Maggie Tallerman is Professor of Linguistics at Newcastle University. She has spent her professional life in North East England, having previously taught for 21 years at Durham University. Her research interests centre on the origins and evolution of syntax and morphology; modern Brythonic Celtic syntax and morphology; and language typology. Her publications include Understanding Syntax (Hodder/OUPUSA, 1998; 3rd edn. 2011); with Robert D. Borsley and David Willis, The Syntax of Welsh (CUP, 2007); and, as editor, Language Origins: Perspectives on Evolution (OUP, 2005). She is also the editor of the series Palgrave Modern Linguistics. Kathleen R. Gibson is Professor Emerita, Neurobiology and Anatomy, University of Texas Houston. Her co-edited books include, with Sue T. Parker, Language' and Intelligence in Monkeys and Apes (CUP 1990); with Tim Ingold, Tools, Language, and Cognition in Human Evolution (CUP 1993); with Paul Mellars, Modelling the Early Human Mind (McDonald Archaeological Institute 1996); and, with Dean Falk, Evolutionary Anatomy of the Human Neocortex (CUP 2001). She is the co-editor with James R. Hurford of the series, Oxford Studies in the Evolution of Language.