From Bob Cory
I do not believe that a humpback whale that stops killer whales killing a seal is trying to save the seal's life (15 October, p 42). It is stopping the killer whales from getting an easy meal.
This has a direct benefit to the humpback: the killer whales go hungry and will be weaker if they intend to attack a humpback calf.
An indirect benefit may be to make a point: we are in charge and there are no easy meals round here – clear off.
Altrincham, Cheshire, UK
