Young
Naturalists
Damsels andDragons
BY JANICE WELSH
ragonflies and damselflies are the D helicopters of the insect world. With their bulging eyes, long tails, and tapered wings, they look like helicopters. In fact, they maneuver like BRENT FLINT Most dragonflies measure 1 to 3 inches across their helicopters too. They can fly backwards and wings. One Australian species has a 7-inch wing- change direction in just one body length of air span. About 250 million years ago, one kind of space. They can glide, hover in midair, and make
dragonfly had a wingspan of 30 inches. ILLUSTRATION BY DAVID AMDUR sharp turns. Some can fly up to 35 miles per hour.
32 T HE MINNESOTAVOLUNTEER JULY–AUGUST1996 33 EUGENE F. O’NEILL BRUCE EDINGER ALLEN BLAKE SHELDON Dragonfly Design Try sneaking up on a damselfly or dragonfly and you will find Like all insects, damselflies and dragonflies have six legs, two pairs out how well it sees! Its bulging of wings, two antennae, and three body parts—head, thorax, and eyes detect the slightest abdomen. They wear their skeletons on the outside of their bodies. movement. Dragonflies and This tough outer covering is called an exoskeleton. damselflies look scary, but they do not bite or sting. DOMINIQUE BRAUD Dragonflies and damselflies live in and near ponds, streams, and Dragonflies (top two photos) rest with lakes. Of 5,500 species of dragonflies worldwide, 86 are known to wings open. The closely related damselfly live in Minnesota. Minnesota counties with the most known Janice Welsh runs Project (bottom) folds its wings together. Dragon- species of dragonflies are Anoka, Washington, Pine, Lake, WILD, a DNR program flies look stronger than damselflies and fly Clearwater, and Cook. for schools. faster with more rapid wingbeats.
34HE MINNESOTA T VOLUNTEER JULY–AUGUST1996 35 The dragonfly bends its legs to form 5 a basket to catch food—mosquitoes, black flies, gnats. Large dragonflies even eat bees and beetles.
6 4 Mighty Morphin’ A dragonfly’s life begins as an water (3) onto a plant, rock, or 7 egg laid underwater (1). The log and molts one last time. Its egg hatches into a nymph. The abdomen inflates (4) and blood nymph eats tadpoles and flows into its wings, which nymphs for two years. While minnows (2). The growing slowly unfold, dry, and stiffen. flying, the male (5) fertilizes the nymph molts its exoskeleton, This transformation from egg to eggs of the female (6). The male just as a snake sheds its skin. adult is called metamorphosis. holds onto the female (7) as she The nymph crawls out of the These creatures may live as 3 deposits her eggs in the water. ILLUSTRATION BY VERA MING WONG I
The nymph’s lower jaw unhinges and 2 slides out like a big drawer to grab a tadpole or minnow. Minnesota’s Biggest Insect Collector Look for damselflies The University of Minnesota near wetlands, ponds, Insect Collection has about rivers, and lakes. 2,865,000 insect specimens, representing 43,000 species found in the United States and many other parts of the world. The collection started in 1897 with insects and spiders from the North Shore of Lake Superior. Current staff members have made
expeditions to collect insects in ALLEN BLAKE SHELDON Costa Rica, Ecuador, Peru, A Naturalist’s Eye for Dragons French Guiana, and Trinidad, State park naturalist Mark came to live in the restored making this one of North Carroll has been interested in wetlands. Mark made maps to America’s major collections. RICHARD HAMILTON SMITH dragonflies and other insects show other researchers where University research and Dragonflies are also called since he was a kid. In the clover different dragonfly species live teaching programs use the darners, darning needles, biddies, fields near his house, Mark and in Minnesota. collection. For information, horse stingers, and bee hawks for his friends had contests to see Mark earned a bachelor’s call 612-624-1254. their ability to catch bees in midair. who could get the most degree in earth sciences and a bumblebees into a jar. Mark’s master’s in biology, then joined mother made him a butterfly net the Department of Natural and turned old shoe boxes into Resources as a naturalist. YES: Young Entomologists’ Society storage containers for his At Sibley State Park in west- People who study insects are called entomologists. The Young collections. On the kitchen table, central Minnesota where he Entomologists’ Society is a non-profit group that helps young people study he raised monarch butterflies. works, Mark has counted more insects. For membership information, contact YES, 1915 Peggy Place, As a student at St. Cloud than a dozen species of Lansing, MI 48910-2553; 517-887-0499; e-mail [email protected]. State University, Mark studied dragonflies. This July he will Also available from YES is Creepy Crawlies and the Scientific Method by all kinds of wildlife. He worked show dragonfly slides and take Sally Stenhouse Kneidel. This book for teachers tells how to study pond on a study of restored wetlands park visitors on a hike to see ecology in the classroom. The book describes more than 100 hands-on —ones that people drained of what he calls “dragons in the experiments for children. water and later fixed to hold air.” To find out more, call the water again. He wanted to see DNR Information Center (see how quickly aquatic insects page 59).
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