Clever, Those Salticidae

October 30, 2021 6:53 AM

Spiders are much smarter than you think – Cognition researchers are discovering surprising capabilities among a group of itsy-bitsy arachnids, Betsy Mason, Knowable, 10/30/2021. Jumping spiders, champs of cognition whose brains fit on the head of a pin, exhibit signs of intelligence like dogs or human toddlers. “Jumping spiders are remarkably clever animals,” says visual ecologist Nathan Morehouse, who studies the spiders at the University of Cincinnati. “I always find it delightful when something like a humble jumping spider punctures our sense of biological superiority.”
posted by cenoxo (38 comments total)

Now if they would just start weaving commentary in english into their webs. Charlotte where r u?
posted by sammyo at 7:56 AM on October 30, 2021 [1 favorite]

Jumping spiders don't weave webs! They hunt by chasing prey down after seeing it, kind of like a very visually focused big cat or a wolf. (They're more cursorial than cats, with less ambushing, but less social than most big cursorial ambush predators we know from mammals.)

I've spoken a few times with Sebastian Echeverri, one of Morehouse's grad students, and been to several of the lab's talks. The work they've done identifying spider visual targets and working out spider approach preferences (basically by suspending the spider from a pin and giving it a ping pong ball to walk on, such that you can see how quickly the spider wants to approach something and in what direction by measuring the rotation of the ball) is really creative and interesting.

Plus jumping spiders are fucking adorable. Those big round eyes!
posted by sciatrix at 8:49 AM on October 30, 2021 [13 favorites]

Ooh, actually a better analogy might be to a bird of prey like a falcon, except terrestrial.
posted by sciatrix at 8:59 AM on October 30, 2021 [4 favorites]

While Peter Watts' Echopraxia was a mostly-unenjoyable slog, the best part of it is a digression about Portia and how they think--the first time I'd ever been introduced the whole notion that...spiders think? But they do! This idea that their teensy brains are like an extremely slow computer that can only take a little bit of data at a time, but once it's done adding things up, it seems unearthly in its speed, navigation and precision...aiyee! It just makes them more cute, in their tiny deadly way! (Disclaimer: I'm very biased, we have a jumper in a terrarium to watch her hunt.)
posted by mittens at 9:35 AM on October 30, 2021 [9 favorites]

Can't let this one go by without recommending Children of Time, by Adrian Tchaikovsky, which, ah... explores the capabilities of Portia spiders.
posted by SirNovember at 9:39 AM on October 30, 2021 [16 favorites]

Peter Watts had thoughts about a spider.
posted by Splunge at 9:58 AM on October 30, 2021 [1 favorite]

Oh, hey mittens. ::wave::
posted by Splunge at 9:59 AM on October 30, 2021 [1 favorite]

spiders...can’t tell you what’s on their mind

I noticed a jumping spider perched on the plastic water bottle on my desk. At that moment, the spider began tapping insistently on the bottle. So I got a little bottle cap and put some water in it for him, and the spider came over and drank it.
posted by The Half Language Plant at 10:42 AM on October 30, 2021 [26 favorites]

Plus jumping spiders are fucking adorable. Those big round eyes!

Absolutely. The least sinister of their ilk.
posted by y2karl at 10:55 AM on October 30, 2021

Jumping spiders are so awesome. This article made me even more terrified of them but also more empathetic. I feel pity for intelligent animals who are so negatively impacted by humans and can’t do anything about it but stand back and watch their world being destroyed by greed. Anyway, why do spiders have so many eyes? Because the have no necks, so that makes sense. There’s no strong theory about why they have eight legs, some have 6 or 7 and aren’t ostensibly disabled. Have no eardrum, no problem, they can still hear you across the room! Leg hairs are sensitive to sound.

Shamble and colleagues made the discovery after succeeding in making direct electrical recordings from the brains of North American jumping spiders. This was a technical feat because the spider’s body is pressurised like an inflated tyre, meaning that previous attempts to record from their brains typically caused the spider to explode as soon as a hole was drilled in the outer shell.
posted by waving at 11:15 AM on October 30, 2021 [3 favorites]

I've had jumping spiders just hang it with me for an hour or so. One hopped up onto my hand, perfectly content to sit there as long as I didn't move it around too much.
posted by LindsayIrene at 11:16 AM on October 30, 2021 [4 favorites]

I feel pity for intelligent animals who are so negatively impacted by humans and can’t do anything about it but stand back and watch their world being destroyed by greed.

So, humans?
posted by rhooke at 11:32 AM on October 30, 2021 [2 favorites]

I've also had a bunch of chill experiences with jumping spiders. They don't seem to trigger my latent arachnophobia the same way as orb weavers or giant house spiders do and I suspect it's the small, furry and cute neoteny aspects of most jumping spiders.

A long time ago when digital cameras were still relatively new I had a relatively early model digital camera called a Ricoh 300Z that had a really nice macro function, so I spent a lot of time going around taking pictures of tiny things. The macro mode could focus so short it the focal distance was right up against the lens inside the housing and lens shroud of the camera. It was practically a portable digital microscope it was so good.

One day I was following this really tiny half centimeter sized little grey jumping spider around and it was very obviously aware of my presence and attention, and it kept following me and my camera around and like it was posing for glamor shots and closeups, waving it's forelegs around and just chilling in the rail of a patio balcony.

Meanwhile I'm watching it on the cameras relatively small 2.5" or so sized screen where it filled the whole frame.

That was all fine and good up until the point where the spider decided it had enough of being pestered and it reared up and made a really obvious threat display and then leaped right into the lens.

Which managed to scare the living daylights out of me because I was watching it on the screen, so it felt everything like a much larger spider several inches across had just jumped right into my face and was going for my eyeballs, causing me to yelp and instinctively drop and practically throw the camera away from me.

Which was, thankfully, safely strapped to my wrist, otherwise I would have dropped it off a third floor balcony and watched the camera shatter into a million little pieces in the brick courtyard below.
posted by loquacious at 11:32 AM on October 30, 2021 [17 favorites]

Jumping spiders are the best of companions. They can be playful, jumping around your hand and leaping to follow (translation: likely try to eat, but adorably so) a moving finger. I get a real Montaigne When I play with my cat, how do I know that she is not playing with me rather than I with her? vibe from them.

We get a variety of them, from compact zebra jumpers (Salticus scenicus), through industrious ant mimics (Myrmarachne formicaria, probably) and flat but ornate tan jumpers (Platycryptus undatus) up to the large, fuzzy and adorably pugnacious bold jumpers (Phidippus audax). There's also a tiny species we get that I can't identify. I love 'em all.

Extremely pretty salticid waves hello: Habronattus hallani
posted by scruss at 12:05 PM on October 30, 2021 [3 favorites]

They do seem to identify the camera lens itself as the moving thing to try it on with. You could do a real rad supercut video of clips of "cat nose probes camera" with a tasteful mix of "jumping spider occupies camera."
posted by away for regrooving at 12:06 PM on October 30, 2021

They do seem to identify the camera lens itself as the moving thing to try it on with. You could do a real rad supercut video of clips of "cat nose probes camera" with a tasteful mix of "jumping spider occupies camera."

Yeah, I can totally buy the concept they see a camera lens as an eye spot, especially the smallish lens of my old point and shoot.

There's also the possibility that my hands holding a silvery-grey oblong camera body with a black, reflective and slightly iridescent lens from the anti-reflective coatings on it would be more than a little suggestive of something that looked like a spider, and this is before we even consider the idea that the spider might be smart enough to recognize a large human animal looming over them.

And it certainly didn't help that I was waving my fingers back at the jumping spider like forelegs and mirroring what it was doing just like one naturally ought to do when a spider waves at you.

For all I know I gravely insulted the spider's mother and ancestors or called them a bug or it didn't like my accent or something.
posted by loquacious at 12:51 PM on October 30, 2021 [2 favorites]

One thing I thought everyone agreed on in the blue, being smart doesn't get you off the hook for being a creepy fucker?
posted by biffa at 3:28 PM on October 30, 2021

Who's being a creepy fucker? There's nothing a jumping spider does that my dog or cat wouldn't do just as gleefully.

If you're doing a general "spiders are scary/gross/bad" thing, maybe not in a thread explicitly celebrating how cool jumping spiders are?
posted by sciatrix at 3:33 PM on October 30, 2021 [4 favorites]

Sciatrix maybe that’s a little harsh? I took biffa’s comment as a pretty funny joke. Plus apparently it would take a Portia awhile to sequentially process the jab and be offended 😁
posted by sixswitch at 3:54 PM on October 30, 2021

I realize I just described a sort of esprit d’escalier d’arachnide but maybe the spider would still be calculating how to get out the door and wouldn’t actually be on the stairs when it realizes how it should have responded to the insult
posted by sixswitch at 3:58 PM on October 30, 2021 [1 favorite]

One thing I thought everyone agreed on in the blue, being smart doesn't get you off the hook for being a creepy fucker?

Dear mods: Can we move this comment over to the Facebook/Meta thread and then we all pretend biffa is lost and in the wrong thread?
posted by loquacious at 4:48 PM on October 30, 2021 [4 favorites]

A great podcast recently came out featuring Sebastian Echeverri: https://www.alieward.com/ologies/dancingspiders
posted by gray17 at 4:52 PM on October 30, 2021 [1 favorite]

spiders...can’t tell you what’s on their mind

I noticed a jumping spider perched on the plastic water bottle on my desk. At that moment, the spider began tapping insistently on the bottle. So I got a little bottle cap and put some water in it for him, and the spider came over and drank it.

My previous house had 13 foot ceilings and lots of Pholcus spiders. For some reason every time I would take a shower one would come down from the ceiling. One time, thinking it was thirsty and the moisture attracted it, I flicked a drop of water next to it. The spider took a long drink and went back up the wall! After that I'd flick a drop of water next to any spider that showed up and invariably they would have a drink.

I don't live in a spider house any more. Possibly because we have cats.
posted by oneirodynia at 5:13 PM on October 30, 2021 [3 favorites]

When it's mating season, male Peacock Spiders have all the right moves for stayin' alive.
posted by cenoxo at 6:34 PM on October 30, 2021 [1 favorite]

Spiders must drink water to live and move — Spider Legs and How They Work - Spider Legs: Hydraulics in Action, Infinite Spider; December 16, 2014:

...Humans only have one major joint per limb (knee, elbow, etc), but spiders have seven joints for each leg. The upshot to having a multi jointed exoskeleton is that spiders don't have the support of bones for a flotilla of flexors and extensors. There isn't enough room inside their bodies for attachment, and even if there was, all those muscles would make them super heavy and lumbering. On top of that spiders wouldn't have enough energy to keep those muscles warm (it's rough being a "cold blooded" creature) nor enough oxygen to support a large number of muscles.

...how do they push their legs outward to run, jump, and move without extensors? The answer is hydraulic pressure. A skeleton's body is filled with a fluid that is like blood (though some what different) called hemolymph [WP]. If you remember, spiders only have two body parts, the first is the fused head and middle, called a cephalothorax (#2 below). The other is their abdomen (#3).

All eight spider legs are attached to the cephalothroax for a good reason. Each leg's outward movement is controlled through the cephalothroax, which regulates the hydraulic movement and pressure hemolymph. Spiders don't need extensor muscles because they can use fluid movement/hydraulics to "push" out their legs. The cephalothorax acts something like a very finely-tuned, fluid-filled bellows that pushes hemolymph around the body of the spider in a fraction of a second....

One of the reasons that spiders are naturally skittish and afraid of humans (read predators) is because they rely on hydrostatic pressure in their skeleton. If they are punctured or lose a leg, they risk losing their pressure and literally deflating.
posted by cenoxo at 7:31 PM on October 30, 2021 [6 favorites]

They do seem to identify the camera lens itself as the moving thing to try it on with.

Jumping spiders have excellent vision. As with a mirror, perhaps they see their reflection in a camera lens and try to interact with it.
posted by cenoxo at 7:49 PM on October 30, 2021 [2 favorites]

A Salticid is the smallest creature that can look a human in the eye. Try it, you'll see. But don't get all pushy about it, sometimes we just want to be left alone.
posted by SaltySalticid at 8:56 PM on October 30, 2021 [15 favorites]

Whenever you're face-to-face with any Salticid and look them right in the eyes, they're looking right back atcha when their two large eyes (which have independently movable eye cones) turn completely black. Whatever you do, never be the first one to look away.
posted by cenoxo at 9:39 PM on October 30, 2021 [1 favorite]

It's amazing to me how *efficient* cognition can be. We carry around this giant very expensive wetware to do our work, but birds manage to be extraordinarily smart with only a tablespoon or so of brain. And jumping spiders manage to plan with only a pinhead's worth of brain.
posted by tavella at 11:39 PM on October 30, 2021 [4 favorites]

If jumping spiders are hunters, I guess we could see ogre-faced net-casting spiders as fishers.

The linked video out of Cornell and shot in Florida claims they have the biggest eyes found in spiders (meant proportionately, perhaps?), but they can also catch flying insects out of the air by casting their net backwards, relying apparently only on sound to locate their prey.
posted by jamjam at 12:29 AM on October 31, 2021 [1 favorite]

And I bet they use that net like a parasail to get around, too.
posted by jamjam at 12:32 AM on October 31, 2021

jamjam – Your (amazing) YouTube link is borked. It should be:

Ogre-faced, net-casting spiders catch prey in dark of night
https://www.youtube.com/watch?v=RmP2Wth3OTA

posted by cenoxo at 4:14 AM on October 31, 2021 [1 favorite]

Another net-caster with a different technique: The Bolas Spider.
posted by cenoxo at 4:35 AM on October 31, 2021

Sciatrix:

Plus jumping spiders are fucking adorable. Those big round eyes!

Damn straight they are adorable. I am delighted that Lucas the Spider is actually pretty successful. Perhaps we will someday have a world, where each and every Metafilter post about arachnids does not contain posts from people, who simply must share that they find spiders creepy.
posted by bouvin at 11:16 AM on October 31, 2021 [3 favorites]

I'm a fanboi of jumping spiders for over 50 years, but admit that The Eyes of Portia Schultzi (WP) would be a creepy movie (BBC Earth YT) on a big screen. Doesn't mean they're not fascinating, though.
posted by cenoxo at 3:46 PM on October 31, 2021

sammyo > Now if they would just start weaving commentary in english into their webs.

Humans may be ignorant, but birds and bees understand webspeak: Web Decorations Warn Birds – Orb-weaver spiders, Ask Nature, Andy Carstens, October 16, 2016.
posted by cenoxo at 6:20 AM on November 1, 2021

A good take on the article from spider biologist (and godless liberal) P. Z. Myers.
posted by TedW at 7:09 AM on November 1, 2021

TedW > “It’s not so much the size of the brain that matters, but what the animal can do with what it’s got,” says arachnologist Fiona Cross of the University of Canterbury in Christchurch, New Zealand."

"Go to the ant spider, thou sluggard; consider her ways, and be wise: which having no guide, overseer, or ruler, provideth her meat in the summer, and gathereth her food in the harvest." [With apologies to Proverbs 6:6-8, KJV.]
posted by cenoxo at 8:08 AM on November 1, 2021 [1 favorite]