450-million-year-old armour-plated creature discovered in Canada's capital
(Toronto, Ontario – March 19, 2010) – One of the world’s rarest fossils has been discovered in downtown Ottawa, Ontario. The 450-million-year-old fossil contains the complete skeleton of a plumulitid machaeridian, one of only eight such specimens known. Plumulitids were annelid worms - the group including earthworms, bristleworms and leeches - today found everywhere from the deepest sea to garden soil. Although plumulitids were small, they reveal important evidence about how this major group of organisms evolved. “Such significant new fossils are generally discovered in remote areas of the globe, requiring difficult journeys and a bit of adventure to reach them,” notes Jakob Vinther of Yale University, lead author of the paper describing the specimen. “Not this one though. It was found in a place that has an address rather than map co-ordinates! As far as we can determine, the excavation at the address on Ottawa’s Albert Street was undertaken to build an underground parking facility on the site of the Word Exchange Plaza.”
The fossil is described by Vinther, and David Rudkin of Toronto’s Royal Ontario Museum(ROM), in the current issue of the journal Palaeontology. It was Rudkin who first recognized its scientific significance. In his words: “This nifty little specimen first came to my notice in 1997 when I received a letter from an amateur fossil collector in Nepean, Ontario. In prospecting for fossils in rock from a temporary building excavation in Ottawa, one of his fellow collectors had turned up a small block containing a complete trilobite, but next to it was something else. The collector also included a slightly fuzzy, but very intriguing photo. The mystery fossil was clearly not another trilobite. Although I couldn't be certain, I thought it might be some sort of annelid worm with broad, flattened scales. My correspondent had since acquired the specimen and generously agreed to loan it to the ROM for study. When I received it, I realized immediately that it was a complete, fully articulated machaeridian- the first I had ever seen.
At that time, it was not known that machaeridians were annelids. “The correspondent was happy to donate the specimen to the ROM in exchange for a promise that I’d someday publish the discovery.”
It was not until 2008 that Rudkin’s hunch was confirmed when a team of palaeontologists, including Yale’s Vinther, described new machaeridian fossils from remote mountain localities in Morocco, revealing their relationship to annelid worms. Rudkin and Vinther agreed to work together to interpret the Ottawa specimen, and the results of their collaboration are published in the current issue of Palaeontology, (Volume 53, Part 2), released on March 15, 2010 (pre-published online February 23, 2010).
Plumulitid machaeridians look like modern bristleworms with stout walking limbs that bear long bundles of bristles; however, on their backs, they carried a set of mineralized plates. According to Vinther, “The plates themselves were rigid, but they could move relative to one other, providing plumulitids with a protective body armour similar to the flexible metal armour invented by humans 450 million years later. Machaeridian body armour is unique among annelids and probably helped them to succeed as ubiquitous components of marine ecosystems for more than 200 million years.”
With the publication of this paper, Rudkin is finally able to make good on his promise. “It’s great to be able to acknowledge the amateur palaeontologists who found the fossil,” says Rudkin. “Regrettably, I lost contact with the gentleman who facilitated the fossil donation and numerous enquiries as to his whereabouts have come up empty. I hope he somehow gets wind of all this.”
Notes to Editors
1. The paper “The first articulated specimen of Plumulites canadensis (Woodward, 1889) from the Upper Ordovician of Ontario, with a review of the anterior region of Plumulitidae (Annelida: Machaeridia),” by Jakob Vinther and David Rudkin, is published in the current issue of Palaeontology. Copies of the paper can be obtained on request from Jakob Vinther or David Rudkin
2. Jakob Vinther of the Department of Geology and Geophysics, Yale University, New Haven, CT 06520, USA, can be contacted at jakob.vinther@yale.edu or at 203.823.8483; David Rudkin of the Department of Natural History (Paleontology), Royal Ontario Museum, Toronto, ON M5S 2C6, Canada can be contacted at davidru@rom.on.ca or at 416.586.5592
3. Palaeontology is published by the Palaeontological Association, a registered charity that promotes the scientific study of fossils and one of the world's leading learned societies in this field. For further information about the association and its activities, or for forthcoming papers of interest in Palaeontology, contact Publicity Officer Mark Purnell at publicity@palass.org
4. High resolution versions of the images above can be obtained from http://publicity.palass.org/images/plum&trilobite.jpg
Other Information
The ROM has historically been a repository for important fossils from Ontario Among many other important specimens, the ROM’s Invertebrate Palaeontology section holds numerous Ontario fossils from the collection of ROM founder (and amateur palaeontologist), Sir Byron Edmund Walker. These were acquired by Walker in the late 19th century and include unique type specimens of important fossil taxa. The ROM also holds the historic research collections made by former ROM Museum of Palaeontology Director William Arthur Parks and Curator Madelaine Fritz, both of whom published extensively on the fossils of Ontario. More recently, the ROM has assembled exceptional suites of fossil trilobite, eurypterid and echinoderm specimens from Ontario, for exhibit in the planned Peter F. Bronfman Gallery of Early Life.