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Butterflies . . . there are anywhere from four million to 40 million species of insects . . . Insects have been roaming the planet for around 400 million years—that’s about 395 million more years than humans. That kind of staying power requires good adaptations, the ability to quickly evolve to deal with environmental changes, and a considerable diversity of species. Biologists estimate that there are anywhere from four million to 40 million species of insects—up to a quarter of a million species of beetles alone. Insects dominate the forest in terms of sheer numbers, sometimes much to our chagrin. Insects have their skeletons on the outside for protection against predators and dehydration. The ability to fly allows them to escape quickly and to find food and new habitats. They reproduce very quickly, therefore, evolve and adapt to environmental changes very quickly, too. A variety of adaptations such as camouflage, teamwork, mimicry, and stinging help the insects maintain their enormous numbers. Of special interest are the butterflies, the showiest insects without a doubt. You will see them on any summer stroll along the Four Soldiers Path or around the Pond of Safety. As insects, they go through complete metamorphosis in four life stages: egg, larva (the caterpillar), pupa (chrysalis), and adult (the butterfly). Adult butterflies appear when the air temperature is above 60 degrees, spring through fall. Various adult butterfly behaviors give you insight into their daily life needs, include the following: Nectaring – Adult butterflies take nectar from plants. They have sensors for smell and taste in various places on their body, but most smell with their antennae or forelegs. Special receptors in their feet detect sweet liquids, causing the straw-like proboscis on the head to uncoil. This allows the butterfly to sip the nectar and in many cases play a major role in plant pollination. Puddling – Sometimes a dozen or more butterflies gather around a puddle or wet place. This activity is known as “puddling.” Since butterflies only eat plant nectar, they need extra minerals and salts to supplement their diets. One way they get those extra nutrients is by sipping them from the water. Tiger Swallowtails are often seen puddling in June. Basking – Butterflies fly best when their body temperature is between 85 and 100 degrees Fahrenheit. If it is colder, they warm up their bodies by basking in the sun with their wings outstretched. Butterflies are commonly seen basking early in the morning. Roosting – Butterflies need a place to roost during the night, and often pick the underside of a leaf. They also roost during rainy, cloudy, and cold weather. Butterflies spend about 14 hours each day roosting, usually from sunset until midmorning. Hibernation/Migration – Butterflies have life cycles of anywhere from a month to a year, a life cycle being the time it takes to go from egg, to larva (caterpillar), to pupa (chrysalis), to adult. The adult stage we see displayed so beautifully usually lasts only a few weeks. Many species produce three or more generations in just one summer; however, regardless of the number of generations in a season, each species in our neck of the woods needs to somehow deal with the onset of winter. Most butterflies, like many insects, respond to our cold winter by “hibernating”—not as adults—but in the egg or larval stage, tucked away under tree bark, in a log, or in the ground. In the spring or summer, they continue their metamorphosis, finally emerging as adults to continue the cycle. Some adult monarch butterflies live more than a year, and respond to winter by fleeing the cold north. These delicate creatures make a 2,000–3,000-mile roundtrip flight from breeding grounds in the northern United States and southern Canada, all the way to the mountains of central Mexico. They then return in the spring. The individual monarchs that make this round trip, do it only once. Upon return, the females produce young, their young produce more young, and, well you get the picture. There are as many as three or four generations of monarchs each summer, the last generation being the only one to migrate. The earlier generations live only a month or two. By the close of summer, the emerging adult monarchs are genetically different from their parents and grandparents—in fact, they are specialized migrators. Instead of devoting energy to producing young, this late summer brood is programmed to migrate back to Mexico, flying to, and brooding in, the exact same tree that their great-great-grandparents did the previous winter. How they do this, nobody knows for sure. The monarch’s breeding ground is here in the north because of the lack of competition compared to the wintering ground in the tropics. This is also where its larval food source, milkweed, is found.When the monarch’s food source dies off in the fall, the newly emerged young adults head south, then west, to brood in warmth until spring. So programmed to make this journey, they choose only the fattiest nectars found along the way, and actually gain weight during this incredible migration.
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