Mary’s Monday Metazoan: What what spider butt!

via NatGeo

via NatGeo


  1. JohnnieCanuck says

    Darwin gets yet another call out. The BBC has a video interview with Dr. Simon Boxhall about the new island off Pakistan after the recent earthquake. He mentioned that Darwin had observed a similar dramatic change in the shoreline after the big earthquake in Chile while he was there on the Beagle and that he went on to speculate on movement of the Earth.

  2. Acolyte of Sagan says

    I was watching a spide spin a web in a tree last night (but had no Robert the Bruce-type imaginings as a result). If only my eyes had the resolution of the camera used for the shot above, it would have looked even more impressive.

  3. Acolyte of Sagan says

    That’s a ‘spider’ of course.
    Oh, for a time-sensitive edit function (hint).

  4. throwaway, gut-punched says

    I’ve got a Neoscona crucifera hanging out around my window. Also had a couple of large furrow spiders hanging around the front porch, but they’ve been absent lately. One interesting thing I learned while casually observing them is that they eat their webs once they become too unseemly. And they react to the sound of my shouty voice by rearing back ready to pounce. I’ve never been so insulted!

  5. gussnarp says

    So that’s what spinnerets look like up close? Cooooolllll. Definitely going to share this one with the kiddies.

  6. says


    I’ve got a Neoscona crucifera hanging out around my window.

    I have one of those right next the front window, she’s magnificent. I lightly mist her web once in a while so she can easily get a drink of water. She doesn’t like yelling either, but music doesn’t seem to disturb her.

  7. JohnnieCanuck says

    In this NW corner of the continent we don’t get that species of orbweaver. Instead we have Araneus diadematus, the cross spider. Huge and strong webs that make walking between the trees ‘interesting’.

    I have found that if you place a piece of meat like a dead insect or bit of hamburger in the web, the spider will do nothing. Now take an electric toothbrush handle or similar vibrator and touch it briefly to the meat. It will be quickly attacked and wrapped for later.

    A public service announcement for arachnophiles everywhere.

  8. Acolyte of Sagan says

    Johnnie Canuck / Caine, Fleur du mal; a spider that uses the ‘passive’ web (as opposed to such clever little buggers such as the bolas spider) will wait either in the centre or more commonly at the edge of its web, and will usually only respond to the repeat vibrations caused by an insect struggling to escape; only rarely will one react to a single vibration. By doing this, it doesn’t waste valuable energy rushing hither and thither every time a wind-blown leaf or seed is caught up.
    Also, without going to check, I think I’m right in saying that most spiders will paralyse rather than kill the prey before wrapping it so it stays fresh for longer, which is why they won’t often respond to pieces of hamburger or dead insects unless the web is artificially vibrated (again, if it isn’t moving, it’s probably not good to eat or has a limited shelf-life, so not really worth the expenditure of energy), and even then the vibration has to come from the area where the meat is since the spider will home in on the vibration rather than look to see where it’s coming from.

    What’s the betting I’m telling you nothing you didn’t already know?

  9. John Phillips, FCD says

    JohnnieCanuck, tuning forks also work as it’s the vibration making the spider think something has got caught in the web and struggling while something just placed there, like your piece of meat, won’t create any tell tale vibrations.

  10. Acolyte of Sagan says

    Aagh! Double ‘such’ in the first bloody sentence (see my post #5).

    Oh, and thank you mmierz for the link at #8.

  11. Acolyte of Sagan says

    Heh, between my constant failure to preview and your not refreshing before posting, I can’t see either of us running a ‘How To Do Internet Comments’ masterclass any time soon.

  12. says

    AoS, that’s why if there’s a spider in the house going hungry, it’s stunned flies. I still have a live trap from when we had mass aquaria and Severums, who prefer visibly live and struggling flies.

  13. Acolyte of Sagan says

    Caine, Fleur de mal; I think I’m right in saying that the spider’s mechanism for sensing movement of the web is so well developed, and the webs are so efficient at carrying vibrations, that it is able to pick up on the vibrations caused by the heartbeat of a stunned fly (how do you stun them, by the way; tell them you’re voting Republican next time around?).

    I have to say, though, that as much as I like spiders, and never object to them being around the house, it’s never crossed my mind to supplement their diets when they’re struggling to find prey (how can you even tell if one is hungry?), Much respect to you.

  14. says


    (how do you stun them, by the way; tell them you’re voting Republican next time around?).

    Hee, I wish that worked! Once a live trap has a good amount of them, stick them in a freezer for a short while, long enough to slow them waaaaaaaaaaaaaaay down, but not kill them. Take them out, feed to whatever is waiting.

    (how can you even tell if one is hungry?)

    Well, besides jumping spiders, the house is primarily inhabited by a variety of orb weavers. I’m in ND, and flies are pretty damn scarce over winter, so I tend to help out in the months leading up to winter time. Right now, the flies are absolutely terrible here, so everyone is pretty fat and healthy.

  15. throwaway, gut-punched says

    how do you stun them, by the way; tell them you’re voting Republican next time around?

    Not unless you also want to clean up their stomach contents.

    I watched one of my visitors dine on a rather juicy morsel tonight. Conveniently outside my bedroom window and right up nearly against it makes for easy viewing. She’s good to go for a few days I believe.

    I’m also wondering if I shouldn’t plant a leaf near, or on, the web for the N. crucifera since they supposedly make a cylinder out of them for their egg-sac, according to Wikipedia. She’s pretty far away from natural litter but leaves are starting to fall, not sure if any will reach her up on this second story, though.

    I completely wrecked a web the other day with my face while I was out in the garden. I love and respect all my arachnid friends but by the gods I will never not do the heeby-jeeby waving-hand dance when that happens.

  16. Acolyte of Sagan says

    Well I never, freshly chilled flies. I was thinking something altogether different, with images of you wielding a cushioned cudgel and trying to hit them with just the right amount of force to render them insensible, or maybe turning it into a game of skill with a pea-shooter.

    We always have several arachnid house guests, and because our house backs onto woodland there’s always plenty of bite-sized delicacies (for spiders, of course!) flitting in through the windows, particularly at night when the lights are on. The spiders have certainly worked this out as the curtain-poles by the windows followed by the light-shades are always the first places they spin their webs, and although some of our human visitors tend to look disapprovingly at them I leave them be*; I’d rather play host to a few well-fed spiders than a load of flies.
    One of our current ‘tenants’ comes out from behind a skirting board in the sitting room (US. family room?) every evening as the sun is going down. She (I’m assuming female as she’s bloody massive for a British house-spider ((including the legs she’s around 5 inches across)), probably the biggest I’ve seen, and females tend to be considerably larger than the males) has several webs on the go at any one time and she systematically visits each one in turn, first making repairs and then doing the rounds checking for fresh catches, which she wraps and takes back to her lair, always taking the shortest, most direct route, ofen directly across the floor. Now, I’m not saying she’s imposing but even our dog will move out of her way if he sees her coming in his direction – no kidding.

    *The exception being ‘abandoned’ webs, which are easy to tell as they very quickly build up a layer of dust, losing their adhesive properties and becoming both useless and inedible to their maker.

    Throwaway, gut-punched (curious ‘nym you have), I walk my dog in the woods every evening so often walk into webs. Whilst I have never really suffered the heeby-jeebies, having a rather wiry beard means that I often get home with what can seem like enough silk to make a pair of knickers caught up in it, along with whatever had already become ensnared in the web before I got there.
    The tensile strength of webs never ceases to amaze me. Often, a large and particularly industrious spider will spin one between trees either side of the pathway, and these ones tend to be quite extraordinarily strong, to the extent that I can blunder into one, feel the resistance and back out without damaging the structure in any significant way (except for the strands that my beard retains in its velcro-like way).

    Finally (At last! I hear you cry), when talking to those religionistas who insist that humans are their god’s ‘perfect’ creation, I like to use spiders as counter-examples, as in “Really? When you can shit out your own net to catch your food, rather than relying on technology – often requiring much time, lots of failures, and no small expense to develop and get right – which merely copies what spiders and other beasties do naturally but is rarely as efficient (and never as economical) as the natural model, then, and only then, might you have a point”.

  17. says


    Now, I’m not saying she’s imposing but even our dog will move out of her way if he sees her coming in his direction – no kidding.

    :D I have a running argument with one very large jumping spider who seems to be of the opinion that my face is a fine place to perch in the early morning hours. It’s one thing to be woken up by a rat shoving her nose up my nostril, quite another to have a spider poking about.