Across our planet, natural archives preserve the biological footprints of species long gone, from woolly mammoths at the macro scale, through plants and seeds, to dormant bacteria and viruses at the micro end of the spectrum. And one environment that safeguards some of this material in the best condition of all is the cold - in other words, in ice. So, this week, we're going to look at what is sitting in nature's deep freeze... Like this podcast? Please help us by supporting the Naked Scientists