Snuggly spiders

The spiders were all fed this morning, and I continued my efforts to get breeding to happen. Maybe it did; I’d left the female New Arya (it’s a cursed name, we’ve gone through three Aryas so far, although this one seems to be lasting) with a male over the weekend, and initially I wasn’t certain what was going on. New Arya is slightly peculiar, having built a nest of debris in one corner of her cage, rarely leaving it. When last I left our two lovebirds, the male was hovering about the nest, plucking forlornly at the web, and New Arya was just waving a tootsie at him.

This morning, though, New Arya was outside (she’s on the left) near the male (on the right), and the two were just resting…in post-coital bliss, perhaps? I hope? I didn’t have the heart to break up the peaceful pair today, so I left them alone, for now. That male has more copulatory duties with other females, though, so I’m going to have to break them up this week.

See? Female spiders aren’t necessarily cannibalistic widow-makers.

Speaking of nesting, I found Mary Jane huddled in a corner with a dome built over her head. It looks cozy.

She seems quite content to have a home of her own. I suppose I’m going to have to introduce a male at some point, though, and wreck her maleless paradise.

Not a spider

I get complaints all the time about my spider photos. No matter how gorgeous they are, there are always a bunch of people who dislike seeing them. They’re not cats, you know? Everyone wants cats. Nothing but cats. Adorable little kittens frolicking about.

Well, PZ don’t do that. I’m willing to compromise, though, so here…a non-spider. It’s kind of the antithesis of a spider, which makes it more like a kitty cat. Enjoy your penis worms.

Here’s a big bucket full of penis worms.

And a beach covered with penis worms.

You like that, huh? You want more? ARE YOU HAPPY NOW??!? Are you going to continue criticizing my spiders?

Work, work, work, work

I played hooky last year, taking two semesters off (at half-pay, ouch) for this thing called a sabbatical. As it turns out, my university expects me to justify and explain myself and tell them what I did with my lazy time off, and I guess it’s not enough to fire off a quick note saying that I was playing with spiders. So now today I’m late for the division holiday party because I had to hammer out a longer rationalization. OK, sure, so I include it here, too, as well as mailing it off to my dean and division chair.

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That’s one beautiful spider

Latrodectus umbukwane is a breath-takingly gorgeous spider from South Africa. Look at those colors!

As you might guess from the genus, it’s related to black widows, which means of course everyone gets worked up about its potential venomous nature. It hasn’t bitten anyone that we know of! Get over it! It seems to be, if anything, unusually shy.

Also, you want to see some sexual dimorphism? Take a look at this.

I am not impressed with your anti-spider bigotry, Science Times

Well, this is a stupid sensationalist headline: New Species of Spider Found in Mexico Able to Rot Human Flesh. Yeah, so? This is a common property of many venoms, such as those in some wasps and snakes, and it makes sense that a spider, which relies on injecting toxins and enzymes that break down cells and tissues, would do so. How else would they slurp out the digested guts of their prey? These spiders have no interest in eating people, or “rotting human flesh”, so it’s an obnoxious way to distort the story.

I can just imagine spider tabloids running stories title “New Species of Primate Found With Large Fleshy Butts Capable of Crushing Innocent Spiders”. It completely misses the story.

Here’s a pic of the lovely beast in question.

It’s called Loxosceles tenochtitlan, and it’s distinguishing characteristic is not that it has a remarkable venom, but that males and females have unique genitals in a lock-and-key arrangement, which is also common in invertebrates.

In a statement released by the university, Valdez-Mondragon explained the difference: “As L.tenochtitlan is morphologically similar to L.misteca, it was initially thought that it had been introduced to this region by the shipping of ornamental plants. But when doing molecular biology studies of both species, we realized that they are different.” Valdez-Mondragon described the species and noted the difference between L.tenochtitlan and L.misteca lies in the male spider’s palp or the organ that enables touch in arachnids. It is also noted that the female L.tenochtitlan has a distinct looking sexual organ compared to L.misteca. Valdez-Mondragon explains that at first glance, the two species of spiders can look identical, but L.tenochtitlan can be identified because of its dark brown color which is dull compared to the other species and on its back is a very visible violin pattern.

The story goes on to claim that “humans are naturally repulsed at the sight of “creepy crawlies” like spiders.”

The Science Times is not one of my approved popular science sites. Too much trash written by people who have only the most passing acquaintance with science.

Spider story time

This is a brilliant idea, in principle. Maybe I need to start reading to the spiders.

Except…no, not Charlotte’s Web. The spider [spoiler] dies at the end [/spoiler]! This is not the inspiration I want to give the spiders. I’m trying to get them to breed, and telling them they’ll die afterwards isn’t exactly a great message.

Maybe I should read them this one.

Date night at the spider house

I have been neglecting my spiders this week — every day I get a little time with them, and then I realize I have to get grading done, and then I have to regretfully leave the lab to hunch over papers again. It’s unfortunate, too, because this is the week I’ve been trying to get them to breed, and there’s courtship to watch.

A little background: last year I had limited success with breeding because I was raising all the spiders in these 3cm diameter tubes, which is convenient and allows me to pack a lot of spiders into an incubator. The catch was that mating was fraught; put a male in a tube with a female and it was going to end in violence and cannibalism more often than not. Imagine that you wanted to study human courtship and mating, and your strategy was to keep women in those little capsule hotels, with plenty of food and water, and then every once in a while you picked some random guy and stuffed him into a capsule with a random woman, and then you planted a camera in the window to watch the fun. At best you’re going to see a strange and unrealistic version of mating…at worst, violence and death. Maybe cannibalism if you’re really lucky.

This year, I’m raising females in spacious cages where they can build large webs, and where there’s space to scamper off and be alone. I’m introducing males to these female-dominated spaces, and…well, so far it’s been less than exciting. It’s more like watching a junior high school dance. There’s a girl, hanging out over by the wall. Boy comes in to the gym, they notice each other, they look warily at one another. Their body language all says “I see you”, but they’re so nervous that you can’t tell whether they’re happy to see each other, or they’re threatening to vomit all over their shoes if they get too close.

The boy works up his nerve and approaches cautiously, sending as many friendly signals as he can. In spiders, this involves web plucking; they send vibrations down the web to each other. “Pluck pluck pluck?” he says. She fretfully replies “Pluck pluck pluckity pluck.” Is this promising? The boy is uncertain. “Pluck pluck,” he says, and reaches out with one arm, tentatively. “PLUCK!” she screams, and charges. Boy runs away. “Pluck pluck pluckin’ pluck pluck,” she hisses, in her position near the punch.

At least, that’s how I interpret this one encounter I watched.

We start out with the male spider center right; he’s advancing towards the female, top left, just out of view at first. He’s been plucking up a storm just before the clip, and both are slightly agitated. He reaches out to her and…devastating rebuff. He flees. She settles down, but continues to pluck at the web…sort of angrily, if I anthropomorphize. When he begins to approach again (off screen), she rushes out to chase him away.

I left the two of them alone after that. There was enough space in the cage that they could separate safely, and he was quick to run away, so she’d have to be strongly determined to kill and eat him to pursue, and I’d put plenty of fruit flies in the cage beforehand, so she wouldn’t be that hungry. I came back the next morning (it was like a junior high dance with a lock-in, and no chaperones!) and rescued the male, who was hovering maybe 6cm away, body oriented to the female and looking attentive. I have no idea if mating was accomplished.

That’s been my week. Introduce potential breeding pairs, watch a little angsty teen dating drama, scurry away to grade papers, come back to find two spiders staring at each other, giving no hint about what they’d been up to.

“How was your date, son?” “It was alright, I guess,” he replies, sullenly.

“How was your date, daughter?” She screeches angrily in spider. I don’t know what that means.


Good news! The male was left overnight with New Arya, one of my females who has built a cozy little nest with scraps of debris. When I just checked on them, the male was right outside the nest, tapping. New Arya was reaching out and waving at him. I decided to just leave him there a little longer and see what develops.

Also, Texanne of the triangulosa clan had made another egg sac. That’s three for her.