Shut up about Joro Spiders, already

OK, enough with the spider freakout. I’ve been rolling my eyes so hard for the last few weeks that my ocular muscles are sprained. I’m talking about headlines like this:

Don’t journalists have a few other things they should be concerned about right now? This isn’t one of them. This is a great big nothingburger, unless you’re concerned about invasive species and the fate of their naturalized cousin spider, Trichonephila clavipes, which has been here in the southeast US for over a century, is about the same size as Trichonephila clavata (the Joro spider), and is just as harmless.

Oh, you’re not? Then shut the fuck up.

These are big spiders, but T. clavata is harmless. They’ll eat big bugs, but have no interest in you and can’t even bite through your skin. They’re also about the same size as Argiope, which we have in huge numbers up here in Minnesota, but T. clavata is only slightly more cold resistant than T. clavipes and has the potential to slightly extend their range. I only regret that I probably won’t find any way up here in the North.

But so what? Here’s where T. clavipes lives now (in blue), and where T. clavata has been found (in red). Don’t panic. They’re big, but they’re beautiful, and they’ll eat lots of grasshoppers and stinkbugs. Welcome them!

Read this for the True Facts.

Just so you know: last summer, we transplanted several Argiope from the edge of town to our natural garden in our backyard. They did well! I was a little concerned that we wouldn’t have enough food for them — I usually find them in open fields that are swarming with grasshoppers — but the female and male pair were thriving all through August, before they disappeared, as Argiope usually does when the weather cools. We’re hoping they managed to produce an egg sac or two to overwinter, which, with a little luck, will lead to clouds of little baby spiders ballooning over the neighborhood, and a repopulation of our garden. This is nothing to be feared! They’re gorgeous animals.

It’s unlikely that they’ll populate most of the yards in our neighborhood, unfortunately. Lawns are bad. They don’t produce enough big insect biomass to feed these animals.

My birthday is tomorrow

But I got a present from my wee little baby brother already. It was delivered yesterday, but then sat out on the icy cold back porch overnight, and Mary was a little concerned that it might have gotten damaged when she picked it up.

No worries.

It’s a cast iron spider, a species that does not mind sub-zero temperatures at all. I put it on a nice warm fluffy towel, though, just in case.

Sad, doomed little spider

Don’t worry, no photos of the pathetic creature here. Yesterday, I found one of my little friends in mid-molt — but there was a problem, and she had failed to extract her left legs, and so her limbs were immobilized and trapped in her old cuticle. I left her alone, hoping that today she’d have managed to complete the molt.

She didn’t.

I put her under the microscope, grabbed some watchmaker’s forceps, and delicately peeled away the stuff that had her legs bound. The operation was a success, in that all was removed without doing any further harm to the spider. But now her legs are deformed, and permanently, I think. They’re elongated, and locked together around the patella. She can’t move them. She drags herself around with her right legs, dragging the unmoving mass of the left with her.

I don’t think she’ll make it. This seems to be a common cause of mortality, general failures during molting. I’m suddenly grateful to have squishy stretchy skin that doesn’t need to be periodically replaced wholesale.

<shakes fist at sky> How could a benevolent deity allow such tragedies?

All right, all right, I guess there are legit reasons some people fear spiders

They are venomous, after all, some more than others.

The bite of the king baboon spider (which looks like a tarantula and lives primarily in Tanzania and Kenya) is not lethal, but it does produce a lot of pain in hapless victims. In this new effort to discover why, the researchers conducted a proteotranscriptomic analysis of the venom to identify possible peptides that they thought might be involved in producing pain. They identified one known as Pm1a (prior work has shown that it is typically involved in modulating dorsal root ganglion receptors in nerve cells.) They then synthesized the peptide to allow for NMR spectroscopy to ascertain its structure.

Next, they studied the impact of the peptide on mice by injecting a small amount into a toe. That allowed them to see that the peptide modulated ion channels and incited excitatory sodium currents. At the same time, it also reduced potassium currents that are typically involved in inhibiting excitatory currents. The end result was hyperexcitability in nerve cells, which, to the mouse, meant pain. To conclude their work, the researchers created a mathematical model of the peptide and its impact on nerve cells to further prove that it was the main driver of pain in victims of the spider’s bite.

The researchers also note that the hyperexcitability they saw in the mouse nerve cells very much resembled the type of hyperexcitability seen in people who experience chronic pain. They suggest that a better understanding of how spider venom can produce similar results could perhaps lead to a way to reduce pain in these patients.

I used to work down the hallway from a lab studying conotoxins. They’d collect the venom from cone snails, chemically separate its components, and then inject each fraction into a mouse to see what would happen. Sometimes nothing. Sometimes excruciating pain. Sometimes bleeding from the eyes. Sometimes they’d fall asleep. Sometimes they’d die instantly. It was fascinating stuff that yielded all kinds of interesting molecules with useful neurological effects. But you had to sometimes wonder, who was the monster? The organism that produced the venoms, who lived in a place these mice would never encounter, or the investigator who imported the toxins and afflicted them on hordes of mice, for the betterment of humankind?

Besides, the King Baboon spider has such a cute and adorable face. (No, no, no, arachnophobes. Don’t click through.)

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I miss the tetragnathids

I have been discovering that many people seem to have a weird perspective on spiders. They’re just animals, you know. They do the same stuff that squirrels or cats or lizards do: they eat, they drink, they court, and are entirely mundane in their behaviors. I’ve noticed, for instance, that one of the things that interested people was seeing that they drink! They have a heartbeat! I’m sure that even a moment’s thought would have made them figure out that of course they do…but we don’t usually think of spiders that way.

So here’s a story about a spider slurping up water and using it to rehydrate the dessicated bodies of their prey. Groovy. Spiders are clever enough to make instant bug soup.

One night in late December 2020, John Gould—a behavioral biologist at the University of Newcastle in Australia—was on Kooragang Island in southeastern Australia, surveying the area for a threatened frog species. Near an ephemeral pool, he spotted a long-jawed orb weaver spider (Tetragnatha) suspended in a web anchored in some vegetation. About two minutes later, Gould watched the arachnid suddenly “bungee” down to the pond’s surface, retrieve a large globule of water in its jaws, and race back up the silk line in a matter of seconds.

As soon as the spider ascended to its web with the liquid cargo, Gould knew he “had observed something really peculiar.”

He watched as the spider returned its jaws to a shriveled, partly drained insect it had been feeding on, droplet and all. The first-of-their-kind observations were published in the journal Ethology in January.

Just yesterday I was feeding my spiders and watched as one bungee-jumped down and scooped up a fly to haul back into its home cobweb. Clever girl. It was impressive how agile and adept it was, but that’s simply its nature.

Oh, also, tetragnathids are cool. They’re common, one of the more common spiders I see around here, but also diverse, with a lot of species I can’t distinguish. They make gorgeous orb webs, the classic kind with radials and spiral fibers, and they’re distinctive, with skinny, elongate bodies and huge jaws.

Now I’m pining for spring, when the tetragnathids will be back decorating the shrubbery in my yard. Until then, here’s a photo below the fold — arachnophobes, don’t click through!

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