Unidentified ant on Peony
I sent this photo to bugguide.net to hopefully identify the species of ant but I haven't heard anything yet. This is the time of the year that the ants hang around on the developing peony buds, feeding on nectar that forms on the outside. Folk biology claims that ants are needed for the proper development of the flower, but this is not true. It's fairly likely (but hard to prove or disprove) that the ant and the plant are not even from the same continent, and that the observed relationship is a relatively new opportunism.