July 26 , 2016
by Cassie Williams
A "hugely successful" dig along Nova Scotia's Bay of Fundy has unearthed a treasure trove of 200-million-year-old fossils.
Tim Fedak, the curator of the Fundy Geological Museum in Parrsboro was on the hunt for small bones of lizard-like creatures from the Jurassic period.
He and his team scoured the red sandstone cliffs of Wasson Bluff for seven days and collected 25 specimens.
Among those, there were five bone fragments, portions of the skull of lizard-like animals called sphenodontids. The animals are very small, about the size of a mouse.
The fossils belonged to ancient ancestors of a living fossil called a sphenodon, found in New Zealand. Living fossils are organisms that have remained relatively unchanged in many millions of years and whose close relatives are usually extinct. The coelacanth is a relatively well-known example.
The spot where Fedak and his team were working is important for two reasons: erosion is constantly unearthing new specimens; and the creatures buried here died after one of the largest mass extinction events in Earth's history.
"Their world had just undergone one of the largest mass extinctions at the end of the Triassic period," he told CBC's Information Morning Cape Breton.
"So these animals whose bones are found in this red sandstone along the shores of Parrsboro … they represent the survivors of this mass extinction.
"By collecting all of the specimens that we can, we're able to establish a really rich record of what survived that mass extinction and perhaps start answering questions about why they have."
Scientists estimate the mass extinction at the end of the Triassic period 200 million years ago killed off between 70 and 80 per cent of all species alive at that time.
What caused the Triassic-Jurassic extinction ?
It's believed that the supercontinent Pangea started to move apart. As it did, it gave way to the Atlantic Ocean as the mid-Atlantic ridge opened up. Also, North America and South America started to pull away from Africa and Europe. All that movement caused a huge amount of magma or molten rock to come to the surface.
The magma released huge amounts of gas into the atmosphere, causing rapid global warming that was the likely trigger for this mass extinction.
Feedak said because of the constantly changing landscape there is always potential for exciting discoveries along the sandstone cliffs of Parrsboro.
He said he's especially excited by the prospect of finding more bones belonging to a small meat-eating dinosaur. So far, just the tip of the creature's snout has been found.
http://www.cbc.ca/news/canada/nova-scotia/parrsboro-fossil-cliffs-discovery-1.3689214
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