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Caterpillar Soup

Monarch butterfly at Indian Creek Nature Center, July 2017. Photo: Raina Marie Fuller of Madrid.

Caterpillar Soup

By Paul J. Hetzler
November 22, 2017

When it comes to personal growth, the Wicked Witch of the West had the right idea. Quite possibly she got it from monarch butterflies, which must exist in Oz, since they are found worldwide except for polar regions. Many times, a rearrangement of the self-image we have come to know is needed to achieve our fullest potential. In my experience this is always hard, and seldom is it voluntary.

We commonly refer to difficult times, periods of grief or anguish, in terms of dissolution. A person might go to pieces, fall apart, dissolve in tears, or have a meltdown. This latter can describe anything from a childhood tantrum to a coworker who loses composure due to stress. Meltdowns are short-lived.

Breakdowns last longer—weeks, months, even years. People in this state are generally unable to function well, if at all, in jobs or relationships. Nearly all who have breakdowns recover, and afterward it is not unusual for them to seem different. Maybe they have a new perspective; they might choose a trajectory more in line with their dreams. Oftentimes as a result of surviving a very dark period, an individual will shape their life to better suit them, and report being happier than before.

In order to make the dramatic leap from glorified maggot to graceful flying machine, a caterpillar has a complete breakdown, during which it melts down. A caterpillar is of course the juvenile stage of a moth or butterfly, and most are stubby, cigar-shaped, soft-bodied crawly things that somehow become gossamer-winged wonders. We know they enter a pupal stage to change costumes, but until fairly recently we knew more about what went on inside Clark Kent’s phone booth than what happened during pupation. Thanks to electron micrography and other fancy stuff, we now know a tiny bit more.

Some caterpillars produce silk to weave cocoons in which to pupate. Others, for example the monarch, make a chrysalis, a pupal case with a membranous “skin” around it. Once housing is settled, the hard part (by human standards at least) begins. Take the monarch again. Ensconced in its regal, gold-flecked chrysalis, the cute, stripey chub of a caterpillar releases enzymes which dissolve its body. All of it. For a time, that elegant chrysalis is full of nothing but green caterpillar soup. Now that’s a meltdown.

As the caterpillar liquifies, most of its cells burst open. Sort of like hammering to bits one Lego creation to make another, instead of re-using the blocks in new form. There are a few cells, though, which make it through the blender. These are akin to stem cells, and biologists have dubbed them “imaginal cells.” This is wonderfully poetic, as if part of the caterpillar could always imagine flying.

I had heard that a caterpillar’s immune system perceived imaginal cells as foreign material, and would try to eliminate them. This makes for an even stronger metaphor, because we all resist change at first, but alas, science does not confirm this immune-response idea.

In a sense, imaginal cells do foresee the future winged adult, as they contain its DNA, the butterfly blueprint. As far as I can tell, no one knows quite how imaginal cells take those shards of Lego and fashions new kinds of tissue from them. It’s better than magic. There are a few other items in caterpillar soup. From the time it hatches, a larva has within it a fixed number of somewhat flat, more-or-less round structures of highly organized imaginal cells called imaginal discs. Each disc telescopes out like, I don’t know, a telescope or something, to become an appendage such as a leg, wing or antenna.

By the time the pupal chamber unzips and an adult monarch emerges from its chrysalis to rub its bleary eyes, not a drop of caterpillar soup remains. All of it was supped up to serve its new life as a butterfly. If said butterfly belongs to the fourth and last generation of the summer, it might want a cup of coffee before its 3,000-mile trip south. (In spring, monarchs take three generations, relay-style, to get all the way north, but the final brood flies to Mexico for the winter in one marathon shot.)

Writing about chrysali as the cold season begins may seem out of place, but like many, I see winter as a a time to reflect and imagine. And to enjoy some soup while pondering meltdowns and transformations.

By Paul J. Hetzler
Canton, NY

Paul Hetzler is the Horticulture and Natural Resources Educator for Cornell Cooperative Extension of St. Lawrence County.