CATS AND DOGS HAVE A SIXTH SENSE Both cats and dogs possess a unique sense organ that people lack. It is called the vomeronasal organ and is located in the roof of the mouth. Two small openings just behind the front teeth connect the vomeronasal organ to the outside air. To activate this sense, the animal sucks air into its mouth. Scientists know that the vomeronasal system is related to the sense of smell. They think that cats and dogs may use this system in mating to get special chemical information about animals of the opposite sex. You can tell when your pet is using its vomeronasal sense by watching its behaviour- it is especially easy to spot when a cat is using it because the cat shows an odd behavior called "flehmen." During flehmen, the cat opens its mouth slightly, pulls back its lips, and inhales, drawing scent molecules tip into the openings leading to the vomeronasal organ. Flehmen means "grimace" in German, and a cat doing this does look as though it is grimacing with disgust. A MOST AMAZING STORY OF A HUMAN-ANIMAL FRIENDSHIP? Bobby, a Skye terrier who lived in the 1800s, was probably history's most devoted pet. Bobby was the best friend of a Scottish shepherd named John Gray. When John Gray died in 1858, he was buried in Greyfriars Churchyard in Edinburgh, Scotland. The day after the funeral, Bobby appeared at his master's grave. He stayed there, sleeping on the grave each night, for the next fourteen years. His story was told around the world, and tourists flocked to the churchyard to see the amazing little dog, who became known as Greyfriars Bobby. Bobby died in 1872 and was buried next to John Gray in the churchyard. Today a bronze statue of bobby, which sits atop a drinking fountain for dogs, has become an Edinburgh landmark. WHAT A TORTOISESHELL OR CALICO CAT IS AND WHAT IS SO ODD ABOUT THEM? A tortoiseshell cat is one whose fur is a mottled black and orange color. A calico cat is black and orange with patches of white. The odd fact about both these types of cat is that they are almost always female. Male calico and tortoise shell cats are very rare. Only one in every three thousand calico cats who lives past kittenhood is a male. The explanation for this strange occurrence comes from genetics. In the cells of all animals are threadlike structures called chromosomes. Carried on the chromosomes are tiny coded messages known as genes. An animal's genes determine almost everything about whether it is male or female, what colour its eyes, skin, and hair (or fur) are, and so on. Chromosomes come in pairs. One of these pairs determines whether the animal will be male or female. Females have two X chromosomes, while males have one X and one Y. In cats, the coded messages for black and orange coat color are carried on the X chromosome, but not on the Y. A male cat, because he has only one X chromosome, can be either black or orange. In order to be black and orange, the cat needs two X chromosomes, one carrying the gene for black fur and one carrying the gene for orange fur. Since any animal with two X chromosomes must be a female, all black and orange cats are female. The rare male calico or tortoiseshell cat has three sex chromosomes, two X and one Y. Next Trivia Page Return To Menu