I was at the New York Aquarium this weekend, and a marine gastropod of some sort treated me to this little show. I’m linking to the video because embedding doesn’t seem to work. Hrm.
That bit of anatomy, um, undulating is the radula, a toothy tonguish apparatus that mollusks use to eat. I hope there was some good grazing on the side of the tank there.
The cool thing about the radula is it’s unique to mollusks. When a fossil of Kimberella, an Ediacaran organism (that’s Precambrian!) showed evidence of a radula in associated scratch marks, that made folks change their mind about whether it was a jellyfish as originally supposed. It’s not definitely classified as a mollusk, but it is at least a bilaterian.
(photo credit: Aleksey Nagovitsyn)
You can’t see evidence of a radula in this photo (as far as I know), but I love a good fossil.
The uncool thing about this video is that I don’t know what species that little dude, lady, or dudelady is. This is a frustration of mine at aquariums. Unless the purpose of the tank is to showcase a particular invertebrate, they tend to omit any information at all about them. There is usually signage IDing all the fish (I call vertebrate chauvinism!). While I understand that most of the people visiting aren’t particularly interested in the particulars of species names, and also that a litany of latinate names can be offputting and counterproductive as a means of getting people interested in science, I wish there was some way to get that info if desired– a panel one had to lift, a link to a website, something.
The best story I saw in the news lately about fossil markings being evidence of other interesting things is no doubt the fossil evidence of zombie ants because they left telltale toothmark death grips on fossilized plant leaves. Too terrifying for words.