Biological Theory

, Volume 11, Issue 3, pp 138–149 | Cite as

Rethinking Cohesion and Species Individuality

  • Celso NetoEmail author
Original Article


According to the species-as-individuals thesis (hereafter S-A-I), species are cohesive entities. Barker and Wilson recently pointed out that the type of cohesion exhibited by species is fundamentally different from that of organisms (paradigmatic individuals), suggesting that species are homeostatic property cluster kinds. In this article, I propose a shift in how to approach cohesion in the context of S-A-I: instead of analyzing the different types of cohesion and questioning whether species have them, I focus on the role played by cohesion in the identity of individuals. This shift allows us to recognize why cohesion matters to S-A-I, as well as to reconceive the analogy between species and organisms (paradigmatic individuals), and also allows us to highlight the context sensitivity of both “cohesion” and “individuals.” From this perspective, I identify two problems in Barker and Wilson’s argumentation. Firstly, the authors fail to recognize that species are individuals even if they do not have the same type of cohesion that organisms have. Secondly, their argument relies on a misinterpretation of S-A-I. I conclude that species cohesion is still best framed as a feature of species individuality rather than a feature of species as homeostatic property cluster kinds. The arguments presented here contribute to the re-articulation and reevaluation of S-A-I in the face of contemporary discussions.


Classes Cohesion Homeostatic property cluster kinds Identity Species 



For providing helpful comments on early versions I thank Thomas Reydon, Matthew Haber, and Matthew Barker. I also thank two anonymous reviewers for their valuable comments. For providing financial support I thank the Brazilian National Council for Scientific and Technological Development (Conselho Nacional de Desenvolvimento Científico e Tecnológico—CNPq), grant no. 200188/2014-3.


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Copyright information

© Konrad Lorenz Institute for Evolution and Cognition Research 2016

Authors and Affiliations

  1. 1.Philosophy InstituteLeibniz UniversityHannoverGermany
  2. 2.Center for Philosophy and Ethics of ScienceLeibniz UniversityHannoverGermany

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