Major moments that changed our understanding of the planet we live on
Since 1975, San Diego Zoo has been deep-freezing cell samples from rare species
Whales were being hunted to extinction until a biologist realised they could sing.
A book that helped launch the green movement highlighted the damage caused by pesticides
A flightless bird, the dodo was extinct just decades after being discovered by Europeans
How scientists discovered that a deadly fungus was killing off amphibians.
A reactor caught fire at the Windscale nuclear plant in the north of England in 1957
Meticulously recorded levels of CO2 in the atmosphere show how our climate is changing
In the late 1950s thousands of people in Japan were poisoned by industrial waste
In the mid 1960s a Dutch engineer came up with a scheme to share bikes and cut pollution.
Forty five years ago it was the biggest oil spill the world had ever seen.
Did a nerve agent kill 6,000 sheep close to a US military testing site in 1968?
In June 1969 the heavily polluted Cuyahoga River, in Ohio in the USA, caught fire
Dr Norman Borlaug’s pioneering work on disease-resistant grains saved millions.
In 1970, 20 million Americans came out to demonstrate for a sustainable environment.
On June 27th 1975 Greenpeace activists launched their first direct action against whalers
An international conference in 1985 changed the history of climate change
James Hansen got US politicians to listen to his warnings about climate change in 1988.
Remembering the Brazilian environmental campaigner Chico Mendes, shot dead in 1988
In March 1989, the Exxon Valdez went aground, spilling 11 million gallons of oil
In 1997, a patch of plastic waste was discovered in the middle of the Pacific Ocean
An oil spill in June 2000 threatened tens of thousands of African penguins.
In 2004, the Kenyan ecologist became the first African woman to win the Nobel Peace Prize
How campaigners fought to stop the 'Khian Sea' from off-loading tons of US waste abroad
Julia Butterfly Hill lived in an ancient redwood tree for 738 days to protect it