Monthly Archives: June 2010

Trust Me When I Say You’re Going to Need a Blow Torch and Some Rope, Amaurobius ferox Spiderlings.

black-lace weaver spider

In a discovery both sinister and intriguing, a biologist in South Korea has found that life as a juvenile Black-lace weaver spider (Amaurobius ferox) is far from easy. As part of a group known as subsocial spiders, an A. ferox individual will hatch with some 60-130 siblings and remain on a communal web with its mother, living off the eggs she lays for it until it is old enough for a more solitary lifestyle. But things aren’t as simple as they sound, because before they can venture off on their own, these spiderlings must first eat their devoted mother alive. A week or so after hatching, the mother will encourage her brood to devour her body, a strategy which has been found to produce a higher number of surviving offspring, as opposed to abandoning them early to lay a second clutch.

But this is not the only cooperative behaviour displayed by A. ferox juveniles. In the first study examining the synchronisation movements in non-social or subsocial spiders, Dr. Kil Won Kim of the University of Incheon of the Republic of Korea has found that in response to certain stimuli, the orphaned spiderlings will group together and contract their bodies in unison in order to make their web pulse. This behaviour, which would emerge just one day post-matriphagy, is typically triggered by the approach of intruding insects, mites or worms, an individual spiderling sensing this potential threat, causing it to contract in response. Other spiderlings in the huddle then follow suit, contracting and relaxing their bodies to create a pull-and-release effect on the web. The A. ferox juveniles continue to use this apparent defense mechanism for seven to nine days, by which time they appear to grow out of it, focussing their collective efforts on hunting prey up to twenty times their size instead. Dr. Kim notes, “contraction seems to occur only during the period when the other is not present any more but the young are not yet capable of capturing prey.”

You’ll have to visit the BBC report to see clips of the A. ferox matriphagy and web-pulsing, but here are some Yellow sac spiderlings doing the former:

So alright, spiders. I was willing to turn a blind eye to the fact that you enjoy decorating your webs with rotting insect corpses because you like having freeloaders come and squat in your home. I just figured you were lonely and/or needed someone to verse you in Sonic Racing or something. And I don’t really have a problem with your lady jumping spiders beating each other to death at the drop of a hat, because let’s face it – girls will be girls, amirite? But this is just taking it too far, even by your atrociously low standards.

I mean, how does it work exactly? You’re all sitting around the dinner table like, “Hey Mum, look how many eggs I can fit in my mouth,” and “Do you think Justin Bieber like spiders? I bet he does. He seems nice. Do you think he’s nice? I wonder what he’s having for dinner. I bet it tastes better than these eggs,” when suddenly your mum’s like, “So… who wants part of my abdomen for dessert?”

And you’ll be all, “Wtf, Mum!”

And she’ll be like, “Watch your language.”

And then one of you will be like, “But Mum…” and, “Does this mean I’m going to have to catch the bus to school now?”

And she’ll be all, “Gregory, don’t start. Now excuse yourself from the table and come over here and eat your mother.”

So you’ll reluctantly slink off your chairs and edge towards her, telling each other that you’ll probably be grounded either way, but she’s much less likely to enforce it if you eat her first, and pretty soon she’ll be engulfed. Someone will point out rather sheepishly that it actually doesn’t taste that bad, and before you know it, you’ll be collectively digesting your mum in front of Wizards of Waverly Place.

But then what? What’s a family of inexperienced orphans going to do with no food and no protection from strangers who wouldn’t mind devouring and digesting you in front of the television? I’m sorry to break the news, spiders, but huddling together on your web, contracting nervously in unison, muttering, “Oh my God, oh my God, oh my God, we’re all gonna die, we’re all gonna die, we’re all gonna die,” isn’t going to solve your problems once the insects and worms figure out what’s really going on.

Guys, you need a more sophisticated plan. And that’s where I come in. But first you’ll need:

* A precocious attitude
* An empty house, preferably in the initial stages of being renovated
* Paint tins
* Rope
* Bricks
* A blow torch
* Staple guns
* Live electrical wires lying in a pool of- –

What? Too complicated? Oh for Christ’s sake, spiders, I was only trying to help. GOD.

Original paper published by Insects Sociaux // Picture from Avec La Vie.

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Related posts: Assassin Bug, What Do You Mean You’ve Never Seen The Jackal?

Way to be a Vegetarian for all the Wrong Reasons, Bagheera Kiplingi

– bec

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