Amblypygids walk on three pairs of legs. The first pair is antenniform: greatly elongated, finely segmented at the tip, and covered in sensilla that detect touch, air movement and airborne chemicals. The animal holds them out and taps, probing surfaces the way a blind person uses a cane.
Those feelers support genuine navigation. Field experiments with Neotropical species have shown individuals displaced several metres from a home tree returning to it at night through structurally complex rainforest, and performance degrades sharply when the antenniform legs are impaired. The brains of amblypygids have unusually large mushroom bodies, the arthropod structures associated with learning and spatial memory.
Despite an alarming appearance, amblypygids have no venom glands, no sting and no silk. They capture prey by striking with spined pedipalps. The relative contribution of olfaction, mechanical cues and possibly other modalities to their homing is not fully resolved, and the experiments have covered only a handful of species.