Oh no, I’m home alone » « The tastiest part of a cockroach is its heart

No anthropophagy among spiders, yet. That we know of.

I thought you might want to know that Spiders feeding on vertebrates is more common and widespread than previously thought, geographically and taxonomically. Not that I want you to worry or anything, but you should know that vertebrates like you are prey to certain spiders. (Not you, personally, of course — just your smaller, weaker cousins.)

You might be wondering who the killer spiders are, and you’re in luck: here’s a table of the spider families that will kill your relatives.

Frequency distribution of 39 spider families engaged in vertebrate predation based on cummulative literature data (source: McCormick & Polis 1982; Brooks 2012; Nyffeler & Kno ̈rnschild 2013; Nyffeler & Pusey 2014; Nyffeler et al. 2017a, 2021; Nyffeler & Vetter 2018; Weisberger 2019; Nyffeler & Altig 2020; Reyes-Olivares et al. 2020; Fulgence et al. 2021; Nyffeler & Gibbons 2021, 2022; Google Scholar & Google Picture Survey for Sparassidae feeding on vertebrates 2021). The ten spider families Atracidae, Theridiidae, Pisauridae, Ctenidae, Theraphosidae, Nephilidae, Araneidae, Lycosidae, Sparassidae, and Trechaleidae are the most prominent vertebrate-eaters (combined 91% of a total of 966 recorded incidents). *The number of records for Atracidae (n 1⁄4 20) presented here is an underestimate [The atracid Hadronyche formidabilis must be considered to be a habitual frog-eater due to the fact that countless frog bones had been found in funnels of this species which not could be taken into account in this graph (McKeown 1952)].

See? No worries. You probably don’t even recognize most of those names.

I’m here to inform you that the number one culprit, the Theridiidae, also known as the tangle-web spiders or comb-footed spiders, are also among the most common house spiders. The spiders I raise in large numbers in the lab, the Steatodas and Parasteatodas and Latrodectus, all belong to this family, and I’ve long noted their ability to bring down animals much larger than themselves with their potent venom and most excellent cobwebs.

Not you, of course. You can continue to sleep well at night, knowing that the spiders living in your attic and basement are not going to eat you. Not unless they grow significantly larger, or form significant and numerous cooperative colonies.

My spiders do get along well with each other, so there are possibilities…

If you doubt me, here are some spiders eating birds, bats, frogs, fish, and snakes. Yum.

Examples of habitually vertebrate-eating spiders – A. Argiope aurantia Lucas, 1833 feeding on a female ruby throated hummingbird (Archilochus colubris) in front of a house in College Station, Texas (Photo by Donell S. Frank). B. Nephila pilipes (Fabricius, 1793) feeding on a small bat (superfamily Rhinolophoidea) entangled in the spider’s web; incident observed at the top of the Cockatoo Hill near Cape Tribulation, Queensland, Australia (Photo by Carmen Fabro). C. Megadolomedes australianus (L. Koch, 1865) (Pisauridae) feeding on a Graceful Tree Frog (Litoria gracilenta) in Barratt Creek, Queensland, Australia (Photo by Barbara Maslen ‘‘Wild Wings & Swampy Things Nature Refuge, Daintree’’). D. Adult male of Ancylometes sp.(possibly Ancylometes rufus (Walckenaer, 1837)) caught a characiform fish (Cyphocharax sp.) near Samona Lodge, Cuyabeno Wildlife Reserve, Ecuador (Photo by Ed Germain, Sydney). E. Adult female black widow (Latrodectus hesperus) feeding on a subadult coral snake Micruroides euryxanthus (Elapidae) near the Boyce Thompson Arboretum, Superior, Arizona, USA (Photo by Lawrence L. C. Jones).

But don’t worry, they aren’t eating people yet!

Nyffeler M, Gibbons JW (2022) Spiders feeding on vertebrates is more common and widespread than previously thought, geographically and taxonomically. Journal of Arachnology 50:121–134.

Oh no, I’m home alone » « The tastiest part of a cockroach is its heart

Comments

  1. birgerjohansson says

    I am not worried about being eaten. I am worried about being killed by a spider with a ridicilously potent venom.

  2. Pierce R. Butler says

    I first misread the headline as “No anthropology among spiders…” and had some serious doubts.

    Surely they study us quite carefully, even if they conceal their notes.

  3. wzrd1 says

    I’m aware of one spider that is known to occasionally take a nice pinch of flesh from humans that vex them, but camel spiders are an exception to a few rules and biting an offender is decidedly not trying to eat someone.

    Now, I’ve gotten a nice snack this afternoon. Ran into a sockpuppet on Wiki, been a pain on the Cloning article, twice banned and one remaining sock seems to be about and got reverted and now reported.

  7. Walter Solomon says

    birgerjohansson #1

    Coral snakes have ‘ridiculously potent venom’ so the black widow is doing a service here by eating it.

  8. beholder says

    But don’t worry, they aren’t eating people yet!

    First they came for the arachnophobes who still read PZ’s blog, and I laughed and grabbed a bucket of popcorn, because I’m not an arachnophobe.

    Then they came for me, and I didn’t really mind, because humans are delicious and I always knew spiders would do a better job ruling this planet than humans have done.

  9. drewl, Mental Toss Flycoon says

    Thanks for posting cool spider pics.
    (spider-pics, spider-pics, does whatever a spider-pic does)…

  22. Rob Grigjanis says

    Ancylometes and the more fully aquatic Argyroneta are the only known genera of spiders that can spin webs in water. Though these webs can catch fish, they mostly prey on fish by diving down or lying in wait until prey passes within striking distance. Once caught, these spiders will bring their prey back to the surface before eating it.

    https://en.wikipedia.org/wiki/Ancylometes

  23. nomdeplume says

    Yep, all very amusing I guess, but think of the terror of those vertebrate animals `as they realised they were trapped, couldn’t free themselves, and then saw the spider approach, wrap them and poison them.

  25. Silentbob says

    @ 23

    Dude trust me we’re thinking about it. That’s why PZ ‘s posting this stuff for Halloween.
    (Don’t make me post *that* scene from The Fly again.)