Wednesday, February 24, 2010

Yukon Caribou genetics research

CKRW 8:00 A.M. NEWS                                            WEDNESDAY, FEBRUARY 24, 2010


3.                     DNA recovered from ancient caribou bones in southern Yukon has revealed a possible link between several small caribou herds and a massive volcanic eruption that blanketed much of the territory in a thick layer of ash over 1,000 years ago. The study was conducted by an international team of scientists from the US, the UK and Canada who have been studying the history of the fragile species. Yukon paleontologist Dr. Grant Zazula says this latest study shows the massive impacts and eruption of a huge volcano in southern Alaska had on wildlife in Yukon almost 1,000 years ago.

(Zazula) “It’s something called the White River ash and if you drive on the highway from here to Carmacks or even if you just scuff under the soil you see this white power and it’s from this volcanic event that took place at a mountain called Mount Bonachurchill(sp). It’s by the Yukon/Alaska border and it’s probably one of the most significant volcanic events of the last 10,000 years, massive volcanic eruption so basically the entire Yukon or at least the southern half of the Yukon was blanketed by thick volcanic ash and volcanic ash is basically pulverized glass so the disruption to the environment must have been just amazing. It seems like what happens is the caribou that were living in that area prior to this volcanic ash eruption were probably either wiped out completely or displaced somehow. They had to migrate to some other area because their habitat was completely destroyed by this volcano.”

A Whitehorse native and Simon Fraser University graduate Tyler Kuhn worked on this study by taking bits of ancient DNA from caribou bones found in 6,000 year old snow patches. Zazula talked with CKRW about the unique Yukon climate and how those snow patches preserve bones and help researchers peak into the past.

(Zazula) “What’s so remarkable about these sites is because when the bones are deposited on these snow patches they’re basically frozen since the time the animal dies so when the bone is say deposited 8,000 years ago, it remains frozen so all the proteins and DNA preserved within the bone is perfectly preserved so you can look at the evolution of these animals and look at how the populations have changed through time and there’s not too many places in the world where you can find 8,000 year old caribou DNA preserved in bone. The Yukon is an amazing place for this kind of research and we’re really glad to be a part of it here.”

Findings from the report compared ancient DNA with DNA from caribou living nearby today and found that bones older than 1,000 years in Whitehorse did not match. The study more than a decade in the making also indicates today’s modern caribou turned out not to be related to the herds to the northeast or west and represent new arrivals possibly from further south.

(Zazula) “There’s been a collaboration between the Yukon government and a number of the Yukon first nations and scientists from universities have been working on this project for I think it’s almost 12 years now, and developing the history of hunting in the alpine zones, the changes of technology between different types of bow and arrows and different types of throwing spears and also looking at how these caribou populations have changed so this sort of research has been ongoing for over 10 years now and this is just the newest report to come from it and it’s basically the first major report on the genetics from the caribou populations that are preserved in the ice.” The research is the first to identify a possible link between changes in local wildlife and the volcanic eruption in a document that was released on line yesterday.
 
CBC 7:30 A.M. NEWS                                                   WEDNESDAY, FEBRUARY 24, 2010 

                    A Whitehorse researcher is finding some clues about modern day caribou in some 6,000 year old DNA. Tyler Kuhn a graduate student at Simon Fraser University. He worked with an international team trying to compare ancient DNA samples from frozen caribou to modern day species. One of the things they found was that the Southern Lakes caribou herd seems to have diverged genetically from other Yukon caribou about 1,000 years ago. That’s right around the time of a gigantic volcanic eruption. It covered much of the Southern Lakes area in a layer of ash called the White River ash. Coon says that impacted the caribou there. (Coon) “We think what actually happened is that after this volcanic eruption the caribou that were in this area actually got pushed away from the area or they disappeared locally and allowed a different group or herd of caribou to come in.” Coon says they’re still lots of work to be done but he’s happy to be working on the problems and says finding out what happened in the past may provide clues to protecting caribou in the future.