Becky Ripley and Emily Knight get to grips with fatherhood in the animal kingdom by way of the largest land animal on earth, a fully grown bull elephant. Like the majority of mammals, male elephants aren't directly involved in raising the youngsters - that's left to the matriarchal herd composed of grandmothers, mothers and daughters. But you'd be wrong to think that means they don't have an influence. Via an extraordinary physiological phenomenon unique to elephants, known as 'musth', elephant bulls have a huge role in helping the teenage males navigate their tricky teenage years. And when it goes wrong, tragedy can strike. Back in the human world, dads play a major role in their children's upbringing. Human men are what's known as 'investing fathers', with powerful brain chemistry bonding them to their partners AND to their babies. The skills of fatherhood, which have evolved over millennia, are instinctive, biologically innate and hugely impressive, yet often get overshadowed by our culture's (perhaps understandable) focus on motherhood. Perhaps it's time for a rethink? Featuring conservationist Gus Van Dyk, and evolutionary anthropologist Dr Anna Machin.