is a veterinary surgeon, now retired, who worked from 1966 to 2004 at the Poultry Research Centre and the Roslin Institute at Edinburgh. His research was on poultry behaviour and welfare, focussing especially on specific appetites, laying behaviour, egg shell quality, feather pecking and housing systems. He headed the Ethology Department from 1988 to 1997 and was Institute Named Veterinary Surgeon and Chair of the Ethics Committee from 1993 to 2004. He was also a Tutor in the Open University on Biology, Brain and Behaviour and Lecturer on Edinburgh University's MSc course in Applied Animal Behaviour and Welfare. He was Editor of British Poultry Science from 1985 to 2010 and remains on the Editorial Board.
