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Behind the scenes

2 Posts tagged with the fossil tag

First things first - I know our new Stegosaurus is no longer behind the scenes, and now grandly stands at the Museum's Exhibition Road entrance. I know that a lot has already been written and reported about it, so there can't be much more left for me to reveal. But the opportunity to write about the acquisition of an internationally significant and scientifically invaluable new specimen doesn't come along every day. In fact, it rarely comes along for the Museum, with this being the first near complete dinosaur fossil to be acquired by us in the past 100 years. So for that reason, I had to pick our new fossil skeleton as December's Specimen of the Month.


However, there is a 'behind the scenes' aspect to this piece. I was one of the few members of staff lucky enough to actually get behind the hoarding which protected the view of the construction process from the public while the Stegosaurus was being assembled. On that Monday, 1 December, looking down from the first-floor balcony of the Earth galleries (where an interactive digital display, 3D printed touch objects and specimen interpretation now stand), it was impossible not to get excited by the magnitude of the occasion. It was momentous not just for the Museum, but for any human being with even a passing interest in nature and history.


Much to the varied amusement/excitement/jealousy of my friends and followers, I tweeted:

Today at work I'm watching the (re)construction of a dinosaur skeleton #standard #museumlife @NHM_London

— Amy Freeborn (@amyfreeborn) December 1, 2014


My view from the balcony before the (re)assembly commenced. Of course, I couldn't tweet this, or any subsequent pictures, until the 22.00 embargo on Wednesday 3 December had passed.


Things kicked off around 10.45, as senior conservator Lu Allington-Jones attached the dinosaur's feet. Then she was joined by our dinosaur expert Prof Paul Barrett and they both slipped the left tibia into place.


Lu and Paul install the first major Stegosaurus bone of the build - the tibia, or shin bone.


The bones are supported by a specially-designed steel armature. Surfaces of the armature in contact with the skeleton are cushioned to prevent vibration damage. The supporting plinth, which handsomely rises up under the dinosaur's tail, is also designed to dampen vibration from visitor footfall, as well as external traffic and building works.


Once the legs and pelvis were in place, it really was quite amazing to see how fast the neck, spine, ribs and tail then came together. The whole thing was complete - topped out with the final of the four tail spikes - in under four hours. But, Paul said, it wasn't their quickest time:

We did mount the skeleton on three earlier occasions behind the scenes, partly to test that the armature was strong enough in the right places. We can assemble the skeleton in about two hours, but the mounting in the Earth Hall took twice that time as the plinth made it a little more awkward to work around the frame and we needed the Genius lift to get to some parts that we could previously reach from the floor or a regular ladder.


Watch this time-lapse video created on 1 December to see just how impressive the build process was, as four hours becomes about 24 seconds:



Senior curator Tim Ewin, who was mostly responsible for mounting the large back plates and tail spikes, explained of his contribution:

The plates are both heavy and large but very thin and fragile. It was like trying to stack bone china on its thinnest point!


Owing to the way the armature was constructed, it was not as simple as just plonking the bones in place either. Each plate almost invariably had its own unique technique to getting into the right position so it was properly supported and could not jump out and smash itself, other remains, or onto the viewing public. This involved trying a variety of approach directions, rotations and physically moving some of the supports out of the way for each element.


This was not so bad for the more robust, smaller and lighter elements, such as the vertebrae, but was really butt-clenching when it came to trying to install the largest plates at full stretch whilst 12 feet off the ground. Fortunately, there were no breakages, although several took a few goes and a little rest! I was, however, very relieved when we had finished.


Indeed, the whole team in the Earth Hall was relieved when that final fossil bone was put into place, and a spontaneous round of applause broke out. For me, and everyone else, it really was a proud moment to be part of the Museum.



Tim affixing the final Stegosaurus bone, seconds before applause broke out at the completion of the assembly.


Lu told me that the tail spikes are known collectively as the 'thagomizer' that, Tim revealed, is actually a term that originated from a Far Side cartoon. He directed me to Wikipedia, where it says:

The term "thagomizer" was coined by Gary Larson  in a 1982 Far Side comic strip, in which a group of cavemen in a faux-modern lecture hall are taught by their caveman professor that the spikes on a Stegosaur's tail are so named 'after the late Thag Simmons'.


The term was picked up initially by Ken Carpenter, a paleontologist at the Denver Museum of Nature and Science, who used the term when describing a fossil at the Society of Vertebrate Paleontology Annual Meeting in 1993. Thagomizer has since been adopted as an informal anatomical term.


Vital Stegosaurus statistics:
  • Our specimen is a Stegosaurus stenops.
  • It is the first complete dinosaur specimen to go on display at the Museum in about 100 years.
  • It is 560cm long, 290cm tall, and composed of around 300 bones.
  • Its 19 back plates and four tail spikes form the most complete set ever discovered.
  • It is nearly complete, missing only the left arm and base of the tail, as well as a few smaller bones from the hands, toes and tail.
  • It is the best preserved and most complete of only about six Stegosaurus skeletons in the world.
  • It's the only Stegosaurus in a public collection outside the USA.



Following the assembly, I was finally able to tweet at 22.01 on Wednesday 3 December:

We got a new dinosaur at work! @NHM_London #Stegosaurus

— Amy Freeborn (@amyfreeborn) December 3, 2014



I received an email recently from one of my contacts in the Museum's library which simply said: 'Zoe Hughes has a doorstop with an interesting story'.


Intrigued, I fired off an email to fossil invertebrates (Brachiopods and Cephalopods) curator Zoe and made a date to meet her to talk about the doorstop. But we would soon discover that this was just the beginning of the story.


The item in question was a very heavy iron cast of a brachiopod, Spirifer striata, that had been found in the roof of a cave in Derbyshire by fossil collector William Gilbertson. From there the fossil came into the possession of Edmund Garwood, a professor of geology and mineralogy. The fossil was then cast in iron by a member of the Slade School of Art, part of University College London.


Before we go any further, let me briefly explain what a brachiopod is, because I didn't know before Zoe told me. A brachiopod is a sea-dwelling creature. Most anchor themselves to the ocean floor with a worm-like pedicle (or 'arm foot'; literally brachio = arm and poda = foot). Some cement themselves to stones and shells, others have spines which anchor them and some just rest on the ocean floor. Originally thought to be part of the mollusc family which includes mussels and clams, it was later discovered that brachiopods were their own phylum (the taxonomic rank below kingdom and above class). On the outside, brachiopoda resemble bivalve molluscs in that they're comprised of two shells (also known as valves), but inside, they're orientated top to bottom instead of left to right, and feed in a different way. Brachiopods are one of the oldest animals found in the fossil record, and were most abundant in the Paleozoic era, around 250-500 million years ago. There are 30,000 species of brachiopods described, but only around 385 of those occur today.


Now, back to the story. Upon the death of Professor Garwood in 1949, the cast iron brachiopod was given to Helen Muir-Wood, who had carried out post-graduate research on Palaeozoic brachiopod faunas with Garwood at University College London. Muir-Wood worked at the Museum (then the British Museum of Natural History) from 1922 until she retired from her role as curator of the Brachiopoda in 1961. She was the first woman to reach the rank of Deputy Keeper of Palaeontology at the Museum, and (as far as we know) the first to use the brachiopod cast as a doorstop. When she retired, she took the cast home with her to Findon, from where it was recovered after her death in 1968 by brachiopod curator Ellis Owen.


Owen was the custodian of the brachiopod cast until his retirement in 1983, at which time he passed it to Howard Brunton (another curator of the Brachiopoda) who wrote the label that sits in the box in which the cast is housed today, where it comes under the remit of Zoe Hughes.


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The cast iron brachiopod, formerly used as a doorstop.



And that brings the story back to the present day. At least it did at the point I first began writing this blog. But then a few days later I received a rather excited email from Zoe.

I've just found the actual specimen the cast was taken from! I never imagined that I would, as there's no specimen info with it. It was just a lucky find. I happened to open the particular drawer it was in on a tour this morning!

But that wasn't all, she said.

The brachiopod is part of the Davidson collection, which is a very important historical collection. Thomas Davidson wrote a series of monographs charting British brachiopods. And even more excitingly, this brachiopod is figured in one of the monographs. Plus we have Davidson's original notebooks with the initial notes and drawings he created to write the final monographs.

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The original brachiopod fossil from which the cast was made.



It really was an extraordinary and serendipitous find, which has added a new chapter to the 'doorstop with an interesting story'.


Both specimens - the original fossil and the cast - have now been officially registered in the Museum's digital database in recognition of their scientific, and artistic, merit (specimen number NHMUK PI B 321, to be precise), and housed together in our vast collection. It marks a satisfying conclusion to a tale that spans several generations of scientists and more than 120 years of Museum history.


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Thomas Davidson's sketches of the brachiopod fossil (left), and the illustrations that appeared in his book The Monography of British fossil Brachiopoda (right).