An Exercise in Active Learning (Grades 2-4)
It was the end of July and the next several days were warm and sunny. Across the meadow, on some nearby milkweed plants, things were beginning to happen. It was time for the next generation of Monarchs to come out of their eggs and the cycle to begin once again.
A tiny caterpillar poked his head through a hole he had eaten in his eggshell. Once out, the barely visible speck made a first meal of his empty eggshell. Gulliver's adventures were about to begin. Searching around for more of his kind he found nothing because his mother had only laid one egg on the leaf. But having finished his eggshell he did not have to go far to continue feeding. His mother had chosen a succulent and nutritious plant upon which he could feed.
Like most caterpillars, Gulliver was very particular about what he would eat. However, his mother had solved that problem for him and he had a built in supply of food right were he was. His mother was a good botanist. The principle business of his life right now, which was eating, could begin. Gulliver started up the leaf, eating all the way. He loved to eat leaves and so all day he ate the succulent milkweed leaves that surrounded him. As the day came to an end, when the temperature dropped and the air around him cooled down, he stopped eating temporarily and remained still in his place under the leaf.
In the early morning, when the sun came up, Gulliver was hungry and crawled up on top of the milkweed leaf. He now found that he had lots of company on the milkweed plant. The leaves around him were covered with other specialized insects brightly colored with contrasting patterns, such as himself, with one mission in life- gluttony. There seemed to be plenty for everyone and they must eat enough to nourish themselves for now and later.
Some of the eggs Gulliver's mother had laid in the milkweed patch never hatched and others were eaten by mites, ants and other insects. Even so, at first there were many Monarch caterpillars but some of the new caterpillars were found and eaten by predators such as spiders, wasps, stink bugs, and earwigs. Others were parasitized by flies and wasps. The milkweed patch was a dangerous place but Gulliver managed to escape detection by these predators and parasites and he continued to feed and grow.
After two days of eating, Gulliver stopped. He had gotten very fat from eating almost constantly. His skin did not fit him any more. But that did not matter. He simply burst out of himself and there was a newer, larger, looser one underneath the old one.(4) He was almost twice as big as he was before. Now he had lots of room and could begin eating again. The first thing he ate was his old skin. Having done that he started eating the milkweed leaves once again. He and the other caterpillars ate and ate until a few days later when, as before, he needed to shed his skin again
Soon, Gulliver was in his fourth new skin. Each time this happened he stopped eating briefly, molted, and then began to eat again. There were even fewer caterpillars around now than there had been earlier. He had seen some of the others fall victim to larger things that flew and crawled around the milkweed plants. He had been one of the lucky ones and had escaped harm so far.
Late one afternoon, as Gulliver was busy eating away, the air around him began to bend and twist the leaf he was on and the light around him seemed to disappear. It was no longer warm and sunny. Was it time to stop for the day? It was cool now and the sky had gotten very dark. Strange. He was not through eating for the day. What was happening? There were bright flashes of light and loud noises he had not heard before. The world around him seemed to tremble. Gulliver and the other caterpillars seemed to sense a change was coming and began to move to the undersides of the milkweed leaves. He found a large leaf near the bottom of the plant and quietly waited.
Large wet drops began pelting the milkweed plant and Gulliver remained very still in his hiding place beneath the leaves. The rain was everywhere and it seemed like it would never stop. Suddenly he felt himself surrounded by water. It had reached his hiding place and was rushing past him tugging at his leaf. He hung on but soon lost the battle and was swept away. What's happening? Where was he going?
Wet and weary, Gulliver finally came to rest. It had been a tiring trip. He crawled up the stem of a nearby plant and fell asleep for the night. When Gulliver awoke the next morning, he was alone. There were no other caterpillars around. Where was everybody? Where was he? He had never left his plant before and he had no way of knowing where it was. This place was not familiar. However, he was not hungry anymore and did not feel like eating. He had become solid and heavy. Gulliver was fully grown and instinct told him it was time for something else to happen. He began looking for a "special" place. He wandered restlessly for a short distance.
Finally, he crawled to a high, sheltered spot underneath the edge of one of the logs in an old wood pile. He moved back and forth lifting his head occasionally as if he were trying to determine the best spot. With each movement of his head, he lay down a silken thread from his spinneret. At last he chose a spot and began to spin a tiny white button to which he hooked his two back legs. Slowly, his remaining legs let go, a pair at a time, until, finally, he swung his body head-downward. He was very still and looked like a black and yellow striped "J". The long black filaments, or feelers, behind his head hung limp.
What he once had been was changing. He was no longer a caterpillar but was becoming something else. It was time to remodel and get a new look.(5) In about a day, Gulliver was ready to molt for the last time. He began stretching his body and gradually his old skin split at the top of the thorax just behind his head and was slowly pushed off little by little as he had done four times before. This time, however, he would look completely different. His black and yellow stripes began to disappear and he became a wiggly green blob turning and twisting like an acrobat until at last his old skin dropped to the ground. There it lay looking like a dead leaf.
Gradually, the soft green blob became smooth and hard. Gulliver was now surrounded by a very pretty pale jade-green case called a chrysalis. It was marked with tiny golden spots like beads that glistened in the summer sun. There was no more movement. All was still but much was about to happen.