METAMORPHIC MIRACLES

Butterflies are blossoms with wings, visions of hope

Story and photos by Scot Stewart

A butterfly lights beside us like a sunbeam, and for a brief moment, its glory and beauty belong to our world… but then it flies again, and though we wish it could have stayed… we feel lucky to have seen it.
-  Author Unknown

The embodiment of change and freedom, butterflies honor the warm weather with their grace and beauty.  As delicate and fragile as they appear, they are remarkable, small animals, able to delight us with their floating flights overhead and their fluttering stops at brightly colored flowers as they add even more pizzazz to a colorful garden, field or woodland edge.
But these tiny (relative to most animals and plants) creatures, are a wonder in many other ways too. Some, like mourning cloaks and tortoiseshells, overwinter in the Upper Peninsula, where temperatures can drop to -35 degrees Fahrenheit. They do this by producing a type of antifreeze to survive the cold, only to surprise us on the first relatively warm day after most of the snow has melted with a flutter by.
The amazing migration of the monarch is relatively well-known. Monarchs start out as eggs in the U.P. and other northern edges of their range – essentially across Canada even with the north shore of Lake Superior (some maps include that part of Ontario, some don’t).  Adults in eastern Canada can fly up to 3,000 miles to wintering grounds in Mexico, before heading back north to the southern parts of the U.S. to begin the annual cycle of reproduction and slowly migrating northward again. Monarchs can travel 50 to 100 miles per day when following winds that aid their flights. The longest documented one-day flight was 265 miles.

 

The painted lady has an even more epic fall migration from parts of the High Arctic in Europe to northern Africa, a distance of 4,500 miles, with a return trip in the spring. They can fly 30 miles per hour at altitudes of 3,000 feet. They had gone relatively undetected in their mysterious flights until balloons fitted with nets were able to catch these small wonders recently on the trip south. American painted ladies also migrate betwen dry regions of northwestern Mexico in winter and a summer range throughout most of North America.
‘The number of butterflies worldwide is not certain. Many believe there are still many smaller butterflies in tropical areas yet unknown to science.  Estimates range from 18,000 to 25,000, a wide range in what is currently known and what may be. Around 725 butterfly species are known in North America, with 575 of them found in the lower 48 states. The worldwide numbers will face further challenges due to rapidly decreasing habitat destruction, reduction due to farming and development, and the effects of pesticides and genetically modified plants like corn on both larvae and adult butterflies.
Genetically modified plants are treated with herbicides that kill milkweed plants growing along the edges of farm fields where many monarchs lay their eggs. Research is still being conducted on the effects of pollen from modified corn on insects like monarch larvae.  Genetic additions of genes from bacteria are found in some strains of corn. The pollen from this corn may cause problems for larvae such as growth reduction or even death, although with research ongoing, the jury is still out on that issue.  The loss of milkweed plants, though, is undeniable.“

The caterpillar does all the work, but the butterfly gets all the publicity.”
– Attributed to George Carlin

They lead amazing lives following a four-step process called a complete metamorphosis Most people are familiar with the incredible changes butterflies pass through, starting with tiny eggs.  Barely visible, eggs range from 1-3 mm (about 1/16 to 1/8 of an inch) across. They range in color from white to yellow, beige to green. Painted ladies have bright turquoise ones. Pipevine swallowtails lay burgundy-colored eggs. Some butterflies lay a single egg at a time, like monarchs; others lay a cluster together in one place. A female monarch can lay up to 500 eggs.
Eggs hatch five to twelve days after being laid, becoming tiny larvae known more commonly as caterpillars. They have enormous appetites and are not much more than plant-eating bags. Most caterpillars eat leaves and other plant parts, so most eggs are laid directly on the food of choice and may feed exclusively one plant type, like monarchs on milkweed. For the monarchs, they can feed on many species of milkweed.  In the Upper Peninsula, common milkweed is the most familiar, but in wetlands and along the edges of lakes and ponds, they find the narrow leaves of swamp milkweed and, in flower gardens, orange blossomed butterfly milkweed.
Many species are plant-specific for their larvae’s food source.  Baltimore checkerspots prefer white turtlehead, a wetland species; pearly crescent checkerspot asters and a number of other checkerspots, like black-eyed susan.  A number of azure butterflies enjoy New Jersey tea, a rare shrub found in Keweenaw County. Common buckeyes like blue vervain; black swallowtails, golden alexander; viceroys and some moths, willows.  A number of skippers like grasses. Some species, like American painted ladies, are not so particular, choosing up to 200 different plants as hosts and allowing them to extend their ranges and be less reliant on single species.
Larvae use warning coloration to ward off predators or camouflaging coloration, like shades of green, to blend in with the vegetation or mimicry, looking like bird droppings or other objects to help them avoid predators.  Birds, other insects and some mammals are continually on the prowl for larvae.  Since most caterpillars lack any means of protection other than disguise or hiding, they have to do those things well.  Some swallowtail caterpillars can produce large horn-like structures or large eye spots to startle predators. Others can simply loosen their grip—they have six feet plus sets of pseudopods, false feet to hold on—and drop to the ground.
They do have soft outer skins they shed more than half a dozen times as they grow and are more vulnerable during these molts.  Their pliable skin also makes them vulnerable to parasitic flies and wasps.  These insects lay eggs on or slightly below the surface of the skin. The larvae of these insects feed on the muscles of caterpillars until they are ready to pupate into adults.  Ultimately, their feeding kills the butterfly larvae.
When a butterfly larvae is ready to pupate, it usually leaves the host plant and seeks a dry, sheltered place to attach the tip of its abdomen to a spot where it can hang suspended from a leaf, branch or other structure.  It again molts, and the new skin hardens into the chrysalis.  There it will remain for about two weeks before the mature butterfly emerges.  The plump body is full of fluids pumped into the veins of the wings, stretching them out before they dry.  Once that is done, the butterfly is ready for its first flight.

“Butterflies are self-propelled flowers.”  - R.H. Heinlein

Each butterfly species has a different pattern of color created by the arrangement of its scales. Scales are small shingle-like structures covering both the wings and body of butterflies and moths. Their bodies are constructed of a chitin exoskeleton. The patterns of species are very similar—close enough to create discussions and studies to determine if they are, in fact, different species or variations. There has also been confusion due to sexual dimorphism—different forms for each sex of the same species. There are advantages for males to be more visible, as they are generally more active than females and seek out them out, advertising their presence. Once females have mated, they spend most of their time laying eggs, when a less conspicuous appearance would be advantageous.
Even more amazing, individuals with  bilateral gynandromorphism show both male and female forms of the species, one on each side.  These individuals start as eggs hosting two sperm cells at fertilization.  One combines with the egg’s DNA in the nucleus of the egg cell to produce a female individual.  The other sperm cell  develops within the egg to produce male characteristics, resulting in butterflies with their right sides often looking remarkably different from the left sides.
Some butterflies also use their coloration or color patterns to warn predators they taste bad or are simply poisonous.  The monarch’s familiar story relates to the toxins found in milkweed sap.  Stored in the caterpillar’s body as it eats leaves, the toxins neither affect the monarch nor are lost in metamorphosis.  The butterflies are just as poisonous, and that fact is advertised in both the yellow-white-black stripes of the caterpillar (similar to the color markings of some bees and wasps) and the orange and black colors of the adults. Some birds, like orioles and grosbeaks, have developed a tolerance to the butterflies’ toxins and do eat small numbers of monarchs if they can find them. Pipevine swallowtail butterflies found in southern Michigan are also poisonous due to the toxins in the pipevine plants they eat.
The coloration and markings of these species have led to a number of cases of mimics—butterflies evolving similar colors or patterns to protect themselves from predators despite the fact that they have no toxins or bad taste for anyone trying to prey on them.  The monarch (which means queen or king) has a mimic called the viceroy (a stand-in for the queen or king).  The larvae feeds on willows and looks like a set of bird droppings.  The adult looks like a smaller version of a monarch with a sharp black vein curving through both of the bottom wings.  The pipevine’s marking are lest distinctive, it being mostly a bluish-black with reddish spots on the lower wings. This has led to red-spotted purples and some other swallowtails as mimics.

“Beautiful and graceful, varied and enchanting, small but approachable, butterflies lead you to the sunny side of life. And everyone deserves a little sunshine,” – Jeffrey Glassberg

Butterflies have no chewing mouth parts. Their feeding anatomy consists of a long, curled-up, tube-like tongue called a proboscis.  Used like a straw, they draw up nectar for energy, and the fluids of waste, like mammal droppings and decomposition fluids of dead animals, to obtain salts and minerals they cannot get from flowers. Small adult butterflies may live only a week or two before dying or becoming food for another animal.  Some can live ten months, surviving a cold winter or traveling thousands of miles.
Like birds, frogs, and other sensitive species, butterflies serve not only as beautiful puzzle pieces in the environmental jigsaw of our lives, telling us about the health of our surroundings and the completeness of our biome, but also as needed keystones in that puzzle.  As pollinators, they provide the mechanism for many plants to obtain the genetic variability they need to survive and adapt to our ever-changing world.  Their host-specific relationships are often as important to the plants they pollinate as the plants are as food supplies to growing larvae.
Butterflies are true wonders. They are tiny, beautiful insect pollinators, flashes of light airy flyers, and caterpillars giving hope to all about the wondrous changes life and growth can bring.

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