Black Swallowtail

Is it my imagination, or that blogging makes me more attentive, or are there actually a lot more butterflies about this year? I'm thinking the latter. The cone flowers in the back have been loaded with multiple tiger swallowtails, monarchs, red admirals, and these guys, black swallowtails (Papilio polyxenes), essentially non-stop, dawn to dusk. It wasn't until I examined the image that this was actually a black swallowtail and not a spicebush swallowtail, as I had originally thought when observing them. But the two are very similar. They both mimic the pipevine swallowtail, whose larvae store aristolochic acid from their host plants and pass it along to the adult stage, making them toxic or at least bad tasting to predators. The mimics don't share this toxicity, but trick predators into avoiding them by their close resemblance to the pipevine swallowtail. Click on the image below to view it at full resolution, a quite different and closeup view of these beautiful insects.