It is estimated that there are 250,000 flowering plants in   

EXIST

today, but thousands of these are still unknown. The 

TROPICS

rainforests are home to    half of the earth's plant species. 

APPROXIMATE

Yet an area of rainforest the size of Austria is being    

THOUGHT

destroyed every year. 

Every day five plants become extinct. This    is worrying

DESTROY

because many medicines are based on plants.

For example, worldwide leukaemia    owe their 

SUFFER

  to chemicals from the flower of the rosy periwinkle; and

SURVIVE

patients breathe    during operations thanks to the

EASE

thornapple. Even the    people sometimes take something

HEALTH

first found in willow bark and now known as aspirin.

Who knows what as yet    weapons against cancer, heart

DISCOVER

disease or AIDS are being    by the ruin of the world

THREAT

rainforests?