical and host species barriers differentially affect generalist and specialist parasite community structure in a tropical sky-island archipelago

Pooja Gupta1,2, C. K. Vishnudas3, Uma Ramakrishnan4, V. V. Robin3, and Guha Dharmarajan1

1Savannah River Ecology Laboratory, University of Georgia, Aiken, SC, USA
2Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA
3Indian Institute of Science Education and Research Tirupati, Mangalam, Tirupati 517507, India
4National Centre for Biological Sciences, TIFR, Bangalore 560065, India

Abstract: Understanding why some parasites emerge in novel host communities while others do not has broad implications for human and wildlife health. In the case of haemosporidian blood parasites, epidemic wild bird mortalities on oceanic islands have been linked to Plasmodium spp., but not genera like Haemoproteus. Indeed, Haemoproteus is absent from many oceanic islands. By contrast, birds on continental islands share long coevolutionary histories with both Plasmodium and Haemoproteus, and are thus ideal model systems to elucidate eco-evolutionary endpoints associated with these parasites in oceanic islands. Here, we examine eco-evolutionary dynamics of avian haemosporidian in the Shola sky-island archipelago of the Western Ghats, India. Our analyses reveal that compared to Plasmodium, Haemoproteus lineages were highly host-specific and diversified via co-speciation with their hosts.We show that community structure of host-generalist Plasmodium was primarily driven by geographical factors (e.g. biogeographic barriers), while that of host-specialist Haemoproteus was driven by host species barriers (e.g. phylogenetic distance). Consequently, a few host species can harbour a high diversity of Plasmodium lineages which, in turn, are capable of infecting multiple host species. These two mechanisms can act in concert to increase the risk of introduction, establishment, and emergence of novel Plasmodium lineages in island systems.

Keywords: avian haemosporidians, Plasmodium, Haemoproteus, disease emergence, community structure, India

SREL Reprint #3511

Gupta, P., C. K. Vishnudas, U. Ramakrishnan, V. V. Robin, and G. Dharmarajan. 2019. Geographical and host species barriers differentially affect generalist and specialist parasite community structure in a tropical sky-island archipelago. Proceedings of the Royal Society B 286(1904): 20190439.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).