The first incisor is the smallest, and the third is the largest, the difference in size being most marked in the upper jaw. The canine teeth are strong, recurved, pointed, elongate, and round to oval in section. The premolars are usually adapted for cutting, and the molars usually have four or more sharp, pointed cusps. The last upper premolar and the first lower molar, called the carnassials, often work together as a specialized shearing mechanism. The carnassials are most highly developed in the Felidae, which have a diet consisting almost entirely of meat, and are least developed in the omnivorous Ursidae and Procyonidae.
Most carnivores are terrestrial or climbing animals.
Two genera, Potos and Arctictis, have prehensile tails. Land-dwelling carnivores shelter in caves, crevices, burrows, and trees. They may be either diurnal or nocturnal. Most species of the Canidae, Mustelidae, Viverridae, and Felidae live solely or mainly on freshly killed prey. Their whole body organization and manner of living are adapted for predation.