Do whales need to rest? And if so, how do they sleep? In this week's episode I explore how sperm whales rest and how they use their social family structures to protect themselves and their female companions. I'll also talk about why male sperm whales don't travel with female sperm whales and why calves will stay very close to their mothers. We'll also explore why and how whale calves could drown... So much to explore about sperm whale logging!