Spreading aliens, Arctic experience, and Antarctica

Published: Sept. 27, 2011, 11 p.m.

This week in the Planet Earth Podcast, how hikers and walkers could be unwittingly changing the landscape by spreading alien species; what it's like to work as a marine biologist in the Arctic in temperatures of minus 40C; and exactly how stable is the West Antarctic Ice Sheet? Like this podcast? Please help us by supporting the Naked Scientists