July 9, 2014
Fossil Of Tiniest Known Hedgehog Species Found In British Columbia
Gerard LeBlond for redOrbit.com - Your Universe Online
The Silvacola acares is a tiny hedgehog species that lived roughly 52-million-years ago, during the Eocene Epoch. Its fossil remains were recently identified by a University of Colorado Boulder-led team working in British Columbia. Along with the tiny hedgehog, the fossils of a tapir-like animal were also discovered.
A paper on the discovery of these two ancient mammals is being published today in the Journal of Vertebrate Paleontology. Study co-authors include Research Scientist Natalia Rybczynski of the Canadian Museum of Nature in Ottawa, Ontario, and Professor David Greenwood of Brandon University in Brandon, Manitoba.
The hedgehog's scientific name means "tiny forest dweller," said lead author, CU-Boulder Associate Professor Jaelyn Eberle of the geological sciences department.
The creature was only about two inches long and is a new genus and species to science.
"It is quite tiny and comparable in size to some of today's shrews," Eberle said.
Hedgehogs have quills, but did this tiny creature?
"We can't say for sure, but there are ancestral hedgehogs living in Europe about the same time that had bristly hair covering them, so it is plausible Silvacola did too."
In North America over the last several years, hedgehogs have been increasing as family pets. The most common one obtained is the African pygmy hedgehog which is about four times the size of the Silvacola.
The fossils were found at the dig site Driftwood Canyon Provincial Park, located in north-central British Columbia, Canada. Eberle believed that 52 million years ago the region had a rainforest environment. The fossil plants indicate the region during the Eocene Epoch period seldom had freezing temperatures and the climate was similar to Portland, Oregon, which is 700 miles south.
According to Eberle, since the extinction of the dinosaurs 66 million years ago, the Earth has gone through many changes in climate. During the Early Eocene Epoch, it was one of the warmest periods on Earth. The animals during this period were quite different than those of today.
"Within Canada, the only other fossil localities yielding mammals of similar age are from the Arctic, so these fossils from British Columbia help fill a significant geographic gap," said Rybczynski. She also stated that other fossils have previously been discovered in Wyoming and Colorado from the same era.
The fossils were embedded in the surrounding rock, so instead of trying to remove them, the team used an industrial high-resolution CT scanner to study, preserve and protect the fossils from damage. Hedgehogs of today are restricted to Europe, Asia and Africa.
The other mammal discovered at the site, Heptodon, is an ancient relative of modern tapirs. It is a small mammal resembling a rhino but without a horn.
"Heptodon was about half the size of today's tapirs, and it lacked the short trunk that occurs on later species and their living cousins. Based upon its teeth, it was probably a leaf-eater, which fits nicely with the rainforest environment indicated by the fossil plants at the site," Eberle said.
This site is known for its insect, leaves, and fish fossils, but has never produced mammal fossils before.
"The discovery in northern British Columbia of an early cousin to tapirs is intriguing because today's tapirs live in the tropics. Its occurrence, alongside a diversity of fossil plants that indicates a rainforest, supports an idea put forward by others that tapirs and their extinct kin are good indicators of dense forests and high precipitation," Eberle said.
"Driftwood Canyon is a window into a lost world, an evolutionary experiment where palms grew beneath spruce trees and the insects included a mixture of Canadian and Australian species. Discovering mammals allows us to paint a more complete picture of this lost world," said Greenwood.
"The early Eocene is a time in the geological past that helps us understand how present-day Canada came to have the temperate plants and animals it has today. However, it can also help us understand how the world may change as the global climate continues to warm," Greenwood added.
Image 2 (below): This image depicts fossil-bearing sediments at the 'North Face' fossil site in Driftwood Canyon Provincial Park, British Columbia, where the extinct hedgehog fossils were collected. Credit: Photo by Dave Greenwood.