David went on to do natural sciences at Cambridge. Rejecting an academic career, as he did not want to be stuck in labs and lecture halls, he joined the Royal Navy hoping to see the world. However, he left after 3 years and went on to publishing and editing textbooks for children.

In 1952, David joined the BBC, at first co-presenting a show called The Pattern of Animals with Sir Julian Huxley and slowly progressed to both presenting and writing his own shows.

Eventually, he was promoted to Controller of BBC2, overseeing the entrance of colour television to Britain and a few years later, became the Director of Programming for both BBC1 and BBC2.

David returned to the screen in 1973, making natural history and environmental documentaries. Till today, he still amazes his audiences and works to bring nature closer to everyone. Being a prominent figurehead, his views on the environment are well documented and valued.