Twigs with perfectly round holes in the ends often turn out to be the nests of Ceratina, pygmy carpenter bees. I found some nests in southern Greece, near Monemvasia, last spring. I opened one up and found a peculiar specimen with yellow antennae. When I looked at it more closely, I realized that the yellow appendages were fungal hyphae sticking out of the bee’s head. The rest of the fungus was growing inside the bee. The bee was still alive, but hardly moving.