It’s hard to imagine a creature less like a butterfly than its own caterpillar. This is particularly true for the peacock butterfly – a blue-eyed beauty blinking through the dog days of summer until it’s time to sleep behind the bedroom curtains.
But here comes the peacock caterpillar – like a train made of black polka-dot upholstery armed with great spines, undulating on suckers, propelled by a single idea of destiny behind its blank mask. The last journey the caterpillar takes is alone; it moves away from its writhing knot of siblings in the nettle clump to a safe place to pupate and become something else completely.
Donald Williamson’s theory of hybridogenesis claims the reason butterflies and caterpillars look like such different animals is because they are. The biologist says butterflies and caterpillars do not share a single common ancestor but are the result of evolutionary hybrids: inside the chrysalis, caterpillar cells of a velvet worm hybrid reduce to stem cells then reconstitute the insect hybrid.
I look at this supposed monster, this chimera of a peacock caterpillar, with admiration. The trouble is, the direction the creature is taking leads straight into the traffic. So much for destiny. There are so few butterflies about this year every one matters, so I pick it up and put it back under the nettles.
I am reminded of William Blake’s poem entitled The Sick Rose, where the “invisible worm” is the rose’s “dark secret love” and destroys the flower. Whether this poem is about love and desire, English politics or metaphysics, no one seems concerned for the worm. In the case of insect metamorphosis we may have been persuaded that the rose-like beauty of the butterfly must destroy the worm-like horror of the caterpillar. But both flower and thorn create the allure of the rose.
As I watch the black, spotted, thorny caterpillar renew its journey into another animal’s future, I wonder if we haven’t got the idea of beauty askew. This wonderful creature is not just important for what it might become; the beauty of metamorphosis lies not in a means to an end but in the journey itself.
The Sick Rose
By William Blake
O Rose thou art sick.
The invisible worm,
That flies in the night
In the howling storm:
Has found out thy bed
Of crimson joy:
And his dark secret love
Does thy life destroy.
Originally posted in The Guardian
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