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Old 08-29-2002, 11:29 PM
chuckster chuckster is offline
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How many legs has a centipede/millipede?

You would think the answers would be obvious, 100 and 1000 respectively. But it would be amazing if the number of legs on these animals were powers of ten exactly. Has anybody ever actually Counted the number of legs on a centipede or millipede to make sure they do indeed have 100 and 1000 exactly, or does everyone do like I do and simply Assume the numbers of legs to be 100 and 1000 respectively? And, do different species of these creatures have different numbers of legs? If there are any experts on these creatures out there, I would certainly like to know.
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Old 08-30-2002, 12:05 AM
Richard Pearse Richard Pearse is offline
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While I look for a site I'll mention that I'm pretty sure that the name Centipede and Millipede hugely exagerates the number of legs on the respective creatures.

Ok, from Encyclopedia Encarta:

Quote:
The centipede body is divided into well-marked segments, the number of which varies from 12 to more than 100. The head, which is covered by a flat shield above, bears a pair of antennae, usually of considerable length and consisting of from 12 to more than 100 joints; a pair of small, strong, toothed, and bristly mandibles; and a pair of underjaws, usually with palps. The next, limblike appendages are followed by a modified pair of legs with strong joints, terminating in a sharp claw into which a poison gland opens. These appendages are used for seizing and killing prey. The two legs on each other segment are usually seven-jointed, sometimes bearing spurs and glands, and are generally clawed.
It's not entirely clear but my interpretation of the bolded portion is that there is one pair of legs on every second segment. So given an insect of over 100 segments as mentioned earlier, there would be a bit over 50 legs. Only just over half the number its name would have you believe and that is for the larger ones.

Quote:
Millipede, any of about 1000 species of cylindrical, many-legged arthropods (see Arthropod). Found worldwide, millipedes have segmented bodies with two pairs of legs on each of the 9 to 100 or more abdominal segments, depending on the species, and one pair on three of the four thoracic segments.
The only thing close to 1000 here is the number of species. Assuming a large over 100 segmented insect, you would still only have 400-500 legs.
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Old 08-30-2002, 03:33 AM
barbitu8 barbitu8 is offline
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Quote:
Originally posted by Skogcat
It's not entirely clear but my interpretation of the bolded portion is that there is one pair of legs on every second segment. So given an insect of over 100 segments as mentioned earlier, there would be a bit over 50 legs. Only just over half the number its name would have you believe and that is for the larger ones.
All insects have six legs; hence these are not insects. In addition, all insects have three body segments. Note, that spiders, having two body segments and eight legs, are also not insects. (They are arthropods.) The number of legs on centipedes vary, but it is not exactly 100.
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Old 08-30-2002, 04:19 AM
Darwin's Finch Darwin's Finch is offline
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Centipedes have one pair of legs per trunk segment; millipedes, for the most part, have two (see below). For centipedes, the number of trunk segments can vary from as few as 15 to as high as 191 (see here). The number of leg-pairs in centipedes is always odd (see previous, as well as here and here).

Millipedes can have even-numbers of segments (the first segment has no legs, the second and third have one pair of legs each; all other segments have two pairs [except in the Colobgnaths, which also have only one pair on the 4th segment]). From here, the millipede with the most legs, Illacme plenipes, has about 750; most average between 100 and 300.
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Old 08-30-2002, 05:27 AM
Mangetout Mangetout is offline
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Quote:
Originally posted by Skogcat
It's not entirely clear but my interpretation of the bolded portion is that there is one pair of legs on every second segment. So given an insect of over 100 segments as mentioned earlier, there would be a bit over 50 legs. Only just over half the number its name would have you believe and that is for the larger ones.
I thought there was a pair of legs on every segment except the first few (rather than 'other' meaning alternate segments); in any case, you have miscalculated; 100 segments with a pair of legs on alternate segments would be 100 legs.
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Old 08-30-2002, 11:05 AM
Richard Pearse Richard Pearse is offline
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Ah yes to the miscalculation, and of course they're not insects, any idiot knows insects are the 6 legged ones. It was late and I was tired
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