The caterpillar crawls about, looking for a succulent leaf of milkweed to start her busy morning off right. Arising as a pre-butterfly is an honor, and it comes with a heavier workload than she expects. First off, the calorie requirements for cocoon preparation are enormous, and milkweed is so hard to find these days. Flower petals and stems taste better and give a potent energy surge, but she is always hungry again in an hour or so. The learning is intense, especially butterfly prep – cocoon building I and II, cocoon placement, advanced predator avoidance, wing design, and then there is a whole semester of butterfly flight school (this one seems like a ridiculous waste of time for a larva, in her humble opinion). There is hardly time to just enjoy being a caterpillar.
She has been idealistic since beginning butterfly training. But the work is onerous, and she often feels jealous of the pre-moths who have so much time for leisure. This chips away at her resolve. One flower is usually enough for 3 or 4 of them, so they eat together and chortle at each other’s silly stories.
As challenging as the initial learning is, nothing can truly prepare her for the transformation. Just as the rainy months begin to give way to warmer weather, she feels a tingling under her skin and knows it is time to find a secluded, low hanging branch to cling to. She has seen many others spin cocoons, many of whom are great mentors. Still, moving from observation to the real world is intimidating.
It does not take long to find a cool damp spot on a vine tendril resting in a bed of moist leaves where she sequesters herself, sheds her outer skin and begins to spin her silk.
The chrysalis rotation flies by. Three straight weeks of overnight call in a confined space is quite an adjustment. Where the pre-cocoon studies start to drag on and sometimes seem impractical, transformation is non-stop action with a clear purpose. After about a week, she really begins to feel like a butterfly.
Toward the end of her third chrysalis week, exhaustion sets in as her new body begins to congeal. Outlines of wings envelop her and she feels them gradually flesh out and separate. She begins to imagine taking flight and joining the proud ranks of monarchs. Soon she will be ready to emerge.
When hatch day comes, the excitement in the air is electric. She sees many of her fellow young adults drying off their colorful new wings and taking their first flights. They have worked hard and earned their privileged role in sustaining ecosystems. Some good friends will even be part of her migratory cohort.
The opportunity to learn from respected elders, to travel thousands of miles pollinating and showcasing the beauty of her species is awe-inspiring. Oh, and the human children – the joy she will bring to them as they run and give chase with their little nets, giggling and hopping around in the fields like singing crickets jumping through the tall grass. Nature expects a lot from her and, at long last, she is up to the task.
Dr. Jeffery Millstein is a physician at Penn Medicine.
Image by Audrey Luo, a CDY3 at the Perelman School of Medicine.
