...and a capped giant resin bee nest in a carpenter bee tunnel. Giant resin bees
(only 'giant' compared to other bees in it's family) nest in the holes in wood,
especially those of other bees. It is notable in nesting in carpenter bee
tunnels where it rips out the carpenter bee eggs, young and pollen and
makes it its own nest. The resin is used to adjust the diameter of
it the absconded hole to it's desired size.
This carpenter bee riddled piece of wood used to be my mailbox post
Hymenoptera: Megachilidae: Megachile sculpturalis