1. Institut de Biologia Evolutiva (CSIC-UPF), 08003 Barcelona, Spain
2. ICREA-Complex Systems Lab, Universitat Pompeu Fabra, 08003 Barcelona, Spain
3. Evolution of Technology Lab, Institut de Biologia Evolutiva (CSIC-UPF), 08003 Barcelona, Spain
4. Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, New Mexico 87501, United States