12/20/2020: Bristly beetle biceps

One of the best things about insects is finding little secrets about their anatomy, biology, or physiology. Today while photographing some yellow-bellied sun beetles I found something very funny. The dorsal and ventral surfaces of these beetles are very smooth… except for one area. The metasternum (higher level entomologists feel free to correct me on this!) and part of the middle femur are covered in bristly hairs. Considering this area has a swole, body-building appearance, the amusing question on my mind was this: why does this insect need hairy pecs? If anyone has an answer I’d love to hear it. I suspect it has something to do with burrowing, maybe routing substrate particles around the perhaps easier to mechanically jam body segments. Regardless, this discovery led to a few laughs and an equal amount of intrigue.

-Kyle