Millions of water voles, whales and wildcats are set to drop through letter boxes across the UK in the coming weeks - as the Royal Mail highlights the struggle for survival facing some of Britain's wild mammals.
As part of the 2010 International year of Biodiversity, 10 new First Class stamps show creatures for whom the future is by no means secure - as the Chief Executive of The Mammal Society, Marina Pacheco, explains.
Images courtesy Royal Mail, Science Photo Library and Getty Images. Music courtesy KPM Music.
Slideshow production by Paul Kerley. Publication date 13 April 2010.
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