Sir William Colin Mackenzie (9 March 1877 – 29 June 1938), usually known as Colin Mackenzie, was an Australian anatomist, benefactor, museum administrator and director. He was best known for creating Healesville Sanctuary.
Mackenzie was the youngest son of John Mackenzie, a draper, and Anne, née McKay, both of Scottish origin. He was born at Kilmore, Victoria and was educated at the local state school, continuing his education at Scotch College, Melbourne after obtaining a scholarship. He qualified for matriculation with honours in Greek at the end of 1893, and beginning his course at the University of Melbourne soon afterwards, graduated MB, with first class honours in surgery, obstetric medicine and diseases of women and children in 1899. He later took out a BS degree in 1902.
Mackenzie had a year's hospital practice at the Royal Melbourne Hospital, for two years was senior resident medical officer at the Royal Children's Hospital, and was in general practice for some time at North Melbourne. In 1904 he paid his first visit to Europe and obtained by examination his fellowship of the Royal College of Surgeons of Edinburgh. At the Children's hospital, Melbourne, he had been much interested in the problem of the after treatment of infantile paralysis, and while in Europe worked with Professor Vulpius at Heidelberg, and studied the work being done by Sir Robert Jones at Liverpool. Coming back to Australia, he found there was then a severe epidemic of infantile paralysis, and was able to use his newly acquired knowledge of the principles of muscle rest and recovery. He was not, however, content to merely follow other men. He felt that the main problem was how to bring the muscles into normal use again, and however commonplace his methods may seem today, at the time, they appeared to be revolutionary. He was the first to Speak of "muscle re-education" and to realise the importance of the action of gravity in attempts to regain muscle function.