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A spider web unlike any seen before

nytimes.com

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Re: A spider web unlike any seen before

#101

Post by perihelions »

barryvan wrote: post #8
Lio wrote: post #6

This is fascinating. My first question would be what are they catching? What can sustain that number of spiders so far underground?

From the article: > The vast spider population is attributed to an abundant food supply: more than 2.4 million midges in the cave, ready to be entangled in the intricate web. ...although I guess the question then is what sustains the millions of midges!

That's the interesting part! (And which the submitted NYT story regrettably neglects). It's a chemoautotrophic ecosystem[0] largely independent of the sun, and of photosynthetic life.

Akin to hydrothermal vents[1] in the ocean, and the lifeforms that eat that effluent.

[0] https://subtbiol.pensoft.net/article/162344/ ("An extraordinary colonial spider community in Sulfur Cave (Albania/Greece) sustained by chemoautotrophy")

> "Stable isotope analyses (δ¹³C and δ¹⁵N) revealed that the trophic web sustaining this assemblage is fueled by in situ primary production from sulfur-oxidizing microbial biofilms then transferred through chironomid larvae and adults to higher trophic levels."

[1] https://en.wikipedia.org/wiki/Hydrothermal_vent

Re: A spider web unlike any seen before

#102

Post by voidfunc »

bob1029 wrote: post #45
colordrops wrote: post #25

Earlier quoted context omitted.

Yeah same, we do not bother spiders in the house unless they jump into bed or on food or whatever, and then we just take them outside. With spiders and cats in the house we never see any flies or other insects.

I have a rule with the spiders where if they get too bold they get the vacuum. I don't mind them lurking in the corners but I don't want them crawling across my desk. I think most of them understand the arrangement by now. Only occasional enforcement is necessary.

I'm sure putting it outside makes you feel better but it's a death sentence regardless for most house spiders to be put into the outdoors.

Re: A spider web unlike any seen before

#103

Post by InsideOutSanta »

_qua wrote: post #46
colordrops wrote: post #25

Earlier quoted context omitted.

Yeah same, we do not bother spiders in the house unless they jump into bed or on food or whatever, and then we just take them outside. With spiders and cats in the house we never see any flies or other insects.

I've never really understood the "spiders protect you from pests" argument. Yeah, sure they eat flies. But I'd much rather have a fly buzz past me and get stuck to some fly paper than have a spider drop from the door frame on an invisible silk thread and slam into my face, or run across my pillow. Maybe I have arachnophobia, but they're freaky little creatures that I don't want in my living space.

I don't mind spiders at all, they mostly stay out of my way. Flies, on the other hand, land on my food, buzz around the room when I want to sleep, and are generally a nuisance.

Re: A spider web unlike any seen before

#104

Post by cindyllm »

PaulHoule wrote: post #91
bob1029 wrote: post #45

Earlier quoted context omitted.

I have a rule with the spiders where if they get too bold they get the vacuum. I don't mind them lurking in the corners but I don't want them crawling across my desk. I think most of them understand the arrangement by now. Only occasional enforcement is necessary.

I feel guilty when I take down the webs. Wool dusters work as well as the vac. Lately I have been trying to get macro photos of spiders hanging on their threads and so far failing because they see the camera and drop down a foot before I can set up the shot.

[dead]

Re: A spider web unlike any seen before

#106

Post by n4r9 »

nicbou wrote: post #50
functionmouse wrote: post #38

Earlier quoted context omitted.

Not "we", it's the billionaires.

They produce the goods that we consume. We are the ones working in their marketing department, building their online stores, streamlining consumption. Then we go home and buy stuff we don't need.

They only "produce" anything in an abstract economic sense.

Re: A spider web unlike any seen before

#107

Post by BirAdam »

acomjean wrote: post #47
thaumasiotes wrote: post #41

> The team of scientists discovered that 69,000 Tegenaria domestica , known as the barn funnel weaver, were living with about 42,000 Prinerigone vagans , which inhabit wet places. Usually the barn funnel weavers prey on P. vagans , which are smaller. > “But in the cave, because it’s dark in there, our hypothesis was that they do not see each other,” Blerina Vrenozi, a biologist, zoologist and ecologist at the Univers…

I think you are right. If I remember there were 2 types of silk, and they could use their legs to “listen” to vibrations when something gets caught anywhere in the web. They seem to avoid getting stuck in their own webs. But they do have 8 eyes, so I’m assuming they make visual confirmation. But these cave spiders are in the dark…

Depending upon the species, spiders can make more types of silk: strong, soft, sticking, sensing, etc.

Most spiders have terrible eyesight despite having eight eyes. Those with good eyesight are jumping spiders, portia, and a few ground spiders. These species are easily distinguished by having two large front-facing eyes.

Due to bad eyesight, most spiders use touch through their webs and/or hairs. The hirsute species can easily identify pretty much anything that causes a wind current near them, and most all species can easily identify prey by the distinct vibrations they make once caught in the web.

If you watch most spiders, however, they can occasionally be fooled on windy day when a leaf or other detritus hits their webs, and they have to go touch it to find out it isn't prey. Eyesight just isn't a thing most are great with.

Re: A spider web unlike any seen before

#108

Post by thaumasiotes »

atlintots wrote: post #94
loloquwowndueo wrote: post #81

Earlier quoted context omitted.

> I'd much rather have a fly buzz past me Ever wonder where those flies have been? Maybe on some nice smelly garbage, and then on your food or your dishes. Flies carry diseases, man. > and get stuck to some fly paper Glue traps are cruel.

Aren't spider webs kind of like glue traps

I saw a butterfly get stuck to a web once. It immediately started hurling itself violently away, trying to shake itself free. The spider was not immediately in evidence.

I managed to take the web off it, but not without tearing off the part of the wing that made contact. I assume that in the butterfly's best-case scenario, that would have happened anyway. It was able to fly afterwards.

Re: A spider web unlike any seen before

#109

Post by thaumasiotes »

bulletsvshumans wrote: post #56
thaumasiotes wrote: post #41

> The team of scientists discovered that 69,000 Tegenaria domestica , known as the barn funnel weaver, were living with about 42,000 Prinerigone vagans , which inhabit wet places. Usually the barn funnel weavers prey on P. vagans , which are smaller. > “But in the cave, because it’s dark in there, our hypothesis was that they do not see each other,” Blerina Vrenozi, a biologist, zoologist and ecologist at the Univers…

Maybe the glut of conventional food leaves the prospect of eating their compatriots less appetizing.

Probably not; these aren't closely related spiders. It would be like a human eating a monkey, which is something humans like doing.

But if the smaller spiders can fight back at all, it might well make that battle less appealing.

Re: A spider web unlike any seen before

#110

Post by sheepscreek »

ysavir wrote: post #83
sheepscreek wrote: post #70

Earlier quoted context omitted.

> than have a spider drop from the door frame on an invisible silk thread and slam into my face, or run across my pillow Rare if ever happens. Maybe 5 times in your life time. I will pay that cost any day. I have made friends with spiders. Flies spread diseases, spiders eat them. Spiders seldom bite humans and when they do, it’s nowhere near as bad as getting scratched by a cat.

For what it's worth, it happens to me about 5 times each summer. But I also welcome spiders as pest control, so it's not a surprise, and I forget all about it 5 seconds later.

You should make friends with Canadian spiders then. They are very polite. I don’t remember the last time I got bit :)
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