Tuesday, 3 May 2011
Next time you visit the Natural History Museum in London, turn left at the dinosaur's tail and wander through to the Darwin Centre and The Cocoon. Last Thursday, I took part on the Spirit Collection Tour there. Spirit does not refer to ghosts or whisky, but rather to the samples that are preserved in a mixture of ethanol and methanol, IMS. Though, to be fair, when early collectors ran out of pure alcohol, brandy or rum provided a simple solution until the specimens were returned home.
The visitors area of the Darwin Centre displays several hundred animals and plants in their tastefully lit jars. The rest of the building, from it's basement to the floors above, houses 22 million of the 70 million or more specimens of the worlds flora and fauna for the future. Yet this is not simply a giant pickle collection to be sniffed at (especially as the IMS is harmful if inhaled in quantity). The building also has laboratories and scientists. They continue to gain real results in our understanding of life on earth from this valuable resource.
The Spirit Collection Tour takes a small group of eight visitors behind the scenes. Our guide, Jessica, was a working scientist who specialised in mammals. Luckily for us, she was also trained in communicating with the lay audience.
We went down into the basement; first stop, the flesh eating beetles. Not a nightmare, but insects put to practical use. These are nature's waste removal system, getting rid of carrion. Safely kept in the laboratory, they strip flesh from samples, leaving the skeleton. This avoids the use of hazardous chemicals and an otherwise messy, smelly, dangerous job for the scientist. The beetles were cleaning a killer whale tooth. You can see them working for yourself on the flesh-eating beetle cam. Let's hope someone cleans the lens and sorts out the focus in the meantime.
Then we came to the chilled rooms housing rows upon rows of cabinets with samples under lock and key. So valuable to science that they were evacuated to caves outside of London during WWII. Further on we entered to the room containing the large specimens. I had remembered Archie, the giant squid from a previous visit. As long as a London bus, the tentacles were covered in suckers. This time I saw that each sucker had a wicked circle of teeth, to maximise grip when tackling prey or battling with their predator, the sperm whale.
Amongst the many specimens stored there were a few in a special cabinet. These were samples originally collected by Darwin on the Voyage of the Beagle. Amonstthem was the shell of his pet tortoise from the Galapagos Isles, lost for over a century until found again in the 1980s.
But why are these collections so important?
First, Whenever a new species was or is discovered, a physical record of a typical type specimen is made. This type specimen can be compared with later finds of the same or similar organisms as an important guide for accurate identification. Some of these samples are so important, that they will travel across the world on loan, to help naturalists with their work there.
Second, of the tens of millions of animals and plants stored, many were preserved, catalogued and simply put into storage for later. Work still needs to be done to understand them further.
Third, preservation in IMS has kept the DNA intact so that modern DNA technologies can be used to gain even more knowledge.
Is this really relevant to you or me? Yes! There are some really practical applications, as well as increasing our general understanding of life on earth. For example, later when I walked through the through the Cocoon, which houses the insect collections, I stopped at the window to the working lab. A scientist was studying New Forest blow flies, talking to us as she worked and also answering questions. We could actually see the work being done under the microscope. I learnt that blow flies can apparently be important in murder cases; in terms of giving the police and courts an estimate of how long a body has lain since death. Local blow fly species might also help by giving geographical information; was the body moved after the murder, for example.
So when you next walk up the steps and into the glorious Victorian main hall of the Natural History Museum, do not just come to look at the exhibits. Take one the many opportunities to talk to and interact with real scientists who work there on our behalf. The museum is not just a collection of static displays, it is also a major centre for increasing our knowledge – and willing to tell you about it in terms that you and I can understand.