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Catapulting spider winds up web to launch itself at prey (phys.org)
45 points by dnetesn 4 days ago | hide | past | web | favorite | 18 comments

Thank you! Here's the same video, but starting a few seconds before the "catapulting" https://youtu.be/XiP2IcE-c5A?t=60

"Catapulting" seems like the wrong word.

The mechanism is described as:

> When the spider releases the web, both spider and web accelerate forward very rapidly. The rapidly moving web tangles around the prey insect, starting the capture process from a distance.

But this process starts when the prey is already in the web.

Yeah, watching the video, it doesn't seem like catapulting at all. Entangling feels more accurate.

> Just when you thought spiders couldn't get any more terrifying.

Why do we have to go for the same tropes again and again ? You're writing a science-dissemination article, is it really necessary to portray spiders as 'terrifying' ? They could have said "cool", "weird", "unique", "alien", i don't know i'm not the one getting paid to write stuff.

But no, let's write this as if we're talking to middle-schoolers, ooooh scary spiders !!!!!!

In articles like these, I get the impression that the only substance is what is quoted or paraphrased from the actual article being talked about, and the job of the quoting author is to simply pump these out at a moderate speed, with added filler. The filler doesn't actually matter: it's just calming background noise for the actual content being "disseminated". If you were just provided quotes from the paper and illustrations, you'd feel like you're talking to a robot's notebook. The intended effect seems to be a minimally intellectual, maximally effortless, elevator-type anecdote-conversation. If you're making small talk with someone you hardly know on the elevator, you wouldn't care to criticize their viewpoints, right? I guess this is a long-winded way of describing click-bait.

Genuine question are you afraid of spiders? Am I correct guessing from your response here that’s a “no”?

That's irrelevant, it's an article on phys.org and is expected not to be written like this.

That's perfectly fair, should I have not asked about the commenter's own personal relationship with arachnids, or was I otherwise wrong to infer that they may have something to share about why people (like me) fear them? If so, why?

I used to keep tarantulas as pets and went on to study biology

Oh excellent! What was the most interesting thing you went on to learn about arachnids as a pet owner?

Lots of little details.. Do you know how tarantulas mate?

When a male has his ultimate (final) molt and reaches sexual maturity he is a completely different spider. During this ultimate molting process he obtained his sexual organs, which are bulbs (emboli, plural; embolus, singular) on the end of his pedipalps that are used to transfer sperm from his sperm web to the female. In many species males also have tibial spurs, which are "mating hooks" on the underside of the tibia (or long segment) of the first pair of walking legs and are used to engage the female's fangs during mating. taken from here: http://www.tarantulas.com/sexing.html

So the males dig a little hole, lay a sheet of silk over it and deposit their sperm in this little 'bowl'. Then they suck it up in what is effectively syringes that are developed at the end of their pedipalps. They use those to transfer the sperm to the female

Do you know how tarantulas mate?

I know what they look like, but--as alluded to in another comment, I have a touch of the fear of spiders due to a horrifying experience playing in the woods as a kid.

The hilarious paradox here is that I find them incredibly interesting creatures to read and learn about. Just not look at.

So the males dig a little hole, lay a sheet of silk over it and deposit their sperm in this little 'bowl'.

Is this a reproductive process that's unique to tarantulas (in the arachnid kingdom, that is), this sort of "prepping" of the sperm before transferring to the female spider? I would guess it has to be based on what I recall--please give me the correction if I'm wrong-but most web dwelling spiders lay their eggs in webs, the tarantula likes dirt and soil, so their reproductive workflow demands a "dirtier" method? Sorry for the pun.

Good question, i think all spiders also do this (tarantulas are not technically spiders themselves), but scorpions do it differently. Scorpions lay a small.... it looks like a mucus dildo, they call it a spermatophore.... on the ground and then guide the female over it during a sort of mating-dancing ritual.

Yeah I understand that a lot of people get the creeps with spiders. I remember a friend back in highschool telling me "it's the way they walk, it creeps me out"

But what's also true is that everyone ended up being curious about my tarantulas and would spend a few minutes checking them out, even if their first reaction to the concept of me having pet tarantulas was disgust or fear.

I wonder to what degree arachnophobia (even mild) is a product of society. This article is a good example, if even when someone is about to tell you something new and interesting about spiders they call them terrifying, of course most people will internalize this.

(tarantulas are not technically spiders themselves)

This is something I've heard once before, but the specifics of why elude me--a refresher if you'd be kind enough to indulge my curiosity further? (There's a reason below) I've also heard that their bodies are quite fragile, or specifically their 'exoskeleton' is incredibly fragile but they've got strong muscles?

if even when someone is about to tell you something new and interesting about spiders they call them terrifying, of course most people will internalize this.

This is what clued me in that you may have some opinion and interesting things to share, just the way you responded to it.

For context, despite my fear of spiders, I was once in a relationship with someone who had not one, not two, but THREE pet spiders--and had many friends who were also similarly enthusiastic arachnophiles. She loved the creatures and came to help me appreciate them a bit more and even taught me a few things about them, despite my own fears, but I learned to recognize just the way one reacts to the discussions of spiders.

So that's why I started this discussion off inquiring the way I did--that you seemed like someone who didn't have much fear of the creature.

Thanks so much for sharing your knowledge here today!

So i looked it up and from what i see Mygalomorphae (which is tarantulas, trap-door spiders and others) are an infraorder of spiders. I don't know why I remember the difference to be more distinct.

In any case, the way i mentioned it is as a technicality (like tomato is a fruit). mygalomorphs are slightly different than other spiders, a bit like ""ancient"" spiders. They have two pairs of book lungs (breathing organs), and their fangs are parallel and face down (in spiders the fangs face eachother i think)

Glad i could share ^_^

I had this feeling the entire time I was reading Children of Time, which is some excellent hard sci-fi about portia spiders that hyper-evolved into sentient beings.

The explanations of things in the book were absolutely fascinating, but then I'd try to visualize, and the more I did that the more revolted I got. Such cognitive dissonance. And now I'm psyched for the sequel that just dropped yesterday.

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