Metamorphosis used to be a benchmark for wonder at the natural world. Where did that go?
Perhaps I’m concocting nostalgia for a non-existent childhood, but I remember primary school science lessons that featured the near-miraculous transformation from caterpillar to butterfly (and it was always caterpillar to butterfly) as a major selling point for science’s inherent aesthetic value. From simple to complex. From ugly to beautiful. From boring to fascinating. Good stuff.
The reason I’m not sure about whether or not my brain is playing tricks on me is that I haven’t seen metamorphosis used in that context for years. Does it still happen? I must admit I spend very little time in primary school classrooms these days. Can someone report back from the field?
But outside the classroom, metamorphosis has been used in symbolic storytelling so often that, at this point, we might as well rename it metaphor-phosis. (I’m not ashamed, not even for a second.) And as a metaphor, I suppose it makes sense. The process behind the butterfly appearing in place of the caterpillar seems mysterious and implausible, in the same way as changes in our own lives sometimes seem. Butterflies are a symbol of resilience through “formative” hardship, of our true or revealed selves, and of rebirth.
Of course, the scientific reality of metamorphosis messes a little with its symbolism. A great deal of insects — those in the taxonomic grouping Holometabola — undergo the process, not just butterflies. This includes wasps, ants, bees, beetles, moths, flies, fleas and mosquitos. When was the last time you saw a blowfly used as a symbol of rebirth? All of these species transition from tiny, wriggly larvae to more-or-less elegant adult forms, via a pupal stage, where all the magic happens.
The term 'metamorphosis' isn’t wholly correct, either; the term refers to any physical development after birth, which certainly happens to non-insects as well. The classic butterfly situation is 'complete metamorphosis,' wherein the organism progresses through four life stages: egg, larva, pupa and adult. Insects that don’t do that (like dragonflies, aphids and grasshoppers) undergo 'incomplete metamorphosis,' during which they have three life stages: egg, nymph and adult. Nymphs usually look like tiny adults, and so don’t undergo a radical change as they progress to sexual maturity.
Far from being a mysterious process, complete metamorphosis has been studied at the molecular and genetic levels for decades. An intricate network of genes coordinate the deconstruction of the larval body and subsequent construction of the adult body, as specialised hormones flood the tissue and keep the process ticking along.
As an inherently interesting phenomenon, this has caught the attention of many curious scientists, but there are also slightly selfish reasons for humanity to care about what happens inside a pupal case. Many agricultural pests undergo complete metamorphosis, as do vectors of diseases like malaria, trypanosomiasis and dengue fever, so it’s in our interests to learn how to stop their growth before they become sexually mature adults. Once the underlying mechanisms are learned, it’s possible to develop specialised insecticides that are non-toxic to non-metamorphosisers and work far more efficiently than conventional chemical sprays.
Much research into insect biology is filtered through this lens, and as a fan of insects regardless of their medical or agricultural utility, it does sometimes rub me the wrong way. Until a good majority of the general population learns to love the beauty of wasps and flies, however, it may be the only way to coax research dollars from their pockets. Why hasn’t this happened already? Memories of childhood science lessons aside, the cultural fixture of complete metamorphosis as a symbol should, in theory, be drawing everyone to its scientific explanation. But maybe the macroscopic process is enough. After all, what is more magical than to skip from child to adult, fully-formed, without any of that messy stuff in between?
There's more magic to be found in this issue of Lateral, where we talk in depth about many different types of transformation occurring in the sciences and throughout society. I hope you enjoy reading it.