The Basenji is one of the few breeds to originate from Africa, where it was kept as a hunting dog for many years before becoming known in the West. Although these dogs can make sounds, the structure of their larynx is different, so that the vocal cords cannot vibrate as strongly. As a result, they cannot bark like other breeds, but make chortling noises. This is an anatomical peculiarity, but causes no problem for these unusual sleek smooth-coated dogs. Basenjis are being bred quite regularly in the UK now, but you may have to be patient for a puppy, because unlike virtually all other domestic dogs, Basenjis have just one period of reproductive activity or 'heat' per year, rather than two.