In a nutshell Worldwide travel happens all the time today but in the 18th century, of course it was rare. Pennant is still remembered for his great work, British Zoology, a watershed in the history of biology.
Track record Pennant travelled a great deal throughout Britain and Europe, always on horseback and usually with his servant-artist, Moses Griffiths.
Scientific illustrations were his big thing. He was an early pioneer in looking at the countryside for pleasure, an attitude which eventually led to the creation of organisations like The National Trust and National Parks, which nowadays we take for granted. It's not too extreme to suggest that today's Green Movement should adopt Thomas as its patron saint: a picture of him would be an appropriate logo.
He had a privileged upbringing, but was generous. In the hard winter of 1783 he arranged for 'sustenance to 576 poor people.'
The Science Pennant was a zoologist. Today he would be described as a taxonomist, someone who specialises in the classification of biological specimens along the lines of the Swedish biologist Linneaus. Pennant was famous for his huge number of illustrations.
His book British Zoology was first published in 1761 and was a huge success, being translated into several European languages. There were 132 engraved plates just in the first volume, each one illustrating a particular species along with a description of its morphology (the study of the form of animals and plants) and natural history.
As Dr Samuel Johnson wrote, 'Pennant was the best traveller I ever read; he observes more things than any one else does.'