femmenietzsche:

A caterpillar’s body is a squishy sausage of flesh and fluid encased
in a tough outer skin. As it grows it eventually gets too big for its
own skin, at which point it molts: the caterpillar cracks the old skin,
crawls out, and grows a new larger skin.

Each gum leaf
skeletoniser molts up to thirteen times before spinning a cocoon and
transforming into an adult moth. Starting from the fourth molt, the gum
leaf skeletoniser keeps the head shells from its old skins and stacks
them on its head.

Low placed two caterpillars in a petri dish, one with a head shell stack and one without, then introduced a predatory stinkbug into the arena and watched what happened.

The
stinkbug probed the caterpillar with its rostrum, a needle-like mouth
that injects toxins and sucks prey dry. In response the caterpillar
thrashed about, swung its head, regurgitated food and retreated.

The caterpillars without head shells succumbed within 14 seconds, but
the caterpillars with head shells thwarted the predator for at least
120 seconds – although they also succumbed in the end.

Often, the
bug stabbed the head shells instead of the caterpillar, suggesting that
the horn confuses predators. Also, when the bug stabbed the soft flesh
behind the armoured head, the caterpillar swung its horn to deflect the
bug’s needle.

It was a small study, so the results are inconclusive. But Low feels
“very confident that the head shell stack played a part in prolonging
the attack.”

The
gum leaf
skeletoniser.

From Australia, naturally.

Why this caterpillar wears a hat made of discarded heads