False-colour scanning electron micrograph of a single barb of the hooked fruit of cleavers or goosegrass, Galium aparine, grasping a strand of Shetland wool. Commonly known as a burr, the fruit contains a single seed. It is dispersed by means of the hooks on its surface, which attach to animal fur or human clothing & are thus transported far & wide. The fruit may also pass undamaged through the digestive system of some animals. The synthetic material known as velcro, used in the clothing industry as a fastener, is based on the same principle as the burr. Magnification: x120 at 6x4.5cm