He had seven older sisters and two younger brothers and his early life was overshadowed by a terrible relationship with his father, a reactionary conservative whose character Watson himself detailed in later years.
[1] As a teenager, Watson suffered a serious injury to his knee in a cricket match, and never recovered full movement in the joint again.
While training for the legal profession in Liverpool, Watson became interested in phrenology and decided to study medicine and natural history at Edinburgh University (from 1828 to 1832).
He was elected a Senior President of the Royal Medical Society as an undergraduate, but left without taking a degree because of a breakdown in his health.
He travelled to the Azores in 1842, spending three months collecting botanical specimens from four of the larger islands, while serving at his own expense as ship's botanist for the Styx under the command of Captain Vidal.
In subsequent years, Watson was heavily influenced by the ideas of the evolutionary phrenologist Robert Chambers, and collected evidence for – and defended – the concept of species transmutation.
In 1856, Watson actually declined a personal invitation to discuss evolutionary theory with Darwin and Joseph Hooker, because he was too busy and did not wish to travel.