On page 39 of the paperback edition of the 25th anniversary publication of Edward Wilson's "Sociobiology," there is a picture of a hawk and some starlings. Below the hawk the starlings fly in tight formation. Above the hawk they fly in loose formation.
This is not altruism. It is the expected and predictable result of each starling's potential payoffs in two concurrent games, starling v starling and starling v hawk. It is sloppy science to use a term like altruism to describe such phenomenon, as it invites anthropomorphization and confusion when discussed with laypersons (and even some academics).