1. Centre for Integrative Ecology School of Biological Sciences University of Canterbury Private Bag 4800 Christchurch 8140 New Zealand
2. Biomathematics Research Centre School of Mathematics and Statistics University of Canterbury Private Bag 4800 Christchurch 8140 New Zealand
3. Department of Physics, Chemistry, and Biology (IFM) Linköping University 581 83 Linköping Sweden