French Artist Gives Caddisfly Larvae Gold & Jewels to Build Their Protective Cases

I say the division of labor is limited by the extent of the market:

Generally, the protective silk cases the caddisfly larvae build are decorated with gravel, sand, snail shells, twigs or other common debris but French artist Hubert Duprat gave them shinier materials. He introduced beads, pearls, turquoise, and 18-karat gold pieces into their environment and let them construct tiny gilded sculptures. Duprat has been collaborating with the larvae since the 1980s.

One link is here, via the excellent Mark Thorson, with further images and video, another link is here, more pictures and an interview with the artist.