While we're at the beach...

The Venus flower basket is a sponge that lives deep in the ocean. It has a skeleton made of silica – hence its name "glass sponge". Here's a New York Times story about it.

Tiny shrimp swim in through its meshed boy, mate, and grow to a size where they can't get out, so they live their lives inside, together. That's why Venus is part of its name – goddess of Love (long-term).

I have one – about 12" long, very light and brittle. If I turn it upside down, I can hear the dried shrimp rattle inside.

Euplectella aspergillum

Drawings by Ernst Haeckel.