Aphids and Ants

I have two "volunteer" sunflower plants this year. Oddly, they are spaced apart almost as though I planned it though God is the gardener in this case. I had one volunteer plant last year.

I'm not sure if it is all of the rain we have been getting or if these sprouted weeks earlier than last year's plant, but these are about 7 feet high currently. The flower part has started but of course not opened nor turned yellow yet.

Because these are right next to my den window, I can see them well. I noticed ants on the leaves, but the ants didn't seem to be wandering all over but clustered in small groups. Strange I thought. Now I am seeing more clumps so I did an internet search. Apparently, I must have aphids on the leaves, and the ants eat the honeydew excreted by the aphids. Since they don't want the aphids scattering all over, the ants "herd" them. Supposedly the aphids gain the benefit of being protected from predators by the ants. This relationship is considered mutually beneficial. So far the leaves don't look sickly and there are no ants on the upper leaves near the forming flower. Actually, one of the plants has only one leaf with ants, the other has 4-5. If the sunflower plant looks like it is being overrun by insects, I will have to figure out how to get rid of them. For now, the cowboy ants continue their herding and feasting.