Caterpillar is the larva stage of butterfly. Most caterpillars have cylindrical bodies consisting of multiple segments, with three pairs of true legs on the thorax and several pairs of short, fleshy prolegs on the abdomen. The head has six small eyes (stemmata) on each side that function in light detection but not in image formation. They have short segmented antennae and strong jaws.
Caterpillars have about 4,000 muscles as compared to human being who has only 629 muscles. Caterpillars might be that small but they have a powerful muscular contraction that aid their movement from the rear region.
As compared to humans, the caterpillar uses majority of its muscles for movement. There are fewer other insect that has more muscles than human. An example is grasshopper, it has about 900 muscles.
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