In 2004, scientists in the Yukon discovered a rare and surprising remnant of the Pleistocene: an Ice Age meadow. And some of the grass, although at least 30,000 years old, was STILL GREEN.
[Fossil grass below layer of tephra at Gold Bottom Creek, part of a 30,000-year-old grassy meadow discovered in 2004, from Ice Age Klondike, courtesy of the Government of Yukon. To see a picture of some of the green grass, please see page 33.]
In Ice Age Klondike, Dr. Grant Zazula and Dr. Duane Froese explain that this layer—at least 40 meters long–was buried by volcanic ash, or ‘tephra’.
[The layer of tephra is the whitish colored portion toward the bottom; 30,000-year-old tephra, image courtesy of the Government of Yukon.]
Few places in the world offer us such a concentrated wealth of information about the Pleistocene, and the Yukon is one of them.
“There are a lot of common animals like woolly mammoths and bison and horses that we find all the time,” Dr. Zazula said. “But it’s really exciting when we find the bones or the fossils of the rare species, things like camels, or short-faced bears, or lions. Probably for every 500 bones we find, we might find one bone of a carnivore.”
[Susan Hewitson holding an Ice Age lion humerus, courtesy of the Government of Yukon.]
[Ice Age lion mandible, courtesy of the Government of Yukon.]
“I think that one of the things that has really been exciting for me,” he offered, “is that, in the last 10 years, the field of ancient genetics has really taken off in terms of being able to extract DNA from Ice Age bones, then study the details of evolution and how these animals are related to one another.”
[Geneticist Beth Shapiro examines a partial upper jaw bone of a Yukon horse emerging from the frozen mud at Quartz Creek, from Ice Age Klondike, courtesy of the Government of Yukon.]
[Yukon horse jaw uncovered by placer miners on Quartz Creek near Dawson City, from Ice Age Mammals of Yukon, courtesy of the Government of Yukon.]
“[The Yukon is] one of the best places in the world to do that because of the bones being found in permafrost. [There are] so many Ice Age bones that are being found, and they’re really accessible.
“So we work really closely with the geneticists all the time; we’re working on all kinds of different projects together. It’s nice to be able to collaborate with a field like that and make fossils from the Yukon available for study.”
[Geneticist Mathias Stiller with tusk found in the muck at Quartz Creek, courtesy of the Government of Yukon.]
This author writes from an area within the United States that is fossil-poor (finding one mastodon tooth is an enormous deal, and most years pass without a single reported fossil). In comparison, the amount of fossil bones found in the Yukon staggers the imagination. But that is not all that the Yukon has to offer.
Even those not generally interested in paleontology get excited when they see or hear about mummified Ice Age animals. There is something so much more dramatic, that much more intriguing, about seeing an extinct animal in the flesh.
Dr. Zazula was frank about being slightly envious of Siberia’s wealth in that domain. Outside of Blue Babe, a steppe bison carcass found in Alaska, the most spectacular mummified animals have been found on the other side of the world.
And yet, one cannot ignore that mummified remains—partial or otherwise—are also an exciting part of Yukon paleontology.
[40,000-year-old mummified black-footed ferret discovered by the McDougall family’s dog, Molly, at their placer gold mine on the Sixtymile River, from Ice Age Klondike, courtesy of the Government of Yukon.]
One of the more remarkable finds was a partially mummified horse, discovered by Lee Olynyk and Ron Toews in a gold mine.
[26,000-year-old mummified horse (Equus lambeii) foreleg showing preserved hair, hide and muscle tissue, recovered at Last Chance Creek, Yukon, from Ice Age Mammals of Yukon, courtesy of the Canadian Museum of Nature.]
[Image of mummified horse tail, courtesy of the Government of Yukon.]
Internal organs as well as a significant portion of the hide (with mane and hair!) were recovered. One can see this at the Yukon Beringia Interpretive Centre, the museum in the capital city of Whitehorse.
Also exciting, but from the neighboring Canadian Territory, was a discovery in the village of Tsiigehtchic. Dr. Zazula participated in uncovering this animal.
“[We excavated] a good portion of a carcass and a skeleton of a steppe bison, which turned out to be about 12,000 years old. There was still a bunch of hair and stomach and intestines and some of the limb bones were still articulated with muscle.”
He wrote about this in more depth with Dr. Beth Shapiro (image above) and several other colleagues in 2009. Not only remarkable for its level of preservation, this was also the first reported mammal soft tissue from the Pleistocene in “the glaciated regions of Northern Canada.”
[Large fossil steppe bison skull found Quartz Creek, from Ice Age Klondike, courtesy of the Government of Yukon. Not the same bison fossil mentioned above.]
Then in 2010, Derek Turner and Brent Ward found the “oldest reliably dated” Western camel fossil found in what was once Eastern Beringia. As mentioned in previous posts, Beringia was the area that covered most of Siberia, Alaska and Yukon when the land was connected in the Pleistocene.
Derek Turner, Brent Ward and Dr. Zazula explain, in their paper about this discovery, that North America was once home to possibly six different species of camel. (There appears to be some dispute about whether six distinctly separate species existed.) And, contrary to what one might expect, Camelops—the camel genus—originated in Central Mexico.
[Ice Age camel metatarsal (foot bone), courtesy of the Government of Yukon.]
For someone who has never participated in the excavation of either a mummified animal or fossils from permafrost, it was interesting to learn that there is a distinct smell when working with the muck.
[Placer gold mining monitor, Dominion Creek, courtesy of the Government of Yukon.]
“The only thing that’s kind of similar is the smell of a barnyard. But this is a barnyard from 30,000 years ago, and it’s from mammoths and horses and camels. All this rotten stuff that was [once] animals and plants that died a long, long time ago, frozen in the ground, and it’s now starting to thaw.”
The ever-growing research and discoveries from the Yukon paint a vivid picture of a by-gone era. It is, perhaps, the closest thing to a window into the Ice Age that we have.
When asked if there was anything that had not yet been found that he would be thrilled to find, Dr. Zazula didn’t hesitate: a woolly rhinoceros.
“We know that woolly rhinoceros are, so far, only found in Siberia,” he said, explaining why this would be so significant. “They extended all the way to the Bering Sea essentially, but they seem to never have crossed Beringia into North America. There is no fossil record of Ice Age rhinos here. But if they did [cross Beringia], that would be pretty amazing to find one of their fossils.”
Dinosaur enthusiasts, however, may be disappointed.
“In the Yukon, there’s almost no record of dinosaurs or Mesozoic fossils at all. I’ve been working with colleagues over the past handful of years, trying to find dinosaur deposits. But there’s no record of dinosaurs here except for a few handful of things. So, it’s not really [the place to be] if you’re interested in dinosaur paleontology. And that’s fine for me because then I don’t have to get involved in dinosaur work.”
“The Ice Age,” he continued, “is definitely what I’m interested in.”
[Paleontologist Grant Zazula with Ice Age horse skull, discovered this past summer, courtesy of the Government of Yukon.]
Dr. Zazula began grad school in Alberta studying anthropology. Initially, he wanted to become an archaeologist. His undergrad studies focused on Arctic people and research. A strong theme, he explained, centered on the first humans to cross the land bridge into what is now North America.
“I found myself becoming more interested in the environments that those first peoples in North America were encountering,” he mused. “Instead of just trying to study the people themselves, [I wanted to understand] them in more of a wider geographic or environmental context. So, I switched gears during my grad school days from anthropology into biological sciences.”
After doing paleoecological work in the Old Crow region of the Yukon, Dr. Zazula was invited to join a group of researchers working in the Klondike.
“We started doing fieldwork at these gold mines, and we kept on running into these strange balls of hay frozen in the frozen mud, in the Ice Age sediments. And we didn’t really know what they were at first.”
So he contacted Dick Harington—a well-known paleontologist within Canada for his decades of work with fossils and gold miners in the Yukon. Dr. Harington thought they might be Arctic ground squirrel nests, and in further conversation, explained that they had not yet been a topic of study. In other words, not much was known about them.
[Fossil nest of an Arctic ground squirrel, 30,000 years old, found at Quartz Creek in summer 2005, from Ice Age Klondike, courtesy of the Government of Yukon.]
“Over the first summer of fieldwork, I think I collected almost a hundred of these ground squirrel nests. And what was really cool about it is that the group that I was working with specialized in glacial stratigraphy [and] using volcanic ash beds to date sediments.
“Because they knew the age of these different volcanic ash layers that are found in the sediment, we could actually place these ground squirrel nests in different points in time in the past. We were able to develop sort of a time series of these Arctic ground squirrel nests.
“[Over] the next four years, I picked apart Arctic ground squirrel nests that [dated] between 20,000 and 80,000 years old or so.”
[Arctic ground squirrel nest, courtesy of the Government of Yukon.]
These nests are also known as “middens.” In his paper on the topic, Dr. Zazula and his colleagues describe these underground Ice Age homes. What these middens revealed, not just about these specific Ice Age animals, but about the Pleistocene environment at the time, is incredible.
Contained within these middens were ‘caches’ of food—seeds and plants from the area. These tiny plants give scientists a much better understanding of the climate and environment thousands of years ago.
[Arctic ground squirrel nest, courtesy of the Government of Yukon.]
[Arctic ground squirrel nest, cache highlighted by author, per the paper on this subject.]
“I think we’ve identified over 60 different plant species in them, and I wasn’t expecting that at all.”
In addition—and much to this author’s surprise–they found fossil insects, including beetles.
“Fossil Pleistocene beetle remains are actually quite common in sediments,” he said. “And they’re actually pretty useful for climatic reconstructions, because most beetles have a very narrow temperature or climatic envelope that they can live within.”
[Arctic ground squirrel nest, courtesy of the Government of Yukon. Can you find the squirrel skull?]
[Extant Arctic Ground Squirrel (Spermophilus parryii) hibernating in burrow, Fairbanks, Alaska; Getty Images]
In all of Dr. Zazula’s papers, one can see scientists from a variety of fields as co-authors or in the acknowledgements for their help with research. This was reiterated in our phone conversation: he is uniquely positioned as Yukon paleontologist to provide Ice Age material for a wide-range of study to a wide-range of fields.
“Especially with the Pleistocene,” he explained, “there are so many interconnected aspects of research. You need to have a geologist around. And then, in terms of putting the big picture together, you want to have someone that can reconstruct plant fossils. If you’re just doing it alone, you wouldn’t get much of the [big] picture anyway.
“So we’ve really kind of developed this way of doing things as a team.”
[Archaeologist Jana Morehouse, Paleontologist Grant Zazula and Geneticist Mathias Stiller, image courtesy of the Government of Yukon.]
“To me, it’s all so interconnected: the geology, the ecology and the mammals and then the archaeology. You might as well work together to try to accomplish goals, and that’s how we’ve done it. It’s been pretty successful.”
“And,” he added, “it’s a lot more fun that way anyway.”
[Geneticist Beth Shapiro with Ice Age horse jaw, image courtesy of the Government of Yukon.]
“Prior to the Yukon government establishing the paleontology program, all of the fossils that were being collected went back to Ottawa for the National collection and the National Museum. So most of the material that has ever been collected from the Yukon is actually not here. It’s in Ottawa.
“The Yukon government decided in the mid ‘90’s that they would like to establish its own program in Arctic archaeology and paleontology. Since that time, fossils collected here, stay here. And the position [of Yukon paleontologist] was created to oversee that.”
It’s a position he’s held for the past eight years, and one can hear his genuine enthusiasm for it in his voice.
“It’s a great job,” he stated. “Sometimes I’m shocked that I get paid to do this. It’s pretty exciting.”
Over the years, Dr. Zazula has been featured in some of the most prominent global media. Some of those include NPR, the CBC, the NY Times, and the National Post. This past summer, he was filmed with paleontologist Dick Mol from the Netherlands by a German documentary team. That documentary has been aired in Europe since this past December.
[Paleontologists Grant Zazula and Dick Mol, photographed by Florian Breier, the director of the German documentary; image courtesy of Dick Mol.]
Not everyone, regardless of their profession, is as comfortable with media or journalists.
“I think there are a lot of people that stay in labs and put their heads down and don’t really interact with the media, but I think it’s really important,” he said.
“[I]t’s one thing that’s never taught: how to conduct interviews or how to take your scientific work and present it or make it relevant to the public. And I think that’s a real problem, because if you are a practicing scientist after graduate school, you’re undoubtedly going to do research that attracts interest, and if you don’t have the ability to speak about it or to present it, you lose a lot of traction. In a lot of regards, science is kind of a big competition. It’s like a big science fair. If you don’t produce results and attract attention, you won’t continue to be funded. You can be an excellent scientist and sort of fade away if you don’t have the ability to attract people’s attention.
“I work for [the] government, where we’re publically funded by tax dollars. [F]or some people, [paleontology] might not seem very relevant for society. Still, I think it’s pretty important whenever we have something new to talk about, in terms of new results or new and interesting things, we should make sure it gets out to the public through media.
“Politicians are the people that decide if these programs continue to be funded. And if they see that there’s a lot of media interest and a lot of people learning because of it, then they’ll definitely keep funding these kinds of programs. And I’m grateful that they continue to do so.”
[Paleoecologist Rolf Mathewes from Simon Fraser University,courtesy of the Government of Yukon. Can you pick out the mammoth tooth?]
Explaining the reasons for his fascination with the Ice Age, Dr. Zazula said, “Dinosaur paleontology doesn’t really tell us much about the modern environment. If we’re interested in what we have today and how it’s changing because of, say, climate change, or environmental change, we’re not going to get much information about environmental processes by studying dinosaurs.
“The study of the Ice Age, [however], is how the modern world came to be.
“When you think of tens or hundreds of thousands of years ago, it may seem like a long time ago, [but] it’s just a geological instant. And in that short time period–in that geological instant–the changes that have happened to result in what we have here today are amazing!
“To think of giant elephants and lions running around North America: it’s such a different world. And yet so many aspects of that world can inform us of what we’re dealing with today.”
[Image of mammoth skull found by Hawk Mining along the Sixtymile River, courtesy of the Government of Yukon.]
This trilogy of posts on the Yukon–with all of the beautiful images and the fascinating information they contain–could not have been possible without the generosity of Dr. Grant Zazula. He is an adept and engaging speaker; the Yukon is incredibly lucky to have him at the helm of the paleontology program! Once again, and with great sincerity, a Mammuthus columbi-sized THANK YOU to him.
This trilogy would not have occurred without the great generosity and wonderful thoughtfulness of Dick Mol, who is a wonderful, wonderful person. With great sincerity, I wish him, too, a Mammuthus columbi-sized THANK YOU!
If you haven’t already checked out these publications by Grant Zazula, Duane Frose and Tyler Kuhn, please do! They are available online:
Other articles referenced:
- Arctic ground squirrels of the mammoth-steppe: paleoecology of Late Pleistocene middens (∼24 000–29 450 14C yr BP), Yukon Territory, Canada, Grant Zazula et al
- Last interglacial western camel (Camelops hesternus) from eastern Beringia, Grant Zazula et al
- A late Pleistocene steppe bison(Bison priscus) partial carcass from Tsiigehtchic, Northwest Territories, Canada, Grant Zazula et al
Yukon Paleontology Program: http://www.tc.gov.yk.ca/palaeontology.html
Yukon Beringia Interpretive Centre: http://www.beringia.com/index.html
Terra X – German Documentary: Mammuts – Stars der Eiszeit, http://www.zdf.de/terra-x/mammuts-ikonen-der-eiszeit-35507636.html