Spider deaths

The spiders I’ve been raising live to be approximately two years old in the lab. What typically happens is that they start showing signs of decline: they aren’t as responsive, they begin to hide in small silken nests, they fall into lassitude, and then one day they fall to the ground, dead. I worry that I’m doing something wrong, that the cages are too humid or not humid enough, that some disease is spreading through the colony, but I’ve tried different regimes of watering them, it makes no difference. It’s not surprising that very small animals are not evolved to endure. I tend to think “The light that burns twice as bright burns half as long – and you have burned so very, very brightly, Roy,” about my little friends.

They live longer than they do in the wild, at least. The past couple of summers I’ve kept my eye on a few spiders that take up residence on the outside walls of my house. They thrive for a month or two, and then one day they’re abruptly gone. There are waves of spider species that flourish over time: early in the summer, I start to see young Parasteatoda and Steatoda building cobwebs along the downspouts and under the windows; mid-summer I see them being replaced by the denser webs of grass spiders; around the time of the first frost, they’re all gone or in decline. We had a large, beautiful cat-faced spider lurking under the eaves of our house all last summer, and then in the fall we found her unmoving corpse. Every year in late summer those big yellow garden spiders take over the grasslands, building their zig-zagged orb webs and growing large enough to hog-tie grasshoppers, and then they die as winter arrives, leaving behind another generation that will overwinter in egg sacs. It’s a tough life, being a spider, especially when you live in a region with strong seasonal variation and severe climate.

And then I read about a trap-door spider in Australia that was documented as living for 43 years. I don’t consider most of Australia to have a gentle climate, but what they did have was constancy, so they could be adapted to a fairly uniform seasonal environment. She also didn’t have to cope with months of sub-zero temperatures, which are harsh on little poikilotherms, and that also wipe out the prey these predators have to consume. Even spiders in the Australian wheat belt are going to die, sometimes in even more horrific ways.

When she arrived at the clearing that day, she noticed that the twigs around the door had lost their meticulous spiral fan shape. They lay scattered in disarray.

Mason looked at the silk door, and saw a tiny hole in the center, as if something had pierced it.

She lifted the door and lowered an endoscope into the burrow, and confirmed what she already suspected. The spider was gone.

A parasitic wasp had likely broken through the seal, and laid its eggs in 16’s body.

“She was cut down in her prime,” Mason said. “It took a while to sink in, to be honest.”

On April 19, Mason, Main and Grant Wardell-Johnson co-published a paper in Pacific Conservation Biology, announcing the death of spider 16 at age 43.

She was the oldest spider known to have existed, Mason wrote, eclipsing the previous record set by a 28-year-old tarantula.

Ugh. Parasitic wasps. I think I’d rather freeze to death, or gently fade away in the decrepitude of old age.

Playing with my camera

Today’s spider time was a bit abbreviated, because my day is jam-packed with stuff scheduled on top of stuff, so I only had a brief moment in the lab. I decided to tinker a bit with a camera lens I’ve been neglecting, the Laowa 25mm f2.8 Ultra Macro 2.5-5.0x. This is a strange little lens with a lot of potential, but I have struggled with it before. It’s just so different from my other lenses, with different properties, and I think I’ll have to invest some serious effort to master. Today was not that effort. I shot a few quick photos before I had to refocus on today’s classes.

Spiders are the ideal models for macrophotography, because the ones I have are so calm and stable. This little lady was practically immobile for the entire half hour I spent playing with lights and backgrounds and moving in close for pictures.

One thing I discovered is that the Laowa is surprisingly good at collecting light. My first photos were at f/2.8, an exposure of 1/500, and they were all washed out. I kept reducing the exposure and closing off the aperture, and still got usable photos. So it’s got that going for it. On the other hand, the depth of focus is still pretty shallow and I had to stick the lens right in the spider’s face to get it in view, and one thing I like in a lens is a forgiving working distance. Fortunately, this spider was imperturbable.

Anyway, I played for a bit. The one on the left is shot at f/16, the other two at f/2.8. I’m not straining for light in any of them, which is nice. All are at 2.5x, I’ll have to try the 5x option next and see how that goes.

I have a mostly free day tomorrow! I’ll have to practice some more, and maybe do some comparisons with the Tokina Macro 100 F2.8 D, which is currently my favorite lens for field work. I don’t think the Laowa can replace it, but might make a good choice for the lab.

Now…on to classes and grading!

Sad day in the lab

With great sorrow, I must report the passing of a member of the lab family. This beautiful golden spider my wife caught in Colorado in January of 2020 is no more. She was the wrong species, Steatoda triangulosa, for the work I’m trying to do, but I kept her around because she was lovely and vivacious, with her golden color and zig-zag stripes, and she was always eager to kill anything I put in her cage. She’s so pretty her picture is my cell phone screen.

I’d noticed she was a bit lethargic lately, and wouldn’t respond to flies in her web. Yesterday, she was slumped low in her cobweb — they usually favor a high position — and was only feebly responsive to a gentle touch. Today, I found her corpse lying on the floor, legs curled inward.

It’d been a year and a quarter since she was caught as a fully grown adult, so she may have been a year and a half, possibly even just shy of two years old. That’s a long, long life for these little spiders.

Lab time, and a whatsis

Yesterday, Mary startled a jumping spider which had been hiding under a mysterious small object. That object was also attached to the wall of our house by strands of spider silk. Is it an egg sac? I put it under the microscope, and no, it is not.

It is something tiny, about 2mm long, and botanical. I know nothing of botany. It is not a spider thing, which is enough for me.

While I was in the lab anyway, I tended to the spiders, who are all doing fine. Here’s one just relaxing in a spider-like way.

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They’re like knitters, wrapping skeins, and bearing poisoned knitting needles

It was another morning in the lab, and as usual, I implemented my new feeding regimen. Previously, I was feeding the juveniles two flies, twice a week. I am now feeding them two flies, every day, and they are still avid and greedy and leaping right onto their prey. I feel guilty, like I must have been starving them. This also means more work for me in the future, but hey, it’s hardly working, and the customers at my restaurant are so appreciative.

I include a photo of one of the feeding spiders. There’s a lot of motion blur in the hind limbs because that’s what they use to draw out silk and wrap around the fly. She was whirring away pretty fiercely there!

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Tekporn, and a spider

Something for everyone! In the last spider zen thread, I showed off my collection of junk optics, and someone mentioned Tektronix oscilloscopes. I have those, too! Two of them!

These are relics of my old days, when I spent my day punching teeny-tiny electrodes into teeny-tiny neurons. I wasn’t a hard core electrophysiologist, I was mainly interested in delicately poking in without killing the cells so I could fill them up with interesting probes that glowed all kinds of garish colors. I brought them here with me with the idea of using them in neuroscience classes, but it turns out that you need all kinds of other infrastructure to do neurobiology of that sort right, which a small liberal arts college lacks (unless you’ve got a core of several faculty who were interested in building that infrastructure, which we didn’t have — I was alone.)

Anyway, these almost certainly don’t work anymore. They were old and finicky when I was using them, and they’ve been neglected for 20 years.

But who cares? Here’s a spider.

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The prodigal spider returns, and my cabinet of optical curiosities

I reported yesterday that the tiniest of my juvenile spiders had vanished, and I feared that she had escaped. I was wrong! She was still there, tucked away under a crossbar of the frame, being shy and quiet. Either that, or she had just taken off for a day to fight crime. She was famished and immediately chowed down on a fly this morning, so that is a possibility.

I also mentioned that in my ongoing lab clean-up efforts, I had unearthed another assortment of microscopical oddments that I tucked away in my cabinet dedicated to antique optics, and threatened to show you some of it. I now make good on that threat.

My predecessors at this university in cell biology, Drs. Abbott and Gooch, collected a few gadgets and were clearly imaging people. Some of it was just lying around in boxes, and when I find it, I fish it out and toss it onto a shelf. It’s really just junk at this point, and I have no use for any of it, but once upon a time these things cost a lot of money and I have a fondness for old technology, so as long as I’ve got the space, I’ll hang onto it.

Here’s the whole cabinet. It’s just a hodge-podge, not organized at all.

Look at this — a real treasure. That’s a Konica (now Konica-Minolta) Hexanon camera lens! Those, once upon a time, were high-end optics — now though, they don’t fit any camera I’ve got, and you can’t even get adapters to make them work with DSLRs, since the focal length is too short. I’ve thought a few times about collecting old lenses to play with photographically, when I get rich, but this one…nah, sadly, not something I could use, unless I were to also collect old camera bodies. Nope.

There are also a few cheap video lenses in view, and I’ve got a few CCTV cameras that seem to work, if ever I wanted to image stuff with RS-170 again. Ooh, 525 lines of fuzzy resolution. Also lenses from Cosmicar (a division of Pentax) and Computar (which is still around, making lenses), and several C-mount adapters for various microscopes.

I have a couple of Zeiss lamp housings and this tube for a fluorescence microscope. Someone was doing some nifty stuff in the 1970s, I suspect. There are also a couple of massive illuminator bases with interesting clamps — part of an optical bench setup?

These were some other curiosities very neatly packaged in solid boxes with faded velvet padding: something called an optibeam, a name I associate with antennas, but this has a couple of lenses, so I have no idea what it’s for. There’s also a massive syringe of metal and glass, very impressive, I might have to use it to terrify the grandchildren.

Not shown: I also have some mystery boxes of my own, with DECtape reels and Zip drives, which were all the rage in the 1990s. They seem quaint now — 100mb on a clunky plastic drive when I’m carrying around a terabyte in my pocket, on little thumbnail sized chips? Nah, they’re about as obsolete as all the junk on my shelf.

If you see something in those photos that get you excited, though, I can probably make arrangements with the university bureaucracy to ship them out. Otherwise, I predict that my successor someday will just sweep them all into a box and send them off to a landfill.