Yes, I know a lot of people ask this question. So let me say upfront I have read and I do understand the basic answers - it's easier to fly just above and to the side of the bird in front of you. And the lead bird only takes the lead temporarily. So I've got all that.

But what intrigues me is, how does a goose know to fly to the left of the bird in front if on the left side of the V, and to the right of the bird in front of it if it happens to be flying on the right side of the V?