They come from a group from the University of Alberta, who were exploring an area around the Teardrop Glacier, high in the Canadian Arctic. The glaciers in the region have been receding at rates that have sharply accelerated since 2004, at about 3-4m per year. That is exposing land that has not seen light of day since the so-called Little Ice Age, a widespread climatic cooling that ran roughly from AD 1550 to AD 1850. "We ended up walking along the edge of the glacier margin and we saw these huge populations coming out from underneath the glacier that seemed...