Shoaling fish can size-assort by chemical cues alone
- 603 Downloads
Animals that form groups are typically assorted by phenotype. For example, fish shoals are notably composed of closely size-matched individuals, yet the sensory mechanisms that promote this behaviour have not been fully determined. Here, we show that two freshwater shoaling fish species, three-spined stickleback and banded killifish, have a greater preference for the chemical cues of conspecifics that are the same size as themselves than for those of larger or smaller conspecifics. We suggest that this ability to determine their own size relative to conspecifics may be based on chemical self-referencing. This provides a novel insight to the mechanisms underlying a widespread phenomenon in social behaviour, and provides further evidence of the crucial role played by chemical cues in structuring the interactions of fishes.
KeywordsShoaling Schooling Sociality Olfaction Sensory ecology
The authors would like to thank Professor Theo Bakker, the associate editor, Dr Jo Frommen, and two anonymous reviews for comments which greatly improved this manuscript.
All experiments reported here comply with the current laws of the country in which they were performed.
- Aeschlimann PB, Haberli MA, Reusch TBH, Boehm T, Milinski M (2003) Female sticklebacks Gasterosteus aculeatus use self-reference to optimize MHC allele number during mate selection. Behav Ecol Sociobiol 54:119–126Google Scholar
- Freon P (1984) Body length variability in fish schools and cohorts. 1. Observations and interpretation. Oceanol Acta 7:457–468Google Scholar
- Hara TJ (1992) Fish chemoreception. In: Fish and fisheries. Chapman & Hall, LondonGoogle Scholar
- Krause J, Ruxton GD (2002) Living in groups. Oxford University Press, Oxford, UKGoogle Scholar
- Sorensen PW, Stacey NE (1999) Evolution and specialization of fish hormonal pheromones. In: Advances in chemical signals in vertebrates edited by Johnston et al. Kluwer Academic, New YorkGoogle Scholar