Spines: Cactus spines are modified leaf lacking vascular tissue that arise multiply from the areoles and detach easily. They are classified into central spines located centrally on the areole and radial spines around the margins, they can be stout and woody or fine and hair-like, woolly, bristly, needle-like, barbed, hooked or curved and variously coloured. . They protect the fat stem against some predators, even if inefficiently, but their most important function is to condense atmospheric moisture from dews, fog and rain (spines operate as a drip tip) so that they drip to the ground near the base of the plant for uptake by the superficial root system. Often spines protect plants from the sun and from extreme temperatures helping to preserve the plants from drying out. They also consent to camouflage the plant (mimesis).