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Why do spiders dangle a leaf from their webs?

  1. Oct 11, 2011 #1

    DaveC426913

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    Why do spiders dangle a leaf from their webs? (we call them Christmas ornaments or toys)

    I have seen too many spider webs with a leaf dangling from it to be chance. I've even seen one spider dangling a candy bar wrapper (what's he trying to lure??)

    I know there's lots of plausible explanations (trying to cut it out of its web, built their web accidentally attaching it to something moveable), but does any one actually know?
     
    Last edited by a moderator: Oct 19, 2011
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  3. Oct 11, 2011 #2

    bobze

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    Re: spider webs

    I don't know Dave. I have lots of spider webs on my front porch full of leaves, but I honestly think this is just from the trees in the front yard loosing their leaves.

    You say you think its to many to be due to chance, but do you notice these webs with leaves in early spring? I can't recall if I do. Seems like its a "fall" spider web thing, which leads me to suspect that the leaves accidentally get hung up in there and those webs are so darn tough and strong.

    Maybe take some photos now and compare them to spring time to see? Would be an interesting little experiment.

    I do know that some species of spider like those "wolf" types that build little webs and holes in the ground will camouflage their web network, but I don't know that I've ever heard of the "orby" types doing anything like this.

    I have an entomology acquaintance that works specifically with spiders. I'll ask next time I bump into him if there is anything more to it.
     
  4. Oct 14, 2011 #3
  5. Oct 14, 2011 #4

    Monique

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  6. Oct 14, 2011 #5

    DaveC426913

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  7. Oct 19, 2011 #6
    Re: spider webs

    There must be more to spiders than meets the eye. They are evolving at a much greater speed than otherr inscects. For example the spider that now inhabits any car wing mirror. Not only has it found a location that enables it to take its web overground at speed sifting out its prey, which is a pretty damn fine achievement, but it has mastered an understanding of automobile design by attaching the web to the parts of the car that remain static and unaffected by the owners entry to the vehicle and adjustment of the mirror. It has also learned where to locate itself for safety so that it is unaffected by the car-wash aside from having to spin a new web afterwards. This is a highly specialised inscect that has evolved in direct corelation to motor vehicle developement. What did it do before the motor car? Think about the huge advance made in such a short time.

    Spiders have learned to understand the mechanics of human created structures such that they are able to fully take advantage of our own forward progression and are seemingly learning as we learn. I currently have a spider with a web on my back door that has ingeniously been created in an arch shape. How did that spider know that it had to dothat in order to preserve its web? How long did he spend observing human activity before deciding how to construct this web. It was not a process of trial and error, the web was an arch design from the outset. Spooky.
     
    Last edited: Oct 19, 2011
  8. Oct 19, 2011 #7

    Ryan_m_b

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    Re: spider webs

    I think it is more appropriate to say that human artefacts provide good environments for normal spider behaviour. They don't observe and plan to the best of our knowledge. When a spider builds a web it simply tries to make one from whatever point. Things like car mirrors and unused ladders make good environments for webs because they are unlikely to be broken and can catch insects.
     
  9. Oct 19, 2011 #8

    DaveC426913

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    Re: spider webs

    I think he's kidding around...

    ...mastered an understanding of automobile design...

    ...How long did he spend observing human activity...
     
  10. Oct 21, 2011 #9

    Pythagorean

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    Googling I saw suggestions that spiders use plum bobs during construction to make sections of the web taut. Perhaps in the fall, leaves make ready plum bobs?
     
  11. Oct 21, 2011 #10

    DaveC426913

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    I would be interested in reading about that. It aligns with my hypothesis that a weighted, hanging object is as good an anchor as a fixed point.
     
  12. Oct 21, 2011 #11
    And how do spiders find their way ? in my garden spiders build webs from one shrub to another which are 6-8 feet away from each other and i have not seen many insects being caught only dried leaves and other crap.
     
  13. Oct 21, 2011 #12

    DaveC426913

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    1] Spiders have excellent vision.
    2] Their web-building programming leads them to climb, attach, drop, climb, attach.

    That's because they eat the insects. :wink:

    It goes further. They repair their webs after catching and eating an insect. They don't necessarily need to repair their web every time some flotsam gets caught in it.
     
  14. Oct 21, 2011 #13

    Monique

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    Let's go for 3]:
    They wait for wind to pick up, at the moment that they feel a breeze they will make a long thread and let it carry away. At the moment the line is taut they will cross it like a trapeze artist and venture into unexplored territories :smile:
     
  15. Oct 21, 2011 #14

    lisab

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    I've heard that too, and a web build that way has the added advantage of being in a known breezy area, which gives it a better chance of snagging prey.
     
  16. Oct 28, 2011 #15
    Since this post has had a couple more replies, and someone noted that spiders adapt quickly to whatever surroundings there being tossed into, I thought i'd show you guys a picture proving this point up to a certain degree!

    This is sadly not an answer to the original poster, but still worthy of a glance!
    Check out the picture!

    This is is a picture of trees if I recall somewhere on the shores of Pakistan where there has been floods. What the article said, and sorry I do not have any link as I just kept the picture, but spiders have taken refugee in trees to survive the floods, and since this has happened, the number of mosquitos around the area has dramatically lowered and people getting malaria as well! Quite interesting and pretty special to see nature at work!
     

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  17. Oct 28, 2011 #16

    Evo

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  18. Oct 29, 2011 #17

    DaveC426913

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    Huh. I would have bet money those aren't spiders at all, but tent caterpillars.

    http://www.popsci.com/science/article/2011-05/spiders-fleeing-pakistans-floodwater-take-trees" [Broken].
     
    Last edited by a moderator: May 5, 2017
  19. Oct 29, 2011 #18

    Pythagorean

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    I wonder what spider social behavior is like when they're forced into tight colonies...

    Is this mostly all progeny of a spider that laid eggs, who's offspring knew not to jump or is this just some statistical result of the trees being the only ones around to catch drifters?

    I've always thought of spiders as loners.
     
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