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Author Topic: Why do Spiders have 8 legs and Insects 6 daddy ?  (Read 11305 times)

Offline neilep

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Why do Spiders have 8 legs and Insects 6 daddy ?
« on: 29/04/2005 23:18:20 »
"Cos Spiders are greedy Son"...well that was my non witty retort to my son's question this evening....but, I reckon it's a good question and I said to him...." Well son, I'm not too sure but me knows a few squillion peeps in Internet land who might know the answer"

SO, Dear Wonderful People of Specialist Knowledge With Degrees and Stuff.

Why do Spids have 8 and Crawly things have 6 ?...Maybe there is no definitive answer here, perhaps I'll make do with your educated speculations !!..in any case

Your creepy-crawly-jump-up-and-shake-yourself-in-a-frenzy-to-get-rid-of-an-ant type of answer will be most welcome.

Ta....Neil


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Offline Ultima

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Re: Why do Spiders have 8 legs and Insects 6 daddy ?
« Reply #1 on: 30/04/2005 00:33:27 »
Ahhhh! i'm mega scared of spiders. But i've been online looking (sometimes through my hand) to see what peeps think about how arachnids evolved, the first fossils show up 430,000,000 years ago with scorpions. Check out the tree of life project http://tolweb.org/tree?group=Arthropoda&contgroup=Bilateria arachnids are types of arthropod. They are in a seperate branch away from insects 'n stuff, along with horse shoe crabs! So I guess they have eight legs because something before them had eight legs and it's still good for traction or something :D. Plus some spiders have adapted there extra legs to do clever things like jumping spiders have certain legs extended to act like springs, and some webby type spders make a net they wave aroound with special legs to catch flies.

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Offline neilep

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Re: Why do Spiders have 8 legs and Insects 6 daddy ?
« Reply #2 on: 30/04/2005 11:36:36 »
Well I luff spiders...always wanted a tarantula but for some strange reason wifey says 'No '(Little Britain mode) !!..however I do find it fascinating to take a gander at garden spiders building their beautiful webs and watching them catch lunch. I've seen those spiders waving their nets around to catch some grub, probably one of the Attenborough progs but all very  fascinating stuff.

Thanks for your response Matt and the link...nice !

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Offline Andrew K Fletcher

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Re: Why do Spiders have 8 legs and Insects 6 daddy ?
« Reply #3 on: 30/04/2005 13:36:51 »
Well in certain far-flung places around our fragile world, spiders are considered a delicacy. Now it might be a coincidence-who knows? But I noticed during the programme that one of the tribes had 8 members in each of its families. Could it be that they each prefer a leg to the rest of the spider?
 

Offline daveshorts

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Re: Why do Spiders have 8 legs and Insects 6 daddy ?
« Reply #4 on: 01/05/2005 01:37:51 »
I suppose having an extra pair of legs may be useful when walking on something with lots of holes in it like a web - as more legs can miss the web without you falling through.

Although I would guess web building was quite late in their evolution. Maybe 6 legs has an advantage over 8 in general as there are so many more insects than aracnids. I think 6 is the fewest legs you can have that allows you to walk quickly without falling over (you can have 3 legs on the ground allways) - so making an extra two is a waste of resources.
 

Offline neilep

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Re: Why do Spiders have 8 legs and Insects 6 daddy ?
« Reply #5 on: 01/05/2005 02:54:14 »
...and spiders legs grow back don't they ?....now that's pretty neat !!...and I bet they'd make good tap dancers too.

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Re: Why do Spiders have 8 legs and Insects 6 daddy ?
« Reply #5 on: 01/05/2005 02:54:14 »

 

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