He’s not. These are just the facts, ma’am.
Pharyngula
Evolution, development, and random biological ejaculations from a godless liberal
He’s not. These are just the facts, ma’am.
I added a new female Parasteatoda to the laboratory colony — I hope she’s happy to have been brought in from the cold, especially since we have snow predicted for the end of the week.
She’s pretty.
My colleague, Chris Atkinson, told me yesterday that he’d been seeing a lot of spiders in his compost heap. “Interesting,” I thought. Then he sent me this photo:
WHOA. Look at all those spiders.
So I stopped by this morning (how could I not?), and the photo doesn’t do it justice. It is spider paradise. It’s a spider commune. There are all kinds of bugs living in the compost, and all over above them is a dense communal spider web, packed with spiders. I’d suspected it from the first picture, but I stuck my face down there and confirmed it — Steatoda borealis, the Northern Combfoot, which I’ve occasionally found while prowling about town, but this was the Mother Lode. I got a few closeups of one of their number in their web.
Usually, Jenny By-The-Front-Door is huddled up inside her nest, and at best I see a waving leg or three. Tonight, though, she made a rare appearance. Isn’t she beautiful?
I really want to dig into the intricate pigment patterns on Parasteatoda abdomens.
One day old. This was a tough photo to take — the little spiderlings respond to any touch with frantic escape behavior and end up running all over the place, and they refuse to pose nicely for a picture.
I note that even shortly after emergence they have the banded legs and scattering of dark abdominal pigment.
That’s right, #Arachtober is a thing with swarms of people posting photos of their fave spiders this month. It doesn’t seem quite right to me, because October is a sad month for spiders in Minnesota — I’m seeing them fading away as the weather cools and their prey declines and we approach the terrible frost and frigid winter. Here’s Jenny By-The-Front-Door, for instance.
I’ve been checking on her every day. She’s not very active; she’s huddled in her nest cobbled out of dead leaves and debris, and I can see her legs peeking out, and if I poke at the nest with my finger, she’ll slowly wave at me, but she’s nowhere near as busy as the spiders are in the warm summer months. I expect that one of these days I’ll give her a little poke and she won’t respond. She’ll either be in diapause or dead.
I still have lots of thriving spiders in the climate controlled environment of my lab, at least!
Yesterday, as we were traveling, we made a stop at a rest area to look for spiders, as one does. It was a terrible day for spider-kind, with intermittent rain and constant mist and cold, so it was mostly a fruitless search. I did find one sad, bedraggled looking Parasteatoda clinging to the underside of a handrail, with a fat drop of water beading up on her tattered web, and she fled as soon as my camera lens nudged in her direction. Just to make her day even worse, I then scooped up a couple of egg sacs she had in her nest, stealing her babies to bring back to the lab.
This morning as I grabbed the vial of sacs from the Big Spunk rest area to bring in to work, I noticed that they had hatched out! Baby spiderlings everywhere! They were probably triggered by being brought in to a nice warm house.
If someone is passing by Big Spunk today, could you stop in and tell their mama that her babies have found a good home, and we’ll take care of them? Probably more of these will survive here than they would in a drizzly empty wilderness where even the mosquitos weren’t flying.
I’ve been trying to keep an eye on the spiders living outside my house as fall transitions steadily into winter. It’s mildly tragic — the thriving summer population of Parasteatoda has been declining, and part of it, I suspect, has been competition and predation, and perhaps a bit of starvation. The mosquitos aren’t quite as thickly swarming as they were in the heat of the summer, and the funnel web spiders, with their grand sheets of webbing, have been edging out the cobweb spiders. The one I called Judy With-The-Big-Leaf who had captured a large, curled, dead leaf and was nesting inside it on the north corner of my house is gone now, and in her place are a couple of funnel webs with their silky tunnels extending in the gap between the siding and the rain gutters. I’ve noticed that Agelenopsis begins with web building down near the ground and expands upwards, so the only Parasteatoda left are in more elevated locations. Poor Judy, she built her nest fairly low to the ground and was overtaken by pushy late-comers.
Jenny By-The-Front-Door, on the other hand, has built a fortress on the wall above the front porch, at about chest height on me, and there don’t seem to be any competitors near by. She’s been building. Wind-blown leaves and seed pods are her construction material, and also some grainy clumps of, I think, insulation that were lying on the ground. She’s actually hoisted them up about a meter and a half to incorporate them, and has been stitching everything together with silk. Here’s her nest as it currently stands.
Can you spot her? I’ll reveal her location below the fold.
I’ve been wrestlin’ spiderlings all day, although they’re getting big enough that they’re showing sexual characteristics, like enlarged palps in the males, so maybe they’re more like spider-teens. They’re about three weeks old — I showed you the newly emerged S. triangulosa a while back. I’m currently raising three species (maybe four) of Theridiidae, P. tepidariorum, S. triangulosa, and S. borealis, and I’m seeing that some of the patterns emerge fairly early and in predictable ways.
This is P. tepidariorum, the most common of these spiders, and the one I’m raising for experimental studies in the lab. Some of its obvious characteristics are the mottled abdomen — although it’s still specifically patterned, as you might see from the clear left/right symmetry — and the dark banding around the limb joints. Less obviously from the photo, one other feature is that they build 3-dimensional webs that take full advantage of the space they’re in. When I open up the container, they’re hanging suspended in the middle of the space.
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