Biology & Philosophy

, Volume 28, Issue 2, pp 299–330 | Cite as

The other eukaryotes in light of evolutionary protistology

  • Maureen A. O’Malley
  • Alastair G. B. Simpson
  • Andrew J. Roger


In order to introduce protists to philosophers, we outline the diversity, classification, and evolutionary importance of these eukaryotic microorganisms. We argue that an evolutionary understanding of protists is crucial for understanding eukaryotes in general. More specifically, evolutionary protistology shows how the emphasis on understanding evolutionary phenomena through a phylogeny-based comparative approach constrains and underpins any more abstract account of why certain organismal features evolved in the early history of eukaryotes. We focus on three crucial episodes of this history: the origins of multicellularity, the origin of sex, and the origin of the eukaryote cell. Despite ongoing uncertainty about where the root of the eukaryote tree lies, and residual questions about the precise endosymbioses that have produced a diversity of photosynthesizing eukaryotes, evolutionary protistology has illuminated with considerable clarity many aspects of protist evolution. Our main message in light of evolutionary protistology is that these ‘other eukaryotes’ are in fact the organisms through which the rest of the eukaryotes should be understood.


Protists Eukaryote tree of life Phylogeny-based comparison Origin of sex Origins of multicellularity Origin of eukaryotes 



We thank Mark Olson (UNAM) for detailed comments that greatly clarified our argument. MAO acknowledges funding from the Australian Research Council and University of Sydney in the form of a Future Fellowship; AGBS is supported by the Canadian Institute for Advanced Research program in Integrated Microbial Biodiversity, and a Discovery grant from the Natural Sciences and Engineering Research Council of Canada; AJR is supported by the Canada Research Chairs Program and a Discovery grant from the Natural Sciences and Engineering Research Council of Canada.


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Copyright information

© Springer Science+Business Media Dordrecht 2012

Authors and Affiliations

  • Maureen A. O’Malley
    • 1
  • Alastair G. B. Simpson
    • 2
  • Andrew J. Roger
    • 3
  1. 1.Department of PhilosophyUniversity of SydneySydneyAustralia
  2. 2.Department of Biology, Life Sciences CentreDalhousie UniversityHalifaxCanada
  3. 3.Department of Biochemistry and Molecular Biology, Tupper BuildingDalhousie UniversityHalifaxCanada

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