In this picture we see a calf sperm whale (called “Chopstick”) inserting the lower jaw for sucking milk from the breast of her mother (called “Can opener”). Mothers and calves form strong relations, even though the baby calves are raised with the help of “babysitters”, which often are sisters of the mother or younger sisters of the calf. The social structure of the sperm whale, which has the largest brain of any creature, is complex and fascinating.