Why do we find Bottoms Attractive?

Why is Jupiter round and how does it hold onto its gas, how does skin thickness vary around the body, why does milk soothe the effects of chilli, how do brain sizes vary amongst animals, what makes a person blush, why don't we deafen ourselves when we shout and what makes bottoms attractive? Join Dr Chris as he pits his wits against this week's crop of questions... Like this podcast? Please help us by supporting the Naked Scientists