Whales form babysitting circle

Female sperm whales share care of offspring

source: New Scientist vol 202 no 2711, June 6 2009 p17

Female sperm whales share the care of their offspring, so that mothers can look for food. Shane Gero and team from Canada's Dalhousie University, Halifax, Nova Scotia, observed whales in the Sargasso and Caribbean seas. They found that Sargasso mothers took turns to care for calves, while Caribbean calves were left with female relatives, because there are fewer whales in the Caribbean, so fewer mothers to set up a babysitting circle. There are evolutionary advantages for the females concerned, since their calves, or relatives' calves are more protected. Large groups are also safer against attacks from predators.