RT Journal Article SR Electronic T1 Soil Protists in Three Neotropical Rainforests are Hyperdiverse and Dominated by Parasites JF bioRxiv FD Cold Spring Harbor Laboratory SP 050997 DO 10.1101/050997 A1 Frédéric Mahé A1 Colomban de Vargas A1 David Bass A1 Lucas Czech A1 Alexandros Stamatakis A1 Enrique Lara A1 David Singer A1 Jordan Mayor A1 John Bunge A1 Sarah Sernaker A1 Tobias Siemensmeyer A1 Isabelle Trautmann A1 Sarah Romac A1 Cédric Berney A1 Alexey Kozlov A1 Edward A.D. Mitchell A1 Christophe V. W. Seppey A1 Elianne Egge A1 Guillaume Lentendu A1 Rainer Wirth A1 Gabriel Trueba A1 Micah Dunthorn YR 2016 UL http://biorxiv.org/content/early/2016/11/03/050997.abstract AB Animal and plant richness in tropical rainforests has long intrigued naturalist. More recent work has revealed that parasites contribute to high tropical tree diversity (Bagchi et al., 2014; Terborgh, 2012) and that arthropods are the most diverse eukaryotes in these forests (Erwin, 1982; Basset et al., 2012). It is unknown if similar patterns are reflected at the microbial scale with unicellular eukaryotes or protists. Here we show, using environmental metabarcoding and a novel phylogeny-aware cleaning step, that protists inhabiting Neotropical rainforest soils are hyperdiverse and dominated by the parasitic Apicomplexa, which infect arthropods and other animals. These host-specific protist parasites potentially contribute to the high animal diversity in the forests by reducing population growth in a density-dependent manner. By contrast, we found too few Oomycota to broadly drive high tropical tree diversity in a host-specific manner under the Janzen-Connell model (Janzen, 1970; Connell, 1970). Extremely high OTU diversity and high heterogeneity between samples within the same forests suggest that protists, not arthropods, are the most diverse eukaryotes in tropical rainforests. Our data show that microbes play a large role in tropical terrestrial ecosystems long viewed as being dominated by macro-organisms.Contact: dunthorn@rhrk.uni-kl.de