| All dogs bark, from the deep bellow of a Great Dane to the shrill yap of a Chihuahua. But there's one exception to this rule: The basenji breed is known as the "barkless dog," though it's not quite silent, either. Instead of barking, basenjis make a yodel-like noise called a "baroo," which sounds more like a howl. This inability to bark is due to the unusual shape of a basenji's larynx, aka voice box. Basenjis have narrower ventricles than other dogs, limiting the movement of their vocal cords and resulting in this sonic oddity. Basenjis' lack of bark makes them useful hunting dogs in their native Central Africa, leading some researchers to theorize they were selectively bred to sound this way. The lack of a loud and less conventional barking noise avoids scaring off prey, and the barooing means they sound more like a jackal or hyena than a hunting dog. While hunting, basenjis also sometimes jump up and down to catch sight of potential prey. In fact, in Swahili, the breed is called m'bwa m'kube m'bwa wamwitu, which translates to "dog that jumps up and down." In addition to the unusual vocalizations, basenjis have a few other unique distinctions compared to their fellow dog breeds. They're known to be quite fastidious, regularly cleaning themselves — much like housecats — so they typically lack a potent doggy odor. Also, female basenjis go into heat only once per year, compared to other breeds that average twice annually. | 
