Planet Earth Podcast highlights from 2012 - Planet Earth Podcast - 12.12.26

This week in the Planet Earth Podcast: a look at some of the highlights from 12 months of the Planet Earth Podcast, including: a hairy crab; earthquake monitoring in Turkey; air quality around London before the Olympics -- and early disease detection; Europe's oldest cave art; what the first creatures to walk on land looked like; and seabirds.