The Caniformia, or Canoidea (literally "dog-like"), are a suborder within the order Carnivora. They typically possess a long snout and nonretractile claws (in contrast to the cat-like carnivorans, the Feliformia). The Pinnipedia (seals and sea lions) evolved from caniform ancestors and are accordingly assigned to this group. Most members of this group have nonretractile claws (the fisher,[1] marten,[2] red panda,[3] and ringtail have retractile or semi-retractile claws[4])[citation needed] and tend to be plantigrade (with the exception of Canidae). Other traits that separate the Caniformia from the Feliformia is that caniforms have longer jaws and have more teeth, with less specialized carnassial teeth. They also tend more towards omnivorous and opportunistic feeding, while the feliforms are more specialized for eating meat. Caniforms have single-chambered or partially divided auditory bullae, composed of a single bone, while in feliforms the auditory bullae are double-chambered, composed of two bones joined by a septum. In the Canoidea, the penis is highly specialized.[5][further explanation needed]