Many people are familiar with the spiny appearance of sea urchins, but most have probably never noticed the pedicellariae that grow between the spines. Each one is less than a millimeter across, and they come in several different types, some of which are more suited to cleaning away algae than fighting off predators. Collector urchins have a particularly fearsome variety of pedicellariae consisting of stalks topped with biting jaws. The three sections of the jaws open outward like flower petals, each one ending in a venomous fang. A dense forest of these structures covers the collector urchin's shell, waving and snapping in response to touch, chemical signals and looming shadows.
Four of the urchin species kept their pedicellariae, but the collector sea urchins released a continuous stream of the biting appendages. In the original experiments, collector urchins released tens of pedicellariae per trial, but in subsequent tests, which have not yet been written up and published, they spewed hundreds over the course of 30 seconds
Apparently fighter drones aren't a new invention.