By Christine McGourty BBC science correspondent

Millions of preserved creatures from across the world - including some collected by Charles Darwin himself - are going on view at a London museum.

Everybody thinks it's just dinosaurs and stuff out at the front, but it's us in the back that make this place important internationally

Prof Phil Rainbow

For the Natural History Museum, it is little short of a revolution. Most of its vast collection of specimens previously tucked away in dusty cupboards are being brought into the limelight in the new �95m Darwin Centre.

Here, visitors will be able to see the museum's scientists at work for the first time.

The stars of the show include animals collected by Darwin on his 19th Century voyage on the Beagle and some from Captain Cook's expedition on the Endeavour.

	:	In pictures
Inside the Darwin Centre

More recent specimens include a swordfish washed up on a beach near Bristol and a barracuda found in British waters last year.

Explosive atmosphere

There are 22 million specimens in all, stored in 450,000 jars, filling up 27 kilometres of shelf space.

Professor Phil Rainbow, the curator of zoology at the museum, says they will now be stored in far better conditions than previously possible.

Millions of specimens will be seen for the first time

"The old building was very cramped and because of the lack of temperature and humidity control, there was a danger of an alcohol-rich atmosphere which was a fire hazard.

"In the new building, the offices and laboratories are state of the art and will keep the specimens in excellent condition."

Phase One of the project, which involved re-housing all the zoology specimens, is now complete and opens to the public at the end of the month.

Phase Two, which will house the museum's botanical and insect collections - including 28 million insects and six million plants - is due to open in 2007.

Behind the scenes

Professor Rainbow says that in addition to improving conditions for scientists and the collections, the new building will provide visitors with an unprecedented glimpse of the research that goes on behind the scenes.

The public will see scientists at work

"Everybody thinks it's just dinosaurs and stuff out at the front, but it's us in the back that make this place important internationally.

"This is not an exhibition. It's a working building full of scientists and full of collections. We thought it was important that we let our visitors see what we do and why it's important."

Visitors will be taken on tours that include the Darwin Centre's tankroom, which contains 50 stainless steel tanks filled with spirit, housing the largest of the specimens, including a tuna, a shark, a komodo dragon, loggerhead turtles, giant spotted rays - and a rare "living fossil", the coelacanth.

The specimens, such as this flying fish, are preserved in spirit

Around the walls are shelves packed with glass jars up to one metre high, stuffed full of preserved creatures ranging from porcupines to a wolf, monkey and snakes.

Oliver Crimmen, the museum's fish curator, says: "These specimens were the most awkward things to house. Some were kept in a motley collection of containers under stairwells and in cupboards.

"Now, they're much more accessible and there's an automated hoist to take the lids off the tanks and a ventilated dissection bench. Everything is state-of-the-art."

'Darwin would approve'

Professor Steve Jones, of University College London, who has had a preview of the new centre, says: "I think for the public this magnificent building is a reminder that there is more to biology than natural history programmes.

The largest items, such as this komodo dragon, are kept in tanks

"Biology is a science, however disparate, and a science first recognised by Charles Darwin. And this centre is a monument to that fact."

A biologist from the Natural History Museum, Sandy Knapp, says that Charles Darwin himself would have been delighted. "I think he would have liked it.

"His science was based on evidence and these specimens are what we base our science on today.

"It's one of our duties to hold these specimens in trust for the next generation of scientists. And this new centre will help us to preserve them better than we could have hoped to do before."