Salikoko S. Mufwene is Professor of Linguistics and member of the Committee on Evolutionary Biology and the Commitee on the Conceptual and Historical Studies of Science, at the University of Chicago. He is the author of The Ecology of Language Evolution (Cambridge, 2001), Créoles, écologie sociale, évolution linguistique (2005), and Language Evolution: Contact, Competition and Change (2008). He has edited several books, including Iberian Imperialism and Language Evolution in Latin America (2014). He is the founding editor of the Cambridge Approaches to Language Contact series. His research includes the emergence of creoles, the phylogenetic emergence of language, and globalization and language vitality. Christophe Coupé is a researcher in cognitive science at the Centre National de la Recherche Scientifique (CNRS), Paris and Université Lumière Lyon II, France. With a background in computer science, cognitive science and psychology, he has been involved in several multidisciplinary programs focusing on language complexity, language origins and language change. His contributions have mostly consisted of the design and analyses of databases, and of statistical or computational models of linguistic evolution and diversity. In 2003, he received the Prize of the Young Researcher of the city of Lyon for his Ph.D. dissertation on the origins of language. In addition to other papers on phonological complexity, information rate and functional load, he has co-edited the collective volume Approaches to Phonological Complexity (2009). François Pellegrino is a senior researcher in linguistics and cognitive science at the Centre National de la Recherche Scientifique (CNRS), Paris and Université Lumière Lyon II, France. He has coordinated several projects on language complexity and has been the coordinator of the 'Laboratory of Excellence' ASLAN (Advanced Studies on Language Complexity) since 2011. For more than ten years, his research has focused on the structure and dynamics of phonological systems in the light of the science of complexity and of Shannon's information theory. He has co-edited the collective volume Approaches to Phonological Complexity (2009) and, over the last fifteen years, he has authored or co-authored about eighty journal articles, book chapters or conference papers.