Why would little Mittens hide under the bed at the slightest sound, whereas Felix loves to cuddle with strangers? What makes Moxie scratch and bite when Henri would never unsheathe his claws? Despite the fact that cats most popular pets along with dogs, scientists are just now figuring out what makes one cat friendly and another a grouch. From pedigreed breeds to domestication, here are six secrets to a cat’s personality. Their own masters Cats really are the masters in the human-feline relationship. The feline is one of the few animals that domesticated on its own. The domestic cat arose from a wild ancestor cat called Felis silvestris lybica in the Near East and Africa, sometime between 10,000 and 20,000 years ago. But though humans have bred specific dogs together for desired traits, such as goat herding or hunting, for thousands of years, until the Victorians began breeding housecats about 200 years ago, cats have never been caged and captive bred. That means natural selection, not artificial selection, led to the personality traits seen in domestic cats today. Key window There is no genetic difference between house cats and feral cats that live outdoors and fend for themselves on the mean streets. Most house cats come from feral cats that made it past the first six months of life. As a result, most of what makes a cat socialized is his early experience with humans. In two studies in the 1980s, Temple University researcher Eileen Karsh and colleagues found that cats handled by humans between 3 weeks and 7 weeks of age tend to be friendly and social. But if the felines make it past 7 weeks old without any human touch, they’ll be the skittish kitties that hide under the bed when guests come over. Daddy’s kid In a 1995 study detailed in Applied Animal Behaviour Science, researchers found that the tomcat has a strong influence on the personality of the kitty it sired. The team created two litters of kittens: one that had been sired by an aloof tomcat and one that had been sired by a friendly and social male. At 1-year-old, the friendliest cats were those handled by humans as youngsters and sired by the friendly tomcats. The least friendly were those that came from aloof tomcats and were left to their own devices. Other research has found a friendly mother tends to rear friendly kittens. But because moms raise their young, it’s not clear whether the moms are passing on their social ways through genetics or through imitation. After all, kittens could be learning to be bold or scaredy-cats by watching their mom interact with humans. Breed personalities? Persians are more aloof, Siamese are a dog-like breed and Maine Coons are friendly but not lap cats. At least, that’s the lore in cat fancier circles. But while those tales may be true, only a few studies have looked at cat personality in any depth. In a study described in “Companion animals and us: exploring the relationships between people and pets,” (Cambridge University Press, 2000), the caretakers of Siamese cats rated their felines as more affectionate, playful, curious, friendly to strangers and chatty than non-pedigreed cats. Persians were rated as friendlier and more affectionate to the owner, but also fussier about food and cleanliness than the average mutt cat. Grumpy cats Despite their sinister appearance, the hairless sphinx cat may be the most affectionate — perhaps because their furless body needs more human snuggling to keep warm, according to a study published in 2012 in the Journal of Veterinary Behaviour. The least friendly cats were the mixed breeds, known as domestic shorthairs, the study found. Then again, purebred cats may be friendlier on average because they spend more time with their mothers being socialized than those picked up on the street after weeks of hard knocks. Either way, for most breeds, there’s little data to back up proud owner claims that their Snookums is friendlier, smarter or better at using a flush toilet because of its pedigree. Interspecies love Cats are notoriously independent animals, and most cats that were reared on their own tend to thrive in single-cat households. Introducing a second pet can be stressful and problematic in later life. But if cats have been reared with other kittens from birth — such as siblings — they are often playmates for life. Cats introduced to other animals between ages 3 weeks to 7 weeks may also become best buddies with animals that would otherwise be enemies or even prey in the wild. Cats and dogs often coexist in harmony, and felines and birds or hamsters have even been known to be friends. Still, it’s probably not a good idea to leave a cat and its natural prey alone, lest the feline’s hunting instincts take over.