An online resource based on the award-winning nature guide

Incomplete Metamorphosis

Grasshoppers Molting

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Molting is the process by which insects and other arthropods grow. They have an external skeleton (exoskeleton) that supports and protects their body, unlike the internal skeleton of most other animals. Since the exoskeleton is hard and its outer layer is non-living, it cannot grow bigger by small increments as the human skeleton does. As an insect increases in size, it sheds the inelastic exoskeleton on the outside of its body, and replaces it with a larger, soft exoskeleton that has formed underneath the smaller, shed exoskeleton. Eventually this new exoskeleton hardens. This process is repeated several times during the life span of an insect (the exact number depends on the species).

Grasshoppers experience incomplete metamorphosis: they go through three stages in their life cycle – egg, nymph and adult. Nymphs are miniature versions of adult grasshoppers, except that they are usually light in color and do not possess functioning wings. Nymphs undergo five or six molts and with each molt their size increases and their wing pads progressively develop. Usually within a month nymphs molt for a final time, emerging as adults with fully developed wings. (Photo: shed grasshopper nymphal skin showing small, developing wing pads; inset – fully mature grasshopper)

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Damselflies Hunting

6-12-13 damselfly eating prey2 147Damselflies, nature’s more delicate version of a dragonfly, spend most of their life underwater, first as an egg and then as a nymph. Eventually, after a year or so, they crawl out of the water onto nearby vegetation, shed their nymphal skin for the final time and emerge as winged adults. A damselfly’s beauty belies its behavior — most damselflies are voracious predators, both as aquatic nymphs as well as adults. In flight, they hold their bristly hind legs in a basket shape to scoop up their prey. The prey is then transferred to their front legs, which hold it while the damselfly devours it.