There are 4.5m butterflies - brought together over hundreds of years - at London's Natural History Museum. It is the world's biggest butterfly collection.
Here - as the museum brings in hundreds of pupae for its live Sensational Butterflies exhibition on its front lawn - staff have given BBC News access to some of the most precious specimens, normally stored securely away from public view.Continue reading the main story
Blanca Huertas is the butterfly curator at the Natural History Museum and Luke Brown is the museum's butterfly house manager.
Sensational Butterflies can be seen at the Natural History Museum, London, until 15 September 2013.
All images subject to copyright. Music by KPM Music.
Slideshow production by Paul Kerley. Publication date 16 April 2013.
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