Right beneath the lavender ribbon I tied on the azalea to tell the painters not to trample it this spring, I saw this Eastern black swallowtail caterpillar, and I knew he was getting ready to pupate. His body language is completely different from when they’re pigging out on parsley or, in his case, rue. He’s very straight and compact and — not eating.  For a caterpillar, “not eating” is not an option. 

Here’s what they look like while they’re eating:

Relaxed, curvy, stretched out, shoveling it in. That’s their job at the larval stage.  

In the picture at top of this post, he’s on an azalea twig – not a host plant, and too woody to eat – and perfectly straight, and still.