Planet Earth online

This week: how woolly rhinos could bring insights into ancient climates, why breeding salmon is helping conservation and a device that can weigh the oceans.

This week in the Planet Earth Podcast: a look at ways to reduce the risk of urban flooding; identifying species and building biographies from tiny fragments of ancient bone; new species of fungi from the ocean.

This week in the Planet Earth Podcast: a look at the potential to generate up to 20 per cent of the UK's electricity from tidal energy; and why understanding the nuts and bolts of turtles' sex lives could help protect those most at risk.

This week in the Planet Earth Podcast: why textbook illustrations of our early ancestors may have to be re-drawn; and why underwater canyons contain a wealth of life, including some rather ugly-looking worms.

This week in the Planet Earth Podcast: decoding the ash tree's entire genetic sequence to produce a strain which is more resilient to ash dieback; the challenges of extracting biofuels from algae; and the latest news on Planet Earth Online.

This week in the Planet Earth Podcast: how a virus brought to the UK by insects poses a worrying threat to the country's great tit population; and which new technologies could affect global biodiversity in 2013.

This week in the Planet Earth Podcast: why understanding where plankton congregates can help us protect basking sharks and other marine creatures; how primates planning ahead tells us about our own intelligence; and how to predict dangerous climate tipping points.

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.

This week in the Planet Earth Podcast: how you can get involved in any one of the wealth of UK citizen science projects that have taken off recently, and why a little-known gas given off by many trees, ferns and mosses, could be contributing to global warming.

This week in the Planet Earth Podcast: an online tool to identify bats is helping to protect them, and it could make a scientist of us all. Also, an audio diary from a researcher from the National Centre for Atmospheric Science who's on the Isle of Arran in Scotland; and why there's more to ageing than telomeres.