There has been increasing public outrage at raw sewage discharges into our rivers and seas, but new research at Lake Windermere suggests that treated sewage is as much to blame. Wastewater experts Simon Evans and Ali Morse get into the nitty gritty of sewage treatment and why it might be causing so many problems.

Last week, the Sumatran orangutan Rakus made headlines when he was spotted by researchers treating a wound with a medicinal plant. A first for a wild animal. But he’s not the only animal to show self-medicating behaviour. Biologist and author of Wild Health, Cindy Engel, talks healing in the wild and what we can learn from the animals that do it.

And it’s that time of year again: the Eurovision Song Contest. In fact, this year marks the 50th Anniversary since ABBA won the 1974 contest with the iconic track Waterloo. Psychology and behavioural researcher Harry Witchel tells us what gives songs at Eurovision a winning edge and tries to predict a winner based on his criteria.

Presenter: Marnie Chesterton Producers: Hannah Robins, Ella Hubber, Sophie Ormiston Researcher: Caitlin Kennedy Editor: Martin Smith Production Co-ordinator: Jana Bennett-Holesworth