Today, mathematician and Hero of Intellectual Freedom, UC Davis’s Abby Thompson has more lovely intertidal pictures from California. Her captions and IDs are indented, and you can enlarge the photos by clicking on them.
The Northern California tidepools are filling with kelp, and creatures are hiding away under it. Here are some photos while there’s still a bit of summer left. These are from July, except for the pelicans (August 1). Thanks as usual to experts on inaturalist for some of the IDs.
Tegula funebralis (black tegula): I love these tracks on the sand at low tide; it looks as though the snails are trying to tell us something:
Closeup of the barnacle-encrusted snail from the first photo:
Hesperocyparis macrocarpa (Monterey Cypress). The trunks get stroked by many hands as people pass them on their way down to the beach:
Pelecanus occidentalis (brown pelican): There must have been a large shoal of fish near shore; the pelicans (it seemed like hundreds of them) were going nuts. Their lethal dives, with those incredible beaks, makes their relation to dinosaurs look very convincing. The Point Reyes peninsula is in the background:
Family Ammotheidae (Pycnogonid-sea spider): The lumpy white spots on the legs are eggs (what a place to carry them!), which I believe makes this a female. The males carry the eggs after they are fertilized:
Tenellia lagunae (nudibranch):
The next few photos are through a microscope. I have an ancient Leitz Wetzlar dissecting scope, with an old iphone precariously clamped over one eyepiece. There must be a better way, but I haven’t figured it out yet.
Diatoms: Genus Isthmia; Lou Jost’s beautiful post on WEIT on the Challenger Expedition and the diatoms they found was inspiring. It’s disconcerting, as a non-biologist, to look through a microscope at a fluffy, frothy bit of seaweed (the reddish stuff) and see, scattered all through it, these incredibly regular geometric shapes:
Diatoms closeup:
Neosabellaria cementarium ((tiny) polychaete worm):
Phylum Foraminifera: This was a surprise to me, partly because I had never heard of foraminifera, but mostly because it turns out they’re single-celled organisms (like diatoms), so that’s one cell you’re seeing. Google AI says this about the difference between diatoms and foraminifera: “Diatoms are photosynthetic algae with silica cell walls, while foraminifera are amoeboid protists with calcium carbonate or agglutinated shells.”
There are many more elaborate/complex ones than this one (there’s one that looks a lot like a loaf of challah, for example). It’s worth googling “foraminifera” and “Ernst Haeckel” to see some amazing illustrations. The Challenger Expedition discussed by Lou Jost also collected and documented foraminifera. According to Wikipedia, the first picture of one was by “…Robert Hooke in his 1665 book Micrographia”. This book (available through WikiSource online) has charming sections like: “Of the Teeth of a Snail”, and “Of blue Mould, and of the first Principles of Vegetation arising from Putrefaction”. The possible foraminifera appears as figure X in Schema 5. He says (in Observation XI) “I view’d it every way with a better Microscope and found it on both sides, and edge-ways, to resemble the Shell of a small Water-Snail with a flat spiral Shell:” Imagine being one of the first to be able to peer into this world!
The camera for the first six pictures in an Olympus TG-7.
Thanks Abby. How old does a snail have to be to be barnacle encrusted, I wonder?
Very nice! Those are better microscope pictures than what I can get. There are lots of adapters for attaching a cell phone to a microscope, but are any any good? My method is just to hold by hand, and ‘spray and pray’.
Thanks! I bought this clamp: Celestron – NexYZ – Universal Smartphone Adapter – and, after considerable fiddling, it works ok. I have to use an older iPhone- the camera on the new ones is too smart, and it keeps switching lenses on its own.
This series is almost an unintended counter to AI imagery … that with plain modern technology, it is possible through plain effort, to find insight that seems other-worldly …
right in front of our eyes
… like the one correct chess move out of the many wrong moves…
Ordinary vs. extraordinary
Is the distinction I was illustrating.
Thanks for these photos. It’s fine to be variety and and vigor of the contributors. Thinking about biology is one approach to being absorbed in complexity.
I liked this: “It’s disconcerting, as a non-biologist, to look through a microscope at a fluffy, frothy bit of seaweed (the reddish stuff) and see, scattered all through it, these incredibly regular geometric shapes” — and then, I think, after a bit, one goes to expect to find this sort of thing, at nearly every level.
These are magical, especially the microscope photos. And what do you think the scribbling snail is trying to tell us? A warning about sea level rise??
Thank you for allowing us to see into this other world of diatoms and foraminifera.
It’s gorgeous.
Yes. Forams are hugely important organisms used in biostratigraphy—the study of the temporal and geographical relations among marine sedimentary rocks. Their calcium carbonate shells (called “tests”) are super abundant in both nearshore and deep-water marine sediments.
And, Tegula funebralis brings back memories. It was one of the experimental animals I used in my doctoral dissertation. Beautiful and interesting little snails, members of an ancient clade that goes back to the late Cambrian (the clade, not this particular genus). I didn’t know you could eat them but, of course. Why not? Eating them would be a lot of work since they are so small.
Thanks all for the kind comments!
Thanks for finding more diatoms for WEIT! They are amazing and they are everywhere.
Fantastic photos, Abby! Thanks for sharing these.
Thank you! I always enjoy your posts and your insightful comments.