Palaeontologists make exciting discoveries in southwest Saskatchewan
Palaeontological fieldworkers have unearthed some exciting discoveries in southwest Saskatchewan during the summer.
Dr. Emily Bamforth, a Royal Saskatchewan Museum palaeontologist and curatorial assistant at the T.rex Discovery Centre in Eastend, has been working at a number of sites in the region during the past few months.
“It's been a really fantastic summer,” she said. “We found a lot of really neat things and a lot of very different things too. So definitely we're coming away from this field season feeling great about what we have to work on in the winter and also what we have to look forward to next summer as well.”
She is most excited about finding the skull of an Edmontosaurus, which is a duck-billed dinosaur, at a site near Shaunavon.
“It's only the second skull of this dinosaur that's ever been found in Saskatchewan,” she said. “The first one was found back in the 1920s. So it's been almost 100 years since we found the skull of this animal in this province and it was just a thrill to found this in the field.”
The plant-eating Edmontosaurus lived just before the extinction of dinosaurs and the skull is therefore about 66 million years old. It roamed the Earth the same time as two other large dinosaurs, the herbivorous Triceratops and the carnivorous Tyrannosaurus rex.
“We find a lot of their exploded bones, basically bits and pieces here and there, their limb bones, their vertebra, their ribs, but it's very unusual to find a skull,” she said about the Edmontosaurus discovery. “That's what got us really excited. We knew that they were relatively abundant. So to find a skull to be able to tell us more about the species and about how the animal grew, the age of the animal, things like that, was very exciting.”
There might be even more bones from this dinosaur at the site where it was discovered, but additional fieldwork will have to be done to uncover them.
“We collected the skull and the other part of the skull we call the cranium and one of the upper jaws,” she said. “That was all we collected for this time, but it's likely that if we push the hill back there's going to be more there. That's definitely on the agenda for next summer.”
Fieldwork at another site near Eastend uncovered a mammal fossil of an animal that lived after the extinction of the dinosaurs. Brontotheres were large rhino-like animals that were similar in size to a modern elephant.
This fossil is about 38 million years old and was discovered on a site where Royal Saskatchewan Museum palaeontologists have been working on and off for more than three decades.
“This summer we actually came across a complete or a relatively complete skeleton of a juvenile animal, so sort of a teenager brontothere,” she said. “We always get really excited whenever we find juvenile animals, because they're rare in the fossil record, generally speaking.”
The skeleton of a juvenile animal can help scientists to develop a better understanding of their growth and of the changes that took place during their development and ageing.
“The other neat thing about this story is that we believe that brontotheres were migratory,” she said. “They were moving, just like a lot of animals today, north in the summer and south in the winter, and the juvenile material we have is all about the same age. So we think these animals were migrating through this area at the same time of year and then they basically fell into this fast flowing river and some of them would drown and be deposited, and that's why we found this assemblage of bones.”
The landscape in southwest Saskatchewan looked a lot different 38 million years ago during a geological epoch known as the Late Eocene. It was much warmer with a climate similar to what one will experience today during a visit to the Mississippi River Delta region. There were fast flowing rivers and the lush vegetation was perfect for brontotheres, which were the largest herbivores at that time.
Another interesting discovery took place in Grasslands National Park in August during Fossil Fever, the park's annual public program that provides members of the public an opportunity to participate in palaeontological fieldwork. During the excavation the horn core of a young Triceratops was found, which is about 66 million years old.
“So again, we got excited when we found babies or juveniles in the fossil record,” she said. “Of all the Triceratops we've ever found in Saskatchewan, this is probably the third youngest individual.”
Fieldworkers found a handful of Ankylosaurus teeth, which are about 74 million years old, when they visited a site in the Consul area. A distinctive feature of these plant-eating dinosaurs is the bony armour over their bodies. Fossils were previously collected at this site about 30 years ago.
“It's what we call a vertebrate microsite,” she said. “It's a site that has a lot of really small fossils in it, so fish scales and lizard vertebrae, mammal teeth and things like that, really centimetre scale fossils.”
It is very rare to find any Ankylosaurus material in Saskatchewan, which made this an important discovery.
“One of the questions that we're looking at is why Ankylosaurus are so rare in Saskatchewan, because we don't find any of their bones,” she said. “We don't find the big tail clubs, we don't find the spikes, we don't even find the limb bones or the ribs. ... We know they lived in Alberta, where they're relatively common, and they lived down south in the States around the same time period. We think it's something biological that was excluding them from this area, but we're not sure yet what it is. So that's one of the research questions we're looking at.”
Dr. Bamforth also studies fossil leaves and their relationship to paleoclimate. Another important find this summer was beautifully preserved fossil leaves at a site in Grasslands National Park.
“They look like they fell off the tree yesterday, even though they're 65-66 million years old,” she said. “They're really, really important for understanding ancient life, because they're a very important source of paleoclimate information.”
A fossil leaf assemblage can provide scientists with information about how warm or wet it was, or how dark it was in the winter or how much light there was in the summer.
“So we were really excited to find this particular site,” she said. “It's about a metre and a half above the extinction layer of the dinosaurs. It tells us a lot about what the world was like right after that extinction and also how fast the plant life recovered after that extinction event.”
The fossil leaves are not easy to unearth and on average they only find one new fossil plant site every year.
“They don't conveniently weather out of the ground the way the dinosaur fossils do,” she explained. “You actually have to dig for leaf fossils. They're very fragile and as soon as they're exposed to the air, they fall apart. So you have to actually knock of big blocks of rock to actually see if there are plants in there.”
During the collection process they will use an aerosol spray to consolidate the leaf fossils and they are then carefully packed in tissue paper.
“We have to keep them under controlled conditions in the lab so they don't dry out and start cracking,” she said.
“So they're a little bit more difficult to collect and to preserve than the vertebrate fossils, but a really important source of information. So we like collecting plants.”
Fieldwork was done along the South Saskatchewan River, where ammonites and marine clams were collected from the Cretaceous Bearpaw Formation. This geological formation occurred between 74 and 72 million years ago, when Saskatchewan was covered with a shallow sea.
“It was a sea that actually covered North America from the Arctic Circle to the Gulf of Mexico, and it was warm and shallow,” she said.
“It supported a lot of life. A lot of the marine fossils that we get in Saskatchewan come from this time period, and one of the best places to find fossils from that age is actually along the South Saskatchewan River.”
The two palaeontologists at the T.rex Discovery Centre rely on volunteers and McGill University field students to help them with the labour intensive fieldwork.
“It's moving lots of rock and carrying heavy things,” Dr. Bamforth said.
“So we get a number of students every year. We have a lot of great local volunteers who come out and help us, and for a few of the sites we also had our palaeontology team from Regina, so two other palaeontologists there, came out and helped as well.”
There is an off-season volunteer program at the T.rex Discovery Centre that provides volunteers with an opportunity to learn more about fossils and how to handle them when they are still enclosed in rock.
“We like them to have some experience in our lab before we take them out into the field,” she said.
“We like having people in the field as well, because lots of hands make light work.”
There is still a lot of work ahead for the palaeontologists after the fieldwork season. Fossils have to be sorted, catalogued, and studied.
The T.rex Discovery Centre is hosting a number of Tea and Fossils public events during the fall.
The Saturday afternoon events will give participants an opportunity to do hands-on work with real fossils for an hour, followed by tea, coffee and conversation.
The next Tea and Fossils will be on Oct. 27, starting at 2 p.m.. There will be similar events on Nov. 24 and Dec. 15 at the same time.
Everyone is welcome and no experience is necessary to work with the fossils.
Admission is by donation.