New Review of “Kin Recognition in Protists and Other Microbes”

By Guillermo Paz-y-Miño-C

Joachim “Jo” G. Frommen, a behavioral ecologist at the University of Bern, has written a review of our book “Kin Recognition in Protists and Other Microbes: Genetics, Evolution, Behavior and Health.” The article came out (as early view) in the Journal of Eukaryotic Microbiology (JEUK-MIC). Before sharing details of Jo’s take on our work, here is an excerpt that captures his overall opinion:

This a highly timely and interesting book. People not being too familiar with microbiology will find it a fascinating and inspiring introduction into kin recognition in non-animal systems, which thereby challenges our thinking of underlying cognitive processes such as learning. Students of evolutionary biology will find it highly useful to read, for example, about the advent of multicellularity and sociality, leading to major transitions in evolution. Researchers in microbiology will appreciate a comprehensive summary of the field, with some additional dives into methodological details. Teachers will take advantage of the more than 120 detailed figures showing experimental setups, results and schematic diagrams, as well as of the great appendix linking to recent media resources that can be downloaded and included in lectures… This is a great book, which I can highly recommend.”

Well, first, thanks to Jo for a sharp and generous assessment. Avelina Espinosa (my coauthor) and I were quite pleased to see that Jo grasped the book precisely in the way we wrote it, plus the intention with which we put it together. We spent much time conceptualizing the chapters, their order and content, the illustrations and terminology boxes, the recapitulations of previous sections prior to “diving” deeper into more complex themes, and the didactic summaries at the end of each major subject.

Jo further summarizes the book as follows:

“…Chapter one (Kin recognition: Synopsis and the advent of protists models) sets the stage for the following chapters by explaining the most important terms and concepts of the kin recognition literature. It further highlights the importance of kin recognition in animals and introduces protists as promising model organisms. Chapter two (The genetics of kin recognition: from many cells to single cells) explains the genetic mechanisms of kin recognition (e.g. green beard effects) using red fire ants (Solenopsis invicta) and social ameba (Dictyostelium discoideum) as examples. Chapter three (Can protists learn phenotypic cues to discriminate kin?) introduces learning as possible nongenetic kin recognition mechanisms. While this chapter is intentionally rather speculative, it is highly inspiring at the same time when thinking about definitions of terms like learning or memory. Chapter four (Entamoeba clone-recognition experiments: morphometrics, aggregative behavior, and cell-signaling characterization) introduces one of the authors’ own study systems, and how it might help us understanding clone recognition. Although the book focuses mainly on kin recognition in protists, the authors devote almost 100 pages of chapter five (The prokaryote´s tale) to show the impact of relatedness on the evolution, ecology and pathogenicity of prokaryotes. By doing so, they largely increase the breadth and information content of the book and open it to a wider audience…

Indeed, Jo got it just right. We purposely dedicated a comprehensive chapter to kin discrimination/recognition in bacteria (most case studies) and Archaea (a few case studies). In fact, there is so much excellent research in prokaryotes that a book dedicated entirely to them should be compiled (not by us, but by somebody else).

Jo continues:

[click to enlarge]

…Chapter six (Protists´ clonality, kinship and pathogenicity) illuminates the gregarious and social behaviors of pathogenic protists like Plasmodium or Trypanosoma. In chapter seven (Micro-biogeography: kinship and social/spatial structure) the authors focus on the local and global distributions of various protist species, with a special focus on Becking’s Everything is Everywhere hypothesis. Chapter eight (Multicellular aggregations: from single cells to many cells) highlights the importance of understanding the multifarious levels of protists’ social organization and cooperation, when aiming to understand the evolution of multicellularity more generally, which is considered as one of the Major Transitions in Evolution. The short ninth chapter (Conclusions and future directions) eventually provides a brief summary of the book and suggests promising future research avenues for the study of kin recognition in protists…

Yes, we do suggest in the book some directions in which the field of kin discrimination/recognition could venture in the immediate and longer-term future, particularly now that unicellular organisms have been incorporated into research programs worldwide. We state, for example, that “…despite the academic progress made during the past two decades, the field of kin recognition in protists and other microbes is just getting started. For the immediate future, we predict a significant increase in studies on the genetics, evolution, behavior and health aspects of the cell-to-cell molecular mechanisms of communication, cooperation, facultative or permanent multicellular aggregations, as well as mathematical modeling on high-complexity organismal systems, and their interactions, for which microbes will generate the data central to the simulations.”

Jo makes a fair observation:

…As a grain of salt, I would have loved to see some more terminological strictness at some occasions. The field of kin recognition is full of semantic debates, often leading to confusion whenever researchers from different backgrounds come together. The same is also true for the concept of learning. Defining clear terms before opening the discussion would have been helpful to the reader, even if not everybody may agree on the definition itself. The authors acknowledge this mess of concepts and try to avoid the debate by using very broad definitions, which I agree are inclusive, but may be too broad to be useful at the same time. However, these are very minor shortcomings that reflect current debates in the field and do not diminish the scientific and scholarly value of this great book, which I can highly recommend.

Yes, as we noted in the book “…the field of kin recognition, has no consensus on definitions or proposed mechanisms, likely due to the vast diversity and complexity of life histories across organisms, and also because researchers use terminology depending on circumstances or preference…” We deliberately avoided the discussion of terms and the way they have been used by specialists in the field, a debate that goes back decades, and a topic that might require a separate review for comprehensive coverage. Terminology guides us and is central to scientific inquiry; but it can, occasionally, drag us back and prevent us from making progress, or even accepting the obvious, like “learning abilities” in microbes, which continue to be skeptically honored by scholars due to the customary deference for “high-cognition learning in humans” versus the “learning-like mechanisms” in other organisms. Research with microbes suggests that learning is ubiquitous in nature and that “unicells” sense stimuli coming from the environment, selectively react to chemosignals excreted by themselves or others, store information about such signals and retrieve it when needed (although, in our book we linked “potential learning” primarily to protists’ recognition/discrimination of close genetic relatives, kin).

In sum, Avelina and I thank Jo Frommen for his attentive and positive review of “Kin Recognition in Protists and Other Microbes: Genetics, Evolution, Behavior and Health.” ‒ EvoLiteracy © 2019

Follow us on Twitter and Facebook @gpazymino and GPC-Facebook 

Related Readings

Other Reviews of Kin Recognition in Protists and Other Microbes

Book Website

Link to Book at publisher Cambridge Scholars