Even though I have lived in California for more than a decade, I have never visited Mexico until a week ago. Countless gift shops aimed at tourists lined the streets of Ensenada, but one peculiar item caught my eye: Mexican jumping beans. I had to find out for myself what animal inside caused these beans to jump (although I later found out that these are not beans at all but seed pods)! Yes, I will shamefully admit that this was my only purchase on my first trip to Mexico. And yes, I was so eager to find out what was inside that I spent a good part of one evening in my hotel room Foldscoping the inhabitants of these jumping beans.
It turns out that in each “bean” is a moth larva (Cydia deshaisiana), nestled in snugly. These larvae, when exposed to heat (such as the warmth of a hand or direct sunlight), begin to spasm in an attempt to roll their home toward a cooler location. To take a closer look, I opened a bean up and removed it from its home.