Fossils abound: ‘Epic’ new Burgess Shale site in Canada’s Kootenay National Park

Yoho National Park’s 505-million-year-old Burgess Shale — home to some of the planet’s earliest animals, including a very primitive human relative — is one of the world’s most important fossil sites. Now, more than a century after its discovery, a compelling sequel has been unearthed: 42 kilometres away in Kootenay National Park, a new Burgess Shale fossil bed has been located that appears to equal the importance of the original discovery, and may one day even surpass it.A paper published today in the scientific journal Nature Communications describes Kootenay National Park’s new ‘Marble Canyon’ fossil beds for the first time. The authors suggest that the area and its extraordinary fossils will greatly further our understanding of the sudden explosion of animal life during the Cambrian Period.The find was made in the summer of 2012 by a team from the Royal Ontario Museum (ROM, Jean-Bernard Caron), Pomona College (Robert Gaines), the University of Toronto (Jean-Bernard Caron, Cdric Aria), the University of Saskatchewan (Gabriela Mngano) and Uppsala University (Michael Streng).”This new discovery is an epic sequel to a research story that began at the turn of the previous century. There is no doubt in my mind that this new material will significantly increase our understanding of early animal evolution,” said Dr. Jean-Bernard Caron, Curator of Invertebrate Paleontology at the ROM, Associate Professor at the University of Toronto and the study’s lead author. “The rate at which we are finding animals — many of which are new — is astonishing, and there is a high possibility that we’ll eventually find more species here than at the original Yoho National Park site, and potentially more than from anywhere else in the world.”In a short 15-day field season, the researchers collected thousands of specimens representing more than 50 species, several of which were new to science. Incredibly, many of the species previously known from Yoho are better preserved in Kootenay, retaining very fine, never-before-seen anatomical details that are important for understanding the shape of the animal ‘family tree.’The new site parallels Yoho in its spectacular richness of arthropods, a group that today represents more than 80% of all living animals, including insects, spiders and lobsters.Another curious similarity between Marble Canyon and the original discovery is that both sites would still be buried today if not for the dedicated exploratory work of scientists.In 1909, world-renowned paleontologist Charles Walcott spent a summer exploring Yoho National Park’s mountainous topography in search of hidden treasures, only to stumble upon what he would later name the Burgess Shale on the final day of his field season on August 29. Similarly, in 2012, a ROM field expedition led by Caron spent part of their summer in search of the next big paleontological discovery.”We were already aware of the presence of some Burgess Shale fossils in Kootenay National Park,” said Dr. Robert Gaines, a geologist from Pomona College, who along with Caron and colleagues had spent August 2008 at a much smaller fossil deposit in the park located near Stanley Glacier. “We had a hunch that if we followed the formation along the mountain topography into new areas with the right rock types, maybe, just maybe, we would get lucky — though we never in our wildest dreams thought we’d track down a motherload like this.”Just like Walcott a century before, a hunch led Caron and his team to a talus slope high in the Canadian Rockies. …

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‘International beam team’ solves Martian meteorite-age puzzle

July 24, 2013 — By directing energy beams at tiny crystals found in a Martian meteorite, a Western University-led team of geologists has proved that the most common group of meteorites from Mars is almost 4 billion years younger than many scientists had believed — resolving a long-standing puzzle in Martian science and painting a much clearer picture of the Red Planet’s evolution that can now be compared to that of habitable Earth.In a paper published today in the journal Nature, lead author Desmond Moser, an Earth Sciences professor from Western’s Faculty of Science, Kim Tait, Curator, Mineralogy, Royal Ontario Museum, and a team of Canadian, U.S., and British collaborators show that a representative meteorite from the Royal Ontario Museum (ROM)’s growing Martian meteorite collection, started as a 200 million-year-old lava flow on Mars, and contains an ancient chemical signature indicating a hidden layer deep beneath the surface that is almost as old as the solar system.The team, composed of scientists from ROM, the University of Wyoming, UCLA, and the University of Portsmouth, also discovered crystals that grew while the meteorite was launched from Mars towards Earth, allowing them to narrow down the timing to less than 20 million years ago while also identifying possible launch locations on the flanks of the supervolcanoes at the Martian equator.More details can be found in their paper titled, “Solving the Martian meteorite age conundrum using micro-baddeleyite and launch-generated zircon.”Moser and his group at Western’s Zircon & Accessory Phase Laboratory (ZAPLab), one of the few electron nanobeam dating facilities in the world, determined the growth history of crystals on a polished surface of the meteorite. The researchers combined a long-established dating method (measuring radioactive uranium/lead isotopes) with a recently developed gently-destructive, mineral grain-scale technique at UCLA that liberates atoms from the crystal surface using a focused beam of oxygen ions.Moser estimates that there are roughly 60 Mars rocks dislodged by meteorite impacts that are now on Earth and available for study, and that his group’s approach can be used on these and a much wider range of heavenly bodies.”Basically, the inner solar system is our oyster. We have hundreds of meteorites that we can apply this technique to, including asteroids from beyond Mars to samples from the Moon,” says Moser, who credits the generosity of the collectors that identify this material and make it available for public research.

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