Sharks that lived off Edinburgh beach 'brought to life' once again
The terrifying sea beasts lived some 335 million years ago off the coast of what is now Edinburgh.
Now the very early sharks that roamed waters off Wardie Beach to the north of the city have been 'brought to life' in the United States using breakthrough scientific techniques,
Dr Stig Walsh, Senior Curator of Vertebrate Palaeobiology at National Museum of Scotland, said the fossilised remains of the sharks had been collected from Wardie Beach since the 19th Century but that is only now possible to reconstruct their skeletonsusing new X-ray techniques.
A new study just published in the journal Science Advances uses these cutting-edge techniques to shed new light on how the early sharks existed.
Dr Walsh, writing on the National Museums of Scotland blog, said: "Piecing together how extinct animals lived and moved is no easy task. Fossils are rarely complete, so important information is usually missing.
"Even when fossil skeletons are complete, they are often crushed and the individual bones are no longer in the position they would have been in life.
" All of these uncertainties make it difficult to imagine how the bones would have moved together in a three-dimensional sense.
"Fortunately, fossils found in some locations are very well preserved and quite complete, usually because of the environment in which the animal died and was buried. Wardie Beach in north Edinburgh is one such site. "
The fossil fishes at Wardie Beach are so well preserved given they were encased in hard 'nodules' when they died.
Now, X-ray computed-tomograhy (X-ray CT) means there is no need to smash open nodules, usually with a large hammer, to find out what might lie inside.
National Museums of Scotland holds a large collection of Wardie nodules, most of which are stored at the National Museums collections Centre in Granton, not far from the beach where they were found.
Professor Mike Coates of the University of Chicago, who is also a Research Associate at National Museums Scotland, set about applying the use of X-Ray CT technology to look inside the nodules held in Edinburgh
A large number of specimens were sent from Scotland to Chicago to investigate.
One nodule was of particular interest and looked like the head of a large snake, complete with eyes and nostril, Dr Walsh said.
He added: "Mike was quick to recognise the potential of X-ray CT analysis for the unbroken Wardie nodules, and set to work to find out what secrets they might hold.
"These specimens turned out to be an important addition to science. Although the skeletons they contained were flattened, Prof. Coates’ team was able to reconstruct the cartilages into the positions they would have been in life.
Dr Walsh said the ‘snake head’ nodule proved to be particularly interesting and contained the head of a shark Trystichius arcuatus shark.
After its head was reconstructed, researchers were surprised to find that this particular shark had an advanced method of feeding using suction.
"Up to that point, the first evidence of this kind of feeding adaptation in bony fishes was some 50 million years later," Dr Walsh said.
He added: "Many of the Wardie nodules Prof. Coates investigated had been stored in our collections for decades, waiting for new technology that would unlock their secrets. I wonder which of our specimens will provide the next scientific advance, perhaps with some new technology that has yet to be imagined?"
A version of this article first appeared on the National Museum of Scotland blog.