The latest BBC nature doc to blow my mind as I go through the David Attenborough catalog is Life In the Undergrowth, an intimate and up-close look at invertebrates from leopard slugs to Ichneumon wasps.
I just can’t say enough about this fascinating doc.
It’s divided up into sections, and so far my favorite is the disturbing and compelling Intimate Relationships, which is not about sex but symbiosis and parasitism.
One story, for example, follows the life-cycle of the Alcon Blue Butterfly, the lovely pale-blue butterfly that flaps over the meadows of Europe.
The Alcon Blue depends on ants to raise its young. The ugly little hatchlings of the butterfly, fat and pink, give off a scent that makes ants treat them like ant larvae. When ants find them, they whisk them off back home to the nest to feed and preen them like their own young.
If all goes well, the caterpillars pupate in the nest and hatch as lovely, pale-blue creatures, walking out of an ant nest dragging wet and wrinkled blue wings, soon to fly away.
But if all doesn’t go well, an Icheumon wasp comes. Huge and antlike itself, it stalks into the ants’ nest, distributing a pheromone that makes the ants attack one another, causing chaos in the nest. It finds an Alcon caterpillar in the ant nursery, and, seeming to sting it, the wasp injects something into the body of the worm. The wasp finds another caterpillar and does the same thing.
The wasp leaves the nest, its work done. The fat pink caterpillars seem none the worse, and are fed and groomed. Soon they pupate, becoming butterflies.
But the Ichneumon had injected their bodies with her egg. As you watch, some of the chrysalises split open to reveal furry newborn butterflies — and others split open to reveal black, shiny wasps. The eggs hatched after the caterpillar entered the pupa stage, and inside the darkness of the chrysalis the wasp larva killed and ate the sleeping butterfly.
It’s chilling and eerie to watch a wasp come out of a butterfly chrysalis. It’s a nightmarish, surreal, Dali-esque image. For every Ichneumon, an Alcon Blue must die.
Charles Darwin had spiritual problems with the Ichneumon wasp. According to Wikipedia, he “found the grisly life histories of Ichneumons incompatible with the central notion of natural theology which saw the study of nature as a way to demonstrate God’s benevolence. In a letter to American botanist Asa Gray, Darwin wrote I cannot persuade myself that a beneficent and omnipotent God would have designedly created the Ichneumonidae with the express intention of their feeding within the living bodies of Caterpillars, or that a cat should play with mice.”
Here’s a less disturbing clip from Life In the Undergrowth, though one almost as weird: a mating pair of hermaphroditic leopard slugs, who entwine and exchange sperm in a weird and beautiful way.
The long version:
Right to the action: