Miners used to take canaries into unfamiliar shafts to act as early warning systems for the presence of poisons. Today, climate scientists have their own canaries - amphibians. Amphibians - the frogs, toads and salamanders - are particularly susceptible to environmental changes because of their fondness for water, and their porous absorbent skins. They are usually the first to feel the impact of environmental changes.
And feel it they have. They are one of the most threatened groups of animals and one in three species currently faces extinction. The beautiful golden toad (right) was one of the first casualties and disappeared for good in 1989. Even though they are less glamorous than tigers, pandas or polar bears, amphibians are a top priority for conservationists.
The usual factors - introduced predators and vanishing habitats - are partially to blame, but many populations have plummeted in parts of the world untouched by ...