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MACROSCOPE

Wilderness

Thomas Eisner

Dressing to Disappear

Last summer I had the good fortune of spotting a little caterpillar at the site, an insect that is really quite common in our area but is known to few because it is so spectacularly adept at achieving invisibility. The caterpillar escapes detection as it frequents various flowers because it dresses up as a flower. It cuts pieces of petals from flowers and fastens them onto its back with strands of silk that it secretes from special glands, thereby succeeding in entirely covering itself. I found the caterpillar, which goes by the elegant name of Synchlora aerata, on flowers of the common fleabane, Erigeron strigosus, one of several composite plants that had gained a foothold in the patch.

Figure 3. <em>Synchlora </em>caterpillarClick to Enlarge Image

Synchlora is beautifully adapted to perform its vanishing act. It has tiny bundles of spines protruding from its back, to which it fastens the silk it uses to tie down the petal pieces. It appears able to sense when the pieces need renewing. Because the larva carries no vase on its back, the pieces wilt with time. The larva renews them at intervals, ensuring that its protective cover remains fresh and appropriately floral in appearance.

When the larva pupates it crawls from the flowers to a more central location on the plant. There it eventually spins a loose cocoon. It weaves its petal cover into the fabric of the cocoon, and as a consequence blends in beautifully with the background. The delicate moth that emerges from the cocoon is a pale yellowish-green.

Everyone should have a patch of wilderness within easy reach. Gardeners should give serious thought to whether they might wish to let a portion of their garden revert to wilderness. I am not calling for the replacement of the ornamental garden. Just for the incorporation of a patch of wilderness into what we now devote solely, with justifiable enthusiasm, to the display of magnificence. The patch could introduce a magnificence of its own—the magnificence of reality, played out at close range, within visual access, and to the immense benefit of the observer. The patch would require neither weeding nor insecticidal treatment. The insects, in fact, would be part of the show. There would be no price of admission, or predetermined performance times. Just entertainment and the opportunity to wonder....








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