Visitors to Bristol Zoo sported beards in honour of one of the most important scientists of all time.

The event marked the 200th birthday of Charles Darwin, whose book On The Origin of Species outlined the theory of evolution and transformed our understanding of the natural world.

In honour of the naturalist, who in later years sported a long white beard caricatured by cartoonists, anyone who wore a real or fake beard yesterday was allowed into the zoo for free.

Among those who got into the spirit of the birthday celebrations were pupils from Saltford Primary School, who visited for an education session on how animals adapt to survive in different climates.

Simon Garrett, head of learning at the zoo, said: "Darwin is now a household name and, over the last 150 years, his ideas have revolutionised our understanding of nature and our place within it. Bristol Zoo's 'beard day' is a fun way of commemorating Darwin's life and work while allowing visitors to find out more about his theories."

Visitors to the Zoo can also take part in the zoo's Darwin-themed trail, 'Be a Darwin Detective'.

Other Darwin-themed activities will take place throughout the year, which also marks the 150th anniversary of the first publication of On The Origin of Species. For more details visit www.bristolzoo.org.uk