Mary’s Monday Metazoan: What’s in your walls?

A guy finds a hole in his wall, and behind it, a strange leathery brown mass. He pulls it out — first mistake. He cuts it open — second mistake. Within…


It’s a wasp nest stuffed full of dead spiders, each with an egg planted in them. It’s just adorable. There are more photos. I was kind and picked the least horrific.


  1. John Phillips, FCD says

    Paralysed. The eggs hatch out and even avoid vital organs until the very last so as not to actually kill the host spider too soon.

  2. Tethys says

    Ichnuemonidae are actually my favorite group of insects, along with wasps and bees in general. I have several species that I try to provide good food and nesting habitat, and they in turn provide pest control and pollination services. If sure if I went looking for their overwintering mudballs I would find them.

    In my walls? My house is over 100 years old and I have big-headed ants, two kinds of bats, and a flying squirrel who all call it home. I wish I could get rid of the ants.

  3. says

    Thank goodness for steel concrete — Giliell, professional cynic -Ilk-

    You’d think that, wouldn’t you?

    I’m, I’m simply saying that life, uh… finds a way. — Dr. Ian Malcolm

    Be afraid. Be very afraid. — Veronica Quaife

  4. says

    To answer the question in the title: mostly mortar, bricks and polystyrol.

    These creatures are proof positive that loving and benevolent god does not exist.

  5. wzrd1 says

    So, I open my mail and find the link to this entry. I was hungry when I opened the page.
    I’m still hungry. It’s nature up close, through a macro lens. :)
    I have around a dozen such nests, as well as several other types of wasp nest on my property. I leave the wasps alone and if they don’t, that trait won’t be selected for.
    For, if they’re so aggressive that my presence in my back yard can’t be tolerated 5 meters away, the wasp nest will be gone with a nerve agent – aka insecticide.
    Otherwise, I leave them alone, they leave me alone.
    Inside the house, that’s another story entirely. The same is true in the garage, where a hidden nest seems to be. I opened it up, noticed a half dozen large wasps. I closed the garage and rolled a few foggers in. Inside is mine, outside can be shared.

    As for creator jokes, I’ve cited the platypus as an example of a sense of humor. That’s both due to its physical morphology and its genetics. But, jokes are just that, jokes. :)

  6. =8)-DX says

    Haven’t you people ever played Diablo 2? Ickle bickle pawalyzed spidewz ‘n ickle bickle mommy wasp’s nice lickle ‘ousey.

  7. jeffj says

    In my experience these are relatively docile for wasps. Unless you’re a spider, of course. I’ve read that their sting isn’t very painful. Around here we have yellow & black and a rather pretty shiny blue variety, both of which I’ve always called (quite incorrectly, I’m sure) spider wasps.

    Now yellow jackets – those guys are the real jerks. They want your food and are willing to fight you for it.

  8. brucej says

    Around here we have some of the pretty, shiny blue and orange variety: that have one of the the most painful stings in the world, per the Schmidt* pain index. It has been described as ‘like being stabbed with a white-hot 16d nail carrying 20,000 volts’ it will stop you in your tracks. Fortunately it subsides within a very short time.

    *(Justin won a well-deserved IgNobel for that work this year in the Physiology and Entomology category)

  9. brucegee1962 says

    I remember that, according to Miss Frizzle and the Magic Schoolbus, you’re never more than two or three feet from a spider. And possibly a wasp egg, apparently.

  10. wzrd1 says

    @22, where we’re now living, that’s remarkably close. I’ll have to sit down and actually count the number of wasp species in the area, but based upon different nest types, it’s around 8 for a minimum.
    To judge from the large number of other insect types, perhaps I should build a bat house.