1. Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN 37996, USA
2. Department of Mathematics, University of Tennessee, Knoxville, TN 37996, USA
3. Center for the Dynamics of Social Complexity, University of Tennessee, Knoxville, TN 37996, USA
4. Grupo Interdisciplinar de Sistemas Complejos, Departamento de Matemáticas Universidad Carlos III de Madrid, Leganés, Madrid 28911, Spain
5. Instituto de Biocomputación y Física de Sistemas Complejos, Universidad de Zaragoza, Zaragoza 50018, Spain