I never really understood tinsel. In theory it seemed like a good idea: somewhere between subtle and gaudy, a simple shiny decoration for your Christmas tree. In reality, it is a mess of clingy strips of plastic that never really deliver on its ornamental promise. As I get older it only seems that much more curious to throw plastic on something as beautiful and natural as a tree. (Of course, I suppose it’s less curious and more grotesque when one thinks of “Tinseltown” and the plastic thrown on and into human bodies.)
Some caterpillars, including the Milkweed Tussock caterpillar pictured above, are adorned with setae: thin hair-like structures or, as you might say, “anti-tinsel.” They can be showy, but that showiness doesn’t invite one into a mess, it more typically keeps one out of it. If people handle such-adorned caterpillars, the tips of the setae can dislodge and stick in the skin ultimately causing irritations or allergic reactions. They also can deter hungry, would-be predators (the softer, wormier version of steel brush bristles). These structures enhance their owners in a purposeful and artful way; they stop us and make us look, and then, hopefully, see.
So maybe these well-decorated caterpillars are like short, crawling segments of stinging garland, which is an altogether superior form of ornamentation. Just do not put them on the holiday tree (especially if they feed on milkweed)!