THE ALL-CANADIAN BEAVER
Canada’s national animal has officially been the beaver since a royal proclamation in 1975 though the toothy rodent first appeared on a coat of arms here in 1633. It has been an essential part of Canada’s history since well before Canada existed. For the First Nations, beavers were a source of fur and food as well as an important trade good. For Europeans who came to North America, the animal’s fur was the primary source of wealth. The beaver, historians will tell you, is why Canada exists.
A recent project by the Centre for Applied Genomics at the Hospital for Sick Children in Toronto has implications for understanding the beaver’s rich Canadian history and its conservation future — and for helping human health. While the centre and its director, Stephen Scherer, are more known for their work on human genomics, the beaver was the first of a new series of projects to sequence the genes of non-human Canadians. “To know about its genome allows us to better understand how it all came about: its history, how it relates to its environment,” Scherer said. “The genome is a starting point.”
They started with the beaver for Canada’s 150th birthday. Although the move was motivated by the beaver’s cultural importance, Scherer said in an email interview with Canadian Wildlife, it also has practical applications for his centre.
Human geneticists regularly compare human genomes with animal ones, he said. In fact, one of the first people to use the beaver’s newly sequenced genome was a hospital biochemist who works on heart disease. “He wanted to see how the beaver's elastin gene, which makes the protein integrally involved in how the heart beats, compares to that in human developing hearts,” Scherer said. “Most of our efforts are on human genomics. That’s what pays the rent. But it actually stimulates us intellectually to look beyond what we’re doing.”
To get genetic material for their study, the team turned to Ward the beaver, who lives at the Toronto Zoo. Collaborating with the Royal Ontario Museum in Toronto and the zoo, they got some of Ward’s genetic material and worked to sequence it. Unlike much of their work with specific parts of the human genome, which has already been sequenced, they had to start from scratch.
All the while, the team was working against the clock: a different team in Oregon was working on the beaver’s genome as well. The Canadian researchers wanted Canada’s national symbol to be sequenced here. They won, publishing their peer-reviewed results on January 13.
Although 20 subspecies of beaver once existed across North America, says the study’s lead author, Si Lok, only Castor canadensis canadensis, the beaver associated with Canada’s Hudson Bay region, remains. That’s because beavers were hunted to extinction in many places by trappers, he says. “A lot of the beaver populations living now are reconstructed by introduced (Canadian) beavers,” Lok said. “There are no American beavers. There are only Canadian beavers living in the United States.”a
JUST IN TIME FOR THIS COUNTRY’S 150TH ANNIVERSARY, RESEARCHERS AT A TORONTO HOSPITAL HAVE SEQUENCED THE GENOME OF OUR VERY OWN CASTOR CANADENSIS CANADENSIS.