Exciting! News! From the Spider Lab!


Well, I found it exciting anyway. One of the problems I’ve faced in my new research on local spiders is that I can’t tell two species apart, Parasteatoda tepidariorum and Parasteatoda tabulata. Even the expert sources I consult usually discriminate by dissecting their genitals, which is not useful for me, since I want to study live animals and embryos. There is one suggestive hint, though: P. tabulata builds funky little nests in their webs in the wild, while P. tepidariorum apparently does not. It’s a behavioral distinction, and I have no idea how definitive it is, but at least it’s an angle.

Unfortunately, I haven’t been able to see nest building in the lab. I’ve tried throwing in miscellaneous office debris, like stuff from a whole punch and a paper shredder, but they never pay attention to it. Maybe all of my lab animals are P. tep? Maybe I’m providing the wrong kinds of nest material? I dunno.

So yesterday, in a forlorn, half-assed try, I noticed all the fine wood shavings in the containers for wax worms, their food, and I sprinkled a few small shavings in the cage for one of the new generation of spiders, not yet named, and went home. I’d spread them around, and even avoided the place where she was currently nesting (spiders have preferred spots to hang out in).

Today, presto…she had gathered the majority of shavings into one central place, and had built a nest. Isn’t it beautiful?

You can’t see her in there, because she’s hiding. You can see her brown egg sac, near the top center of the nest. I’ve also highlighted the cobweb by misting it with water. I guess I was just failing to give them the correct home-building materials before.

This is excellent news! Now I have to give all of the spiders in my colony some wood shavings, and see if they fall into two groups, nest-builders and non-nest-builders. I have a student who proposed studying this distinction this summer, if that still happens in this age of pandemic, and one thing we’ll have to try is a nest construction time-lapse — that really was assembled overnight, so it’s speedy, but it was done in the dark, so we’ll have to play with cameras and lighting to see if we can observe it.

The bad news is that when Tabitha — she has a name now — dies, we’re going to have to dissect her and observe her genitals very closely, to independently confirm her species.

Otherwise, though, this is so exciting! Thrilling, even! All the spiders get wood shavings! Everyone gets wood shavings! You can have wood shavings! Come on, you’ve got to admit that complex nest construction behavior in an invertebrate is fun stuff, even if it’s totally unsurprising, given that spiders have always been elaborate builders.

P.S. You might actually be able to see a bit of spider anatomy poking out in one place, but I’ll leave it as an exercise for you to Find the Spider.

Comments

  1. jrkrideau says

    Is that thing going to pass the building inspector? Does Tabatha even have a licence for that?

  2. wzrd1 says

    See if your camera will respond to an IR illuminator. They’re fairly inexpensive online and would make photography in the dark a snap – assuming the species doesn’t see in near-IR.

  3. JimB says

    Hmmm. The spider wouldn’t build her house out of paper. In Minnesota. But she did go for the wood. Sounds like a smart spider.

    Try some concrete, she’ll make a castle…

  4. JimB says

    PZ,
    You ever looked at the Raspberry Pi? A Raspberry Pi and camera would only run a bit over $100. All the code for time delayed photography is available online. Or you write your own.

  5. says

    That’s what I’m thinking of — Raspberry Pi + NoIR camera kit + 850nm LED light. It’s not feasible right now, but maybe later this summer I can tinker a bit.

  6. JimB says

    They are a lot of fun. I got one last year for my birthday. I figure this will be something I can show my granddaughter. Get her interested in computers. Well, she’s going to be born in the next couple of weeks, so I’ve got a couple of years to figure it out.

  7. lochaber says

    huh, that’s pretty cool.

    I imagine you get plenty of material with your waxworm shipments, but otherwise I wonder if the shavings from a pencil sharpener would work, or if the paint and graphite would cause issues, or maybe they are the wrong size/shape? Do schools still have pencil sharpeners?

    anyways, if you ever do get around to getting a vid, I’d love to see it…

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