Floats Like a Butterfly
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The massive wing volume is far more than is needed to fly. However, the hind wings are not used for flight and removing them does not affect a butterfly’s ability to fly. Scientists theorize that the hind wings are merely for show, making the butterfly even more flashy. This seems counterintuitive in a world
Cabbage Whites have an uneven tumbling flight style and are often seen swirling in groups of three.
LENORA LARSON Butterfly Maven 10
September 2021 | kcgmag.com
filled with hungry predators. However, when a predator catches a butterfly and discovers that the promise of a huge meal is a sham it may have learned that it’s not worth the energy to hunt them. Most predators consider the wings inedible and remove them before gulping down the diminutive body.
Summary Butterflies have an amazing array of flight capabilities. They are among the fastest flying insects but can also hover, glide or fly slowly. They fly in short sprints or perform marathons of thousands of miles. Butterflies rival dragonflies and hawk moths in their abilities; however, all must bow to the humble housefly as the true master of flight. Photo by Lenora Larson.
The Mechanics of Flight Think of butterfly wings as sails that are flapped by the thorax muscles rather than actively flapping wings like bats and birds. Slowmotion photography demonstrates that when the thorax muscle contracts, the “four sails” are contorted into a figure eight pattern. When the muscle relaxes, the wings are pushed upward and forward by released air and the butterfly is propelled forward. Butterfly wings are proportionally huge with a much larger ratio of wing volume to body mass than any other flying insect. All four wings function as giant rudders, which allows for quick, sharp turns. Monarchs can make a 90 degree turn in less than one body length.
Powerful thoracic muscles produce a butterfly’s flapping motion of flight, unlike birds that flap their wings to fly.
Flight Styles Experienced butterfly watchers can often identify a butterfly at a great distance because of its flight style. For instance, members of the Brushfoot Family like Red Admirals, Painted Ladies, Fritillaries and Monarchs elegantly flap and glide, but at different speeds and heights. Swallowtails flap their wings more energetically with a shortened glide period. They also may characteristically flutter and half-hover as they nectar. Skippers flap their wings very quickly and some species even produce a whirring sound. Poisonous butterflies do not need ultimate maneuverability and fly more directly as seen in the Pipevine Swallowtail, the most poisonous butterfly in North America. It rarely glides and has been dubbed the “Bat Butterfly” because its rapidly flapping wing movement resembles a bat. Anatomical differences in wing shape and attachment probably account for the different styles of flying.
Photo by Betsy Betros.
An Anatomy Lesson Like all insects, the butterfly’s body is divided into three segments, which have specific functions. The head is in charge of coordinating, seeing and eating. The middle section, the thorax, is equipped with powerful muscles that drive all locomotion by leg and by wing. The abdomen holds the organs for digestion and procreation. Like all insects, the wings consist of two thin membranes of chitin, a protein related to our fingernails and hair. Insect wings have no nerves or blood supply, so they do not feel pain or bleed. The so-called veins are hollow air tubes, which the butterfly pumps full of air shortly after emerging from its chrysalis.
Photo by Lenora Larson.
utterflies seem to float aimlessly across your garden, but this flight pattern is suprisingly purposeful. Its unique design confounds predators, which are unable to predict the butterfly’s position and plan their attack. Compare this gentle maneuvering with birds which flap their wings up and down in order to move directly forward, making them an easy target for raptors.
Three Giant Swallowtails demonstrate flight movements including the flutter-hover when nectaring.
A Marais des Cygnes Master Gardener, Lenora is a member of the Idalia Butterfly Society and Kansas Native Plant Society. She gardens in the clay soil and cruel winds of Paola, KS. She may be contacted at lenora.longlips@gmail.com.
