Dr Chris Smith and the Naked Scientist team present the latest science news, analysis and breakthroughs, In this week's episode...scientists unveil prehistoric cases of Down’s syndrome, but how did they find them? How whales really produce whale songs and the famous fake fossil that foxed palaeontologists for the best part of a century. Plus we’re taking a look at the so called “Forever Chemicals”…what are they? And how they might be damaging for us and the environment. Get the podcast from the BBC Sounds app.