We need bigger spiders in Minnesota

Poking around in the weeds as we do every summer, looking for spiders, one thing we turn up a lot are frogs. Big frogs. They like to nestle in some nice shady leaves during the day, and we occasionally part some leafy foliage to find a frog looking back at us, as if wondering how dare we intrude on his home. I’ve often thought they need a good predator to teach them a lesson.

Like a clever huntsman spider.

Retreat and predation event near retreat of Damastes sp. (a) Spider specimen of Damastes sp. (THC140, adult female), the prosoma and opisthosoma are approximately 1.5 cm in length (smallest square = 0.1 cm)—Observation 1; (b) Damastes sp. feeding on Heterixalus andrakata (frog) inside of the retreat, built of leaves of Tambourissa sp.—Observation 1, (c) Predation event where Damastes sp. captured Heterixalus andrakata near the retreat—Observation 1; (d) Damastes sp. hiding in the retreat, built of leaves of Cedrela odorata—Observation 4

These cunning ambushers from Madagascar use silk to stitch together a few leaves, making a nice shady refuge that might appeal to a frog looking for respite from the daytime heat. The frog snuggles in, not noticing the large-fanged venomous arthropod lurking in the back, and then snicker-snack, he’s a juicy piece of meat being sucked dry by Damastes.

I don’t know about you, but if I poked my face into a local bush and saw a big glorious spider instead of a fat frog, I’d be delighted. It’s not likely, though, since our harsh winters tend to kill off most of the spiders, giving them only a short growing and breeding season.

Maybe this would be a bright prospect from global warming? Do you think Republicans would be even more resistant to the idea of good legislation if they thought climate change would create a better environment for big hairy blood-suckers? They do have some things in common.

Spider skeleton

It must be convenient to be a spider at Halloween. To decorate, you just rummage through your closet and pull out an old molt — instant skeleton!

The good news, too, is that my latest generation of spiders are growing up, and starting to molt. Here’s a shed spider cuticle I found today.

They shed by popping open the top of their head, which you can see at the top left, and then back out, pulling their legs up out of the old limbs. I keep hoping to catch them in the act, but I think they do it in the middle of the night, to minimize the danger while defenseless.

I put a picture of her post-molt down below.

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Have you ever seen a spider’s heart beat?

Now you can! I saw that I can easily visualize the hearts beating in my baby spiders.

It made me think of those Pro-Life Across America billboards that show a picture of a cute baby and declare “My heart began to beat at 18 days!”, as if that was a significant event. So I take it anti-choicers who see this video will forever after be kind to spiders?

Big boy gettin’ swole

Today was a big spider maintenance day. I’ve got three lines of spiders I’m raising — R (from a spider collected at Runestone park), H (from the local Horticulture garden), and M (from the Myers garage) which I’m trying to bring to maturity, so they’re getting lots of food and care, which I want to start inbreeding and generate 3 lines of related spiders so I can start assessing their variation…and then start cross-breeding. It’s going to take a while.

Anyway, down below the fold is one that’s definitely male and might be ready for mating after the next molt. His palps look painfully swole.

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Lunchtime in the lab

Not for me, of course — people don’t eat food in the lab — but for the adorable baby spiders, who got some delicious live flies and immediately wrapped them up and sucked their brains out. I’ve got two photos of two different spiders that adopted remarkably similar feeding behaviors, biting their prey in the head and slurping up their juices.

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A mundane cleaning day

Did you know classes start in 2½ weeks? It’s astounding; Time is fleeting; Madness takes its toll…but rather than doing the time warp, unfortunately, I spent several hours doing basic custodial work in the lab. First, a colleague and I scrubbed up the cell biology lab, shuffling computers into storage and putting away glassware, because that space will be used for a different course Spring semester. It’s tidy! And shiny!

Then I went into my lab, which is cluttered and grimy, and I need to make a few trips to a dumpster and polish up a whole lot of stuff — the sink is piled high with empty spider vials that need washing, for one thing. Today I set aside all the menial labor, though, and instead dismantled my microscope and cleaned up all the optics. That was fun! I may do it again tomorrow!

The filth wasn’t as bad as I feared, fortunately. One glass surface had accumulated a bit of dust and grime, and was fairly easy to wipe clean. I did have to take apart a few subassemblies, but thankfully, good German engineering made it easy.

I had to test it out with a few photos, but whereas the engineering was cooperative, the spiders were not. The entire interior of their condo cube was an intricate network of spider webs everywhere, so opening up the cube always tore their webs, making the kids frantic and excited, so they were mostly unwilling to sit still for their portrait.

I put a sample spider photo below the fold, and you’ll see what I mean — it’s all criss-crossed with silk, and I played a few lighting games to make it visible. Also note that the image is much, much better than the last spider photo I posted here.

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I haven’t cleaned the trinoc since when?

This morning I resolved to figure out what was going on with my muddy images from microscope. The first step was a general cleaning, and I discovered a real horror. Here’s the trinoc head for my Wild M3C:

See that tube on the right, for the camera? I looked down it. GAAAAAA. Dust and dirt and I swear, cobwebs all over. It’s a 30 year old microscope, and we’ve had microscope technicians come through every couple of years to do general maintenance on all the teaching scopes, but that tube may not have been cleaned ever in all that time. There’s a very important mirror down at the bottom of that L-shaped widget, and I think the only way I can get at it properly is to dismantle the whole device — there are a couple of tiny metric hex bolts holding it all together, and I guess I’m going to have to take it apart and try not to break everything.

Anyway, I did push the dirt around a little with a microfiber cloth, and it’s slightly better, but I think it’s filmed over with something that is fouling the image. I took a test photo of this little guy, and it’s an improvement, but still far from perfect. The image through the eyepieces is beautifully crisp, so I’m definitely blaming the problem on that little mirror and decades of neglect.

‘Ware spider below the fold!

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School portrait day

The spiders had to line up for their pictures today. I had a fixed routine, like a real portrait photographer.

  1. Fetch a spider condo cube from the incubator.
  2. Take a low power photo of the label, so I have a record of who is who on the camera ‘roll’.
  3. Carefully remove the lid to avoid startling the spider. They’ve already built elaborate cobwebs criss-crossing the chamber, so that didn’t always work. I wanted them still so I could get a focus series.
  4. Shoot a bunch of pictures.
  5. Spritz them with an atomizer of distilled water to gently convince them to change position. It also waters them — what was neat was watching them drink. A drop of water was roughly softball sized relative to the spider — they’d gather a droplet, bring it to their mandibles, and then you could see the droplet rapidly shrink as they slurped it down.
  6. Take another set of pictures.
  7. Flick a fly or two into the container as a reward.
  8. Put the condo back in the incubator.

It was a fun process, but I’m a little unhappy with the quality of the images — they’re not coming out very crisp. It may require some tweaking to compensate for the microscope adapter. Everything looks great through the eyepieces, but kind of squidgy in the camera output of the trinoc.

I’ll put one example below the fold.

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