Sex-specific differences in shoaling affect parasite transmission in guppies

• Published in: PloS one Vol. 5; no. 10; p. e13285
• Main Authors: Richards, E Loys, van Oosterhout, Cock, Cable, Joanne
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 11.10.2010; Public Library of Science (PLoS)
• Subjects: Analysis; Animals; Behavior, Animal; Cost benefit analysis; Cyprinodontidae; Disease transmission; Ecology/Behavioral Ecology; Ecology/Community Ecology and Biodiversity; Ecology/Marine and Freshwater Ecology; Experimental infection; Female; Females; Fish; Fish parasites; Fundulus diaphanus; Gambusia affinis; Gasterosteus; Genomes; Group dynamics; Gyrodactylus; Gyrodactylus turnbulli; Health risks; Infections; Infectious Diseases/Helminth Infections; Influence; Male; Males; Parasites; Poecilia - parasitology; Poecilia reticulata; Poeciliidae; Sex; Sex Factors; Sexual selection; Shoals; Teleostei
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0013285

Individuals have to trade-off the costs and benefits of group membership during shoaling behaviour. Shoaling can increase the risk of parasite transmission, but this cost has rarely been quantified experimentally. Guppies (Poecilia reticulata) are a model system for behavioural studies, and they are commonly infected by gyrodactylid parasites, notorious fish pathogens that are directly transmitted between guppy hosts. Parasite transmission in single sex shoals of male and female guppies were observed using an experimental infection of Gyrodactylus turnbulli. Parasite transmission was affected by sex-specific differences in host behaviour, and significantly more parasites were transmitted when fish had more frequent and more prolonged contact with each other. Females shoaled significantly more than males and had a four times higher risk to contract an infection. Intersexual differences in host behaviours such as shoaling are driven by differences in natural and sexual selection experienced by both sexes. Here we show that the potential benefits of an increased shoaling tendency are traded off against increased risks of contracting an infectious parasite in a group-living species.