Abbott's sphinx presents a fascinating example of polymorphism -- the occurrence of two or more very different forms within one species. The forms look like different species, but they're the same one, and even could have come from the same brood of eggs laid by one female. One of the forms is pictured here and is the one you are most likely to encounter; the other common one is gray. There's one more color form, a blue-white morph with a rounded orange "horn."

The caterpillars eat grape leaves. The adults, which look a like a piece of bark at rest, hover in front of flowers when they feed, making a faint buzzing sound and looking very much like a bumblebee.