首页 | 本学科首页   官方微博 | 高级检索  
   检索      


Optimal growth strategies under divergent predation pressure
Authors:S Aikio  G Herczeg  A Kuparinen  J Merilä
Institution:1. Plant Ecology and Population Biology Research Group, Department of Biology, P. O. Box 3000, FIN‐90014 University of Oulu, Oulu, Finland;2. Ecological Genetics Research Unit, Department of Biosciences, P. O. Box 65, FIN‐00014 University of Helsinki, Helsinki, Finland
Abstract:The conditions leading to gigantism in nine‐spined sticklebacks Pungitius pungitius were analysed by modelling fish growth with the von Bertalanffy model searching for the optimal strategy when the model's growth constant and asymptotic fish size parameters are negatively related to each other. Predator‐related mortality was modelled through the increased risk of death during active foraging. The model was parameterized with empirical growth data of fish from four different populations and analysed for optimal growth strategy at different mortality levels. The growth constant and asymptotic fish size were negatively related in most populations. Optimal fish size, fitness and life span decreased with predator‐induced mortality. At low mortality, the fitness of pond populations was higher than that of sea populations. The differences disappeared at intermediate mortalities, and sea populations had slightly higher fitness at extremely high mortalities. In the scenario where all populations mature at the same age, the pond populations perform better at low mortalities and the sea populations at high mortalities. It is concluded that a trade‐off between growth constant and asymptotic fish size, together with different mortality rates, can explain a significant proportion of body size differentiation between populations. In the present case, it is a sufficient explanation of gigantism in pond P. pungitius.
Keywords:body size  gigantism  model  population  Pungitius
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号