Dynamics of sibling aggression of a cichlid fish in Lake Tanganyika
- 28 Downloads
Siblings often compete for limited resources, particularly food provided by their parents. Such competition is usually nonviolent, but direct aggression has evolved in some species. However, there is little knowledge about sibling aggression in species without parental provisioning. Here, we investigated sibling aggression in the cichlid Neolamprologus furcifer in Lake Tanganyika, Zambia. In this species, females guard their broods in the nest but do not provide any food. Early-stage fry did not show any sibling aggression while foraging on plankton, but began to show nonlethal aggression once they started to forage on small benthic shrimp at 2 weeks of age. The frequency of sibling aggression decreased at week 7, when the density of fry decreased remarkably. Sibling aggression also decreased following a short-term increase in food through supplemental feeding. The aggression was higher in the morning than in the afternoon despite higher abundance of shrimp at that time, and decreased when the number of shrimp in the nest was experimentally reduced. These results indicate that food availability affects sibling aggression of animals that do not exhibit parental provisioning.
KeywordsParental care Sibling competition Food availability Neolamprologus furcifer Aggressive behavior Food amount hypothesis
The authors thank the members of the Maneno Tanganyika Research team and the Animal Sociology Laboratory of the Osaka City University for their helpful comments. The authors are also grateful to two anonymous reviewers who made helpful suggestions for improving this paper. This study was financially supported by KAKENHI (Nos. 26540070 and 26118511) grants awarded to M.K. and (No. H17J11490) also to S.S.
- Brichard, P., 1978. Fishes of Lake Tanganyika. T.F.H. Publication, Neptune City.Google Scholar
- Brown, J. L., 1964. The evolution of diversity in avian territorial systems. The Wilson Bulletin 76: 160–169.Google Scholar
- Brown, L. H. & D. Amadon, 1968. Eagles, Hawks and Falcons of the World. The Wellfleet Press, New York.Google Scholar
- Hori, M., 1983. Feeding ecology of thirteen species of Lamprologus (Teleostei; Cichlidae) coexisting at a rocky shore of Lake Tanganyika. Physiology and Ecology Japan 20: 129–149.Google Scholar
- Keenleyside, M. H. A., 1991. Parental care. In Keenleyside, M. H. A. (ed.), Cichlid Fishes: Behaviour, Ecology and Evolution. Chapman and Hall, London: 191–208.Google Scholar
- Matray, P. F., 1974. Broad-winged Hawk nesting and ecology. The Auk 91: 307–324.Google Scholar
- Mock, D. W. & G. A. Parker, 1997. The Evolution of Sibling Rivalry. Oxford University Press, Oxford.Google Scholar
- Nagoshi, M. & M. M. Gashagaza, 1988. Growth of the larvae of a Tanganyikan cichlid, Lamprologus attenuatus, under parental care. Japanese Journal of Ichthyology 35: 392–395.Google Scholar
- R Core Team, 2014. R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. https://www.R-project.org/.
- Roulin, A. & A. N. Dreiss, 2012. Sibling competition and cooperation over parental care. In Nick, J. R., P. T. Smiseth & M. Kölliker (eds), The Evolution of Parental Care, 2012. Oxford University Press, Oxford: 133–149.Google Scholar
- Stearns, S. C., 1992. The Evolution of Life Histories. Oxford University Press, Oxford.Google Scholar
- Yanagisawa, Y., 1987. Social organization of a polygynous cichlid Lamprologus furcifer in Lake Tanganyika. Japanese Journal of Ichthyology 34: 82–90.Google Scholar