Sir David Attenborough is arguably the world’s favourite broadcaster, and this week he’s blowing out the candles on his 100th birthday cake. Inspired by his significant birthday, we decided to uncover the biology behind centenarians. What are Sir David’s secrets?

Speaking of ageing, we then find out about a little jellyfish that never gets old. Could it help us unlock immortality?

Next up, climb aboard as we chat with Dr Nadine Johnston, a marine ecologist who works on the iconic Sir David Attenborough research vessel, as she tells us about the tiny Antarctic animals that could lock up more carbon than the Amazon rainforest.

We then find out about improved landslide prediction in Nepal and how the world has changed in Sir David’s life.

All that, plus many more Unexpected Elements.

Presenter: Marnie Chesterton, with Chhavi Sachdev and Tristan Ahtone