He served in the Royal Navy from 1947 to 1949 before joining the BBC but was initially discouraged from appearing on screen because his bosses thought his teeth were too big.
A committed Londoner, he is equally at home in the wildest and most remote parts of the world.
His combination of charm and an ability to put across his wide knowledge in an attractive and compelling way has been much-imitated but rarely replicated.
Long before environmental issues were making daily headlines, he was a fervent eco campaigner both on and off screen.
His 2000 series State of the Planet and Are We Changing Planet Earth?
in 2006 dealt heavily with environmental issues such as global warming.
As a younger man, he famously often travelled in economy class on flights, only accepting upgrades if they were extended to his crew as well.
When he turned 75, the BBC reportedly told him he should fly in business class.
He still frequently diverts praise about his work to the people behind the camera.
Something remarkable happened 200 million years ago.
For the first time, backboned creatures left the ground and took to the skies.
They were reptiles called pterosaurs, and over millions of years, they evolved into a huge variety of species, some the size of airplanes.