Fake killer whales vs dolphins

False killer whales. They are relatives of the orca, six meters long and weighing over a ton. Traveling at 10 knots, the killers quickly close in on them. Something truly extraordinary happens. The dolphins turn as if to greet their pursuers. They seem to change their cause. Could it be that they're attempting to communicate? Scientists studying this annual encounter now think that individuals may recognize one another. Almost unbelievably, it seems that these different species appear to be old friends. Together, they're gathering as one unified army, up to a thousand strong.