Recently, we had the opportunity to collect frozen bone remains directly from the permafrost in Canada, as part of our research on the evolution of flora and megafauna throughout the climate variations of the late Pleistocene (~10 to 100 thousand years ago). The two of us, along with ACAD director, Alan Cooper, travelled to the gold rush city of Dawson in the Yukon, where a few families are still mining for gold in the frozen soil. To reach the gold-rich layers, miners are using high-pressure water to accelerate the natural thawing of the permafrost, uncovering numerous fossil bones (our gold mine!) in the process. Most of these bones are from large mammals who were grazing in the steppes of the Berigian region a few millennia ago: mammoths, horses, and bison; though the burrows of ancient squirrels also survive, with fascinating plant material inside. Continue reading
by Alan Cooper
Having rigged the cave on the first day, I guess it was appropriate that I was the one to take the first descent into the chasm below. It’s caving lore something along the lines of the Captain going down with his ship – if you rigged it, you should be first to ‘test’ it out! Backing over the ledge and unlocking my brakebar, I descended about 3 m against a series of ledges – before dropping into open space. Looking around I could see several enormous nests, around a metre wide and made of big branches – eagles had obviously lived under the overhang of the cave entrance for many years, presumably until the grid was placed over the entrance. I’ve not seen eagle nests up close before and it was impressed how large they were. Pack rats were also nesting around these ledges – 100ft over space, and we saw several snake skeletons down in the cave attesting to the effective security systems surrounding their home! Continue reading
By Alan Cooper
Natural Trap Cave (NTC) has an impressive entrance pitch – which is concealed immediately below a large innocuous looking slab of limestone, in the middle of a gently sloping ridge overlooking Bighorn Lake on the border between Wyoming and Montana. As you walk across the slab you can see why anything with hooves, or running at speed, would have had no time to react when the cave entrance came into view – suddenly all the edges slope inwards steeply, and you’re looking straight down a hole, about 30ft wide, 100ft onto rocks at the bottom of a large chamber. As a result, over the last 100,000 years or so, a very large accumulation of skeletons has built up in the sediments below – standard herbivores such as bison, horse, and mountain sheep but also large numbers of carnivores including American Lion and cheetah-like cat (really a puma on steroids), many wolves, and even giant short-faced bears and mammoths. Continue reading
Alan Cooper answers your questions while in the stunning Natural Trap Cave, Wyoming. Find out how the team uncover, protect, and transport samples to our ancient DNA lab. Also, how this archaeological dig is part of Alan Cooper’s favourite ongoing project.