Thursday, February 14, 2013

Window on the Ancient Past

A couple of hours south of St. John's, the community of Portugal Cove South is the gateway to two important sites, Cape Race -- the Marconi station where the last signal from the Titanic was received -- and Mistaken Point, where the fossils of the Ediacaran biota, Earth's oldest complex lifeforms, can be found. This site is a true treasure, considered significant enough to be featured in Sir David Attenbrough's presentation, First Life. You'll see his visit to Mistaken Point at minutes 23:25 to 36:00.  All visitors to the fossil site must be accompanied by trained interpreters; a guided visit takes place each day, starting at the Interpretation Centre for the Mistaken Point Ecological Reserve.  The site is reached on foot, by way of a coastal trail that leads to the sloping
sandstone and mudstone layers that house the deposit. Some 560 to 575 million years ago, this area was at the bottom of a deep ocean, far beyond the level to which light could penetrate. The Mistaken Point Assemblage is made up of over 30 soft-bodied species that existed millions of years before animals developed skeletons.  They were preserved by a series of undersea volcanic eruptions that covered them completely in layers of ash, and eventually the seafloor containing those layers was thrust upward to its present position.  While other deposits of a similar age exist, the grouping of lifeforms at Mistaken Point is unique. This rugged and
often fog-shrouded coastline is now on a list of nine potential UNESCO World Heritage Sites within Canada.

Much of our knowledge of Ediacaran fossils at this remarkable site comes from the research of Dr. Guy Narbonne, Professor and Research Chair in the Department of Geological Sciences and Geological Engineering at Queen's University in Kingston, Ontario.  Dr. Narbonne is a world-renowned specialist in the origin of animals, whose description of the unusual fractal nature of the Ediacaran physiology was hailed as one of the top 100 science discoveries of 2004.

The fossil beds are located at the edge of the Eastern Hyper-oceanic Barrens ecoregion, noted for its distinctive low-growing vegetation and balsam fir tuckamore.  The walk to the fossil beds is approximately 45 minutes in each direction over rolling and uneven ground, with two stream crossings.  Be prepared for the cool, damp weather that's common to the area.

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