Chambered Nautilus

I have to begin by saying that when I was in middle school I made a powerpoint presentation called Marvelous Mollusks, and I would truly do anything to find it. Unfortunately, I have the full text of the book I wrote when I was 12-13 (bad), but not Marvelous Mollusks. It was in a time of my life where I was really into adding power point animations, where you could like make a mollusk wiggle across the screen, and I have a strong sense that I overdid it. ANYWAY, I remember liking this guy, so here we go!

Are you kidding me with that face? (Photo is from California Academy of Sciences) Like horseshoe crabs, they are considered “living fossils,” because they’ve been around forever (California Academy of Sciences says ~500 million years, but I didn’t see that number anywhere else), and they haven’t done too much changing. They’re cephalopods, like octopuses and squids. Their bodies are really fascinating for a whole lot of reasons.

They’re famous for their mother-of-pearl shells, which they grow over the course of their lives. From California Academy of Sciences: “The nautilus literally builds itself a home as it grows, adding new internal chambers in a spiral pattern while always occupying the outermost one.” They make me think of hermit crabs, but instead of finding new shells, they build them, moving steadily outward. 

Even more interesting to me: they move around using a “hyponome”(NOAA fisheries calls it a sort of “siphon tube”), which lets them move around water and gas in their chambers, affecting their buoyancy. A blog entry from the National Marine Sanctuary Foundation says this is similar to how submarines work. They can also use the hyponome for a kind of “jet propulsion.” Here’s a video from the Monterey Bay Aquarium where you see one kinda floating around:

They live around 20 years, and they don’t reach maturity until they’re 10 or 15 (late bloomer alert), which is part of what makes them “particularly vulnerable to overfishing,” according to NOAA (they’re classified as threatened). They have limited eyesight but use “chemosensors” on their tentacles to smell food. They have over 90 tentacles. 

Here’s another video from NOAA fisheries using underwater cameras. There’s a moment in the video where a fish tries to bite one, at which point I screamed, “Hey!” They’re also interacting with each other; I can’t tell if they’re fighting or having sex (none of my business). 

https://videos.fisheries.noaa.gov/detail/videos/shellfish-other-invertebrates/video/3814028058001/nautilus-surveys-with-remote-underwater-cameras?autoStart=true

I know I’m talking a LOT, but there’s also a famous poem by Oliver Wendell Holmes Sr. that uses the nautilus’s outward expansion as a metaphor for the human soul. I found a 1938 journal article from American Literature by Nelson F. Adkins on JSTOR (why not) that points out that this use of an animal/ object in nature as a metaphor and tool for “moral instruction” reflects deist principles, which I thought was interesting, since we read The Age of Reason in my last class.