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    So getting stuff for uni from under my bed and there were like 5 dead spiders, and just got me thinking why are they always dead on their back with legs kind closed.
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    I think a dissection is required here doc. :yy:

    Report back with your findings.
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    ******* repped for this question, love it.
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    Holy mother of ****, ill have to rep tomorrow
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    that's a damn good question
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    hmm, could it be that when they die their legs naturally curl inwards. now they have a big body above the legs leading to them toppling over!
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    Nobel price, here I come!
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    Some believe it's because they are renouncing their faith to Satan and declaring it to God instead.

    Others believe it can be explained otherwise. They would be wrong.
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    After a quick google.. apparantly

    'They're basically hydraulic. Their natural state is curled up, and if I recall correctly pressure is exerted on a fluid to make them extend. When they die, the pressure is no longer exerted and they curl up.'

    'Muscles attached on the inside of the exoskeleton contract to move the legs inward, but spiders don't have any muscles to extend the legs back out again. Instead, they have to force bodily fluids (mainly blood) into the legs to push them outward. If a spider loses too much body water, it can't generate the necessary hydraulic pressure to push its legs out. This is why you sometimes see spiders on their backs with their legs curled up.'
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    They don't, they've actually died the right way up but just before they die there is an agonising process in which each leg painfully snaps upwards and curls back above its body, one leg after another. This gives the illusion that it's on its back.

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    Just kidding, I have no idea
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    They dont die on their backs if you squish em real good.
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    (Original post by princessnavi22)
    After a quick google.. apparantly

    'They're basically hydraulic. Their natural state is curled up, and if I recall correctly pressure is exerted on a fluid to make them extend. When they die, the pressure is no longer exerted and they curl up.'

    'Muscles attached on the inside of the exoskeleton contract to move the legs inward, but spiders don't have any muscles to extend the legs back out again. Instead, they have to force bodily fluids (mainly blood) into the legs to push them outward. If a spider loses too much body water, it can't generate the necessary hydraulic pressure to push its legs out. This is why you sometimes see spiders on their backs with their legs curled up.'

    This is correct. Haemolymph pressure is responsible for limb extension in aranea. Upon death this pressure is relaxed, tensor muscles the curl the legs together which results in a form which is most stable on it's back. The haemolymph will quickly drain and evaporate - significantly reducing the mass of a dead individual which will in turn make it easier for the carcass to adopt its upturned position.
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    Because they are dramatic little ****s.
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    (Original post by princessnavi22)
    After a quick google.. apparantly

    'They're basically hydraulic. Their natural state is curled up, and if I recall correctly pressure is exerted on a fluid to make them extend. When they die, the pressure is no longer exerted and they curl up.'

    'Muscles attached on the inside of the exoskeleton contract to move the legs inward, but spiders don't have any muscles to extend the legs back out again. Instead, they have to force bodily fluids (mainly blood) into the legs to push them outward. If a spider loses too much body water, it can't generate the necessary hydraulic pressure to push its legs out. This is why you sometimes see spiders on their backs with their legs curled up.'
    You learn something every day. Thank you!
 
 
 
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