Why is it that so many long distance runners are from Kenya? Is it genetics that leads to the high performance we can expect to see in the London Olympics? Or maybe the stamina of the world's best athletes is above all about their mental attitude, the ability to deliver excellence, no matter what?
Just some of the aspects of endurance we are exploring on the Forum this week with high-performance anthropologist Rasmus Ankersen. Also on the programme, award winning photographer Rachel Sussman takes us hunting for the longest living organisms on Earth. And endurance that dwarfs anything found on our planet: the mind boggling staying power of the stars in the sky. The UK's Public Astronomer Marek Kukula is our cosmic guide.
Illustration by Emily Kasriel: the race to endure for sports people, stars and other forms of life.