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The ecology and diversity of microbial eukaryotes in geothermal springs

The ISME Journalvolume 12pages19181928 (2018) | Download Citation


Decades of research into the Bacteria and Archaea living in geothermal spring ecosystems have yielded great insight into the diversity of life and organismal adaptations to extreme environmental conditions. Surprisingly, while microbial eukaryotes (protists) are also ubiquitous in many environments, their diversity across geothermal springs has mostly been ignored. We used high-throughput sequencing to illuminate the diversity and structure of microbial eukaryotic communities found in 160 geothermal springs with broad ranges in temperature and pH across the Taupō Volcanic Zone in New Zealand. Protistan communities were moderately predictable in composition and varied most strongly across gradients in pH and temperature. Moreover, this variation mirrored patterns observed for bacterial and archaeal communities across the same spring samples, highlighting that there are similar ecological constraints across the tree of life. While extreme pH values were associated with declining protist diversity, high temperature springs harbored substantial amounts of protist diversity. Although protists are often overlooked in geothermal springs and other extreme environments, our results indicate that such environments can host distinct and diverse protistan communities.

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We thank Karen Houghton, Carlo Carere, Hanna-Annette Peach and David Evans for assistance with sample collection and Jessica Henley, Roanna Richards-Babbage, and Georgia Wakerley for assistance with laboratory work. We thank Lauren Shoemaker, Amber Churchill, and Manuel Delgado-Baquerizo for valuable comments. This project was funded by an NSF Graduate Research Fellowship, NSF EAPSI Fellowship, and Lewis and Clark Fund Scholarship to AMO, and MBIE grant C05X1205 to JFP, SCC, and MBS.

Author contributions

AMO, NF, MBS, and SCC designed and performed the research analyzed the data. AMO and NF wrote the manuscript with aid from AW, MBS, SCC, and JFP.

Author information


  1. Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, 80309, USA

    • Angela M. Oliverio
    •  & Noah Fierer
  2. Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, 80309, USA

    • Angela M. Oliverio
    •  & Noah Fierer
  3. Extremophile Research Group, GNS Science, Private Bag 2000, Taupō, 3352, New Zealand

    • Jean F. Power
    •  & Matthew B. Stott
  4. Thermophile Research Unit, School of Science, University of Waikato, Private Bag 3105, Hamilton, 3240, New Zealand

    • Jean F. Power
    •  & S. Craig Cary
  5. Department of Microbiology and Immunology, Montana State University, Bozeman, MT, 59717, USA

    • Alex Washburne


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The authors declare that they have no conflict of interest.

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Correspondence to Noah Fierer.

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