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Newly discovered spider builds spring loaded snare to catch ants

phys.org

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Re: Newly discovered spider builds spring loaded snare to catch ants

#31

Post by addandsubtract »

pvaldes wrote: post #9
Foskya wrote: post #4

It is truly fascinating, I wonder how it evolved like that. Before becoming a spring as it is today how was it hunting in the past? What constraints made it need such a mechanism instead of a typical web?

Injured Himenoptera are known to send pheromones that trigger a vicious defensive response from other members of the colony. On a typical web the companion ants would do what the ants do. Go to war and flood the place surrounding the danger until eventually killing it. The spider does not have neither the stamina, nor the venom amount to deal with that. This web is designed to extract just one ant, while cutting the…

> Notice that the spider is carefully moving out of the way, just a second before the ant is launched.

It's not moving before the ant is launched. It's moving as soon as the tension in the web is gone, ie. there's movement in their web. Most spiders react to movement in their web.

Re: Newly discovered spider builds spring loaded snare to catch ants

#33

Post by pvaldes »

addandsubtract wrote: post #31
pvaldes wrote: post #9

Earlier quoted context omitted.

Injured Himenoptera are known to send pheromones that trigger a vicious defensive response from other members of the colony. On a typical web the companion ants would do what the ants do. Go to war and flood the place surrounding the danger until eventually killing it. The spider does not have neither the stamina, nor the venom amount to deal with that. This web is designed to extract just one ant, while cutting the…

> Notice that the spider is carefully moving out of the way, just a second before the ant is launched. It's not moving before the ant is launched. It's moving as soon as the tension in the web is gone, ie. there's movement in their web. Most spiders react to movement in their web.

May be an effect of the video being show in slow motion. Good point. Then this spider is ultra-fast.

Re: Newly discovered spider builds spring loaded snare to catch ants

#34

Post by spidercat »

NitpickLawyer wrote: post #24

Heh, for a second there this read like some of the Portiid adventures with Bianca and Fabian from Adrian Tchaikovsky's book "Children of time". If you find this kind of thing interesting and are a fan of sci-fi, I highly recommend the book.

Children of Time is one of the best books I've ever read, it's honestly amazing. It might be my all-time favorite. Seconding this recommendation!

Re: Newly discovered spider builds spring loaded snare to catch ants

#35

Post by zacharyfmarion »

spidercat wrote: post #34
NitpickLawyer wrote: post #24

Heh, for a second there this read like some of the Portiid adventures with Bianca and Fabian from Adrian Tchaikovsky's book "Children of time". If you find this kind of thing interesting and are a fan of sci-fi, I highly recommend the book.

Children of Time is one of the best books I've ever read, it's honestly amazing. It might be my all-time favorite. Seconding this recommendation!

Thirding it! This is your sign, go read it

Re: Newly discovered spider builds spring loaded snare to catch ants

#36

Post by vharuck »

sethammons wrote: post #13
pvaldes wrote: post #9

Earlier quoted context omitted.

Injured Himenoptera are known to send pheromones that trigger a vicious defensive response from other members of the colony. On a typical web the companion ants would do what the ants do. Go to war and flood the place surrounding the danger until eventually killing it. The spider does not have neither the stamina, nor the venom amount to deal with that. This web is designed to extract just one ant, while cutting the…

The smart spider is portia, a jumping spider. A quick search uncovers zounds of videos, articles, and scientific publications on them. They specialize is hunting spiders, changing hunting tactics based on type and number of prey. Yes, they count. They strategize. They make multi-step plans that take them out of sight of prey. And some people keep them as pets.

>And some people keep them as pets.

I can personally vouch for them being great pets. They're active during the day, hunt prey, don't need much food or water, and tend to "hide" in silk cases they build along the top of their terrariums so you can always see them. They like to get water from inside flowers, and probably can differentiate between many colors, so adding bright flowers not only makes things prettier, it provides a watering hole and possible hunting advantage over color-blind insects trying to hide.

Of course, if you don't want to set up a terrarium and personally sentence crickets to death, just look at the screens in your windows. Odds are, a jumping spider is already living there and will stay as long as you let it. They're territorial.

Re: Newly discovered spider builds spring loaded snare to catch ants

#38

Post by optimalsolver »

pvaldes wrote: post #9
Foskya wrote: post #4

It is truly fascinating, I wonder how it evolved like that. Before becoming a spring as it is today how was it hunting in the past? What constraints made it need such a mechanism instead of a typical web?

Injured Himenoptera are known to send pheromones that trigger a vicious defensive response from other members of the colony. On a typical web the companion ants would do what the ants do. Go to war and flood the place surrounding the danger until eventually killing it. The spider does not have neither the stamina, nor the venom amount to deal with that. This web is designed to extract just one ant, while cutting the…

Of course, the problem with such a high amount of specialization is that if the green ant disappears, so does this spider.

Re: Newly discovered spider builds spring loaded snare to catch ants

#39

Post by imzadi »

spidercat wrote: post #34
NitpickLawyer wrote: post #24

Heh, for a second there this read like some of the Portiid adventures with Bianca and Fabian from Adrian Tchaikovsky's book "Children of time". If you find this kind of thing interesting and are a fan of sci-fi, I highly recommend the book.

Children of Time is one of the best books I've ever read, it's honestly amazing. It might be my all-time favorite. Seconding this recommendation!

I don't think I've been disappointed by anything from Adrian Tchaikovsky, tbh. Alien Clay and Service Model are also great.

Re: Newly discovered spider builds spring loaded snare to catch ants

#40

Post by enjrolas »

abrookewood wrote: post #22
enjrolas wrote: post #17

The part from the paper which is so interesting is why the ant bites the trap in the first place. The paper suggests that the spider puts out a pheromone that attracts the ant and triggers the ant to aggressively bite the snare, but the pheromone only does this for the spider's target species, the green tree ant . The researchers watched three other ant species check out the snare, go "meh", and move on, unharmed, wi…

Yeah, that is pretty crazy. I wonder what it smells like? Has to be an enemy specific to that ant species right?

that's a good question -- the paper describes it triggering aggression in the ant within milliseconds of it probing the snare with its antenna. I don't know the basis for it, but that's some down-to-the-metal ant programming right there
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