Horizontal persistence and the complexity hypothesis

Biology and Philosophy 35 (1):2 (2020)


This paper investigates the complexity hypothesis in microbial evolutionary genetics from a philosophical vantage. This hypothesis, in its current version, states that genes with high connectivity are likely to be resistant to being horizontally transferred. We defend four claims. There is an important distinction between two different ways in which a gene family can persist: vertically and horizontally. There is a trade-off between these two modes of persistence, such that a gene better at achieving one will be worse at achieving the other. At least some genes are likely to experience selection favoring increased transferability. One consequence of this can be encapsulated as the “simplicity hypothesis”: horizontally persisting genes will experience selection favoring reduced connectivity. In order to make sense of the simplicity hypothesis, we need to consider evolutionary populations that transcend species boundaries. Vertical and horizontal persistence are therefore not two competing ways of succeeding at the same game, but involve playing two different games altogether. The complexity hypothesis can be understood in terms of two related notions: entrenchment and Cuvierian functionalism. This framing reveals previously unrecognized and philosophically interesting connections between reasoning about deep conservation and horizontal transfer.

Download options


    Upload a copy of this work     Papers currently archived: 72,766

External links

Setup an account with your affiliations in order to access resources via your University's proxy server

Through your library


Added to PP

11 (#859,682)

6 months
1 (#386,499)

Historical graph of downloads
How can I increase my downloads?

Author Profiles

Aaron Novick
University of Washington
W. Doolittle
Dalhousie University

Citations of this work

Continuing After Species: An Afterword.Robert A. Wilson - 2022 - In John S. Wilkins, Igor Pavlinov & Frank Zachos (eds.), Species Problems and Beyond: Contemporary Issues in Philosophy and Practice. New York: Routledge. pp. 343-353.

Add more citations

Similar books and articles

The Trade-Off Between Speed and Complexity.Mark Andrew Changizi - 2008 - Behavioral and Brain Sciences 31 (2):203-203.
Evolution of Human Jealousy a Just-so Story or a Just-so Criticism?Neven Sesardic - 2003 - Philosophy of the Social Sciences 33 (4):427-443.
Making the Most of Clade Selection.W. Ford Doolittle - 2017 - Philosophy of Science 84 (2):275-295.
Imagining, Recognizing and Discriminating: Reconsidering the Ability Hypothesis.Bence Nanay - 2009 - Philosophy and Phenomenological Research 79 (3):699-717.