Can Animals Be Altruistic?

How the flying V may be a rare example of “reciprocal altruism.’  

As with many birds, ibis fly in the V formation we’ve all seen pass above us. The V is a natural lesson in aerodynamics: Each trailing bird rides in the slipstream of the bird in front of it, stealing a bit of lift from the forward-position flyer. And as a new study reports, it may be a rare example of true “reciprocal altruism” in animals. Watch the video above to see how.