I studied Linguistics at the University of Cambridge and taught Russian and Linguistics there for six years before moving to the Linguistics Department of the University of Southern California, where I taught for 20 years. In 1998 I moved to Germany to take up the directorship of the Department of Linguistics at the Max Planck Institute for Evolutionary Anthropology in Leipzig, a position from which I retired in 2015. From 2002 to 2021 I was Distinguished Professor of Linguistics at the University of California, Santa Barbara.

I believe that an understanding of Language requires an understanding of as many languages of different types as possible, and this has led me to carry out fieldwork in places as far apart as Papua New Guinea and the North Caucasus – I have been known to say: “If it’s a language, I’ll work on it.” Topics I have investigated from this cross-linguistic, typological perspective include tense and aspect, relative clauses, transitivity and voice, and numeral systems. My interests in new directions in historical linguistics have led me to seek out collaborations with population geneticists, archeologists, and anthropologists to combine the strengths of these disciplines in solving problems relating to prehistoric human migrations.