Microbial warfare and the evolution of symbiosis

Patel, Matishalin; West, Stuart

Abstract

Cooperative symbionts enable their hosts to exploit a diversity of environments. A low genetic diversity (high relatedness) between the symbionts within a host is thought to favour cooperation by reducing conflict within the host. However, hosts will not be favoured to transmit their symbionts (or commensals) in costly ways that increase relatedness, unless this also provides an immediate fitness benefit to the host. We suggest that conditionally expressed costly competitive traits, such as antimicrobial warfare with bacteriocins, could provide a relatively universal reason for why hosts would gain an immediate benefit from increasing the relatedness between symbionts. We theoretically test this hypothesis with a simple illustrative model that examines whether hosts should manipulate relatedness, and an individual-based simulation, where host control evolves in a structured population. We find that hosts can be favoured to manipulate relatedness, to reduce conflict between commensals via this immediate reduction in warfare. Furthermore, this manipulation evolves to extremes of high or low vertical transmission and only in a narrow range is partly vertical transmission stable.

Citation

Patel, M., & West, S. (2022). Microbial warfare and the evolution of symbiosis. Biology Letters, 18(12), Article 20220447. https://doi.org/10.1098/rsbl.2022.0447

• Journal Article Type: Article
• Acceptance Date: Nov 23, 2022
• Online Publication Date: Dec 21, 2022
• Publication Date: Dec 1, 2022
• Deposit Date: May 15, 2023
• Publicly Available Date: May 15, 2023
• Journal: Biology Letters
• Print ISSN: 1744-9561
• Electronic ISSN: 1744-957X
• Publisher: The Royal Society
• Peer Reviewed: Peer Reviewed
• Volume: 18
• Issue: 12
• Article Number: 20220447
• DOI: https://doi.org/10.1098/rsbl.2022.0447
• Keywords: Microbial; Evolution; Symbiosis; Conflict; Mutualisms
• Public URL: https://hull-repository.worktribe.com/output/4290932