Sponges are Confirmed as the Oldest Animal Phylum

To be honest, the taxonomic status of sponges has never worried me much, nor has it impinged on my daily life. Apparently though, the debate as to where sponges fit into the metaphorical ‘tree of life’ has finally been...

Valley of the Sponges Dive Site, St. Eustatius

Good morning, I’m finally getting around to actual dive photos I took on my last trip to the Caribbean, here’s a little window into a dive-site called “Valley of the Sponges”. The morning we did this dive a small boat came from shore over to our ship and picked me and two other Smithsonian friends up and off we went for a three hour, two tank dive. Because St. Eustatius is one big volcano we had to go almost two miles offshore to get to this dive-site, it’s for sure the furthest I have ever been from any given shore. I remember we were already soaked before we even got to the drop-site because of high winds, big waves and a tiny boat, good thing I had already put on my wetsuit.

Sponges, Sponges, Everywhere!

Sponges are great filter feeders If you do any diving anywhere, you will see sponges everywhere. Some of them are more colorful than corals, and some of them you can sit in. All sponges are water pumps and filters, which makes them useful in the sea and in our reefs. Sponges don’t move, they sit there, eat, and get fat. (Reminds me of one of my old girlfriends. She had the same complexion and personality as a sponge.) A typical sponge can pump 20,000 times its own volume in water through its cells in one day. All that water is also filtered by the sponge using “choanocytes,” which are just tiny, cone-shaped towers with sticky cells on them to catch food. Each tower has one flagellum, or hair-like thing

Rock Beauty Angelfish: a Finicky Feeder Best Left in the Sea

Rock Beauty Angelfish (Holacanthus tricolor)On one of my earliest dives down in the Florida Keys back in the 1990s, a gorgeous yellow and black angelfish caught my attention as I drifted over a section of reef. In my mind’s eye, I envision the angel hovering boldly above a large barrel sponge, but I can’t be sure whether that’s actually how it happened or just an idyllic memory. In any case, I was taken with its distinctive appearance and wondered whether it might make a good aquarium candidate. As anyone familiar with the fauna of the tropical western Atlantic has already guessed, the angel I saw back then was a rock beauty (Holacanthus tricolor)—a species that, unfortunately, tends to fare poorly in marine aquaria and is generally best left to advanced fishkeepers or, better yet, in the ocean where it can beguile other divers. I’ll get into why in just a moment.Physical traits H. tricolor is laterally compressed (flattened from side to side) and, in typical angel fashion, sports a sharp, backward curving spine on the gill cover (operculum). As alluded above, this species is yellow on the anterior portion of the body and on the caudal fin and black from behind the gills to the caudal peduncle (base of the tail). The margin of the anal fin, the edge of the operculum, and the opercular spine are orange.