Rats. Debbie Ducommum

communicate with sounds beyond our range of hearing. Baby rats emit ultrasounds to call their mothers, males use them when fighting, and all rats laugh in ultrasound when playing. Rats squeak audibly when annoyed or defensive, and they screech when hurt or terrified. They express other strong emotions such as agitation, frustration, or contentment by grinding their teeth.

      Body language is important to rats. They claim territory or declare their status by shuffling or scraping their hands on the ground. In a confrontation, a rat may hold her tail out stiffly and rattle or vibrate it. An aggressive rat puffs out her hair and arches her back and may hiss. In a fight, rats push their shoulders against each other as a test of strength before grappling and biting. They may also stand on their hind legs and box.

      A rat expresses submission just as a dog does, by putting her ears back, holding her head down, laying down, or rolling on her back. Some rats seem to wag their tails when happy, and some may shudder or shiver when excited or nervous. A rat stretches and yawns when waking up, but this behavior can also be a greeting. A rat who is playful and excited jumps and twists, scampers, and runs around in circles. A curious rat does a lot of sniffi ng and may rear up on her hind legs. And just like puppies, rats explore new items by licking, nibbling, and chewing on them.

       In this temple In India, wild rats are revered and fed by people who visit.

       Equivalent Aging Schedule

Rat Age	Human Age
5 weeks	10 years
6 months	16 years
9 months	25 years
1 year	35 years
18 months	50 years
2 years	65 years
3 years	85 years
4 years	100 years
5 years	110 years
6 years	120 years
7 years	130 years

      It is unknown how long wild rats live, although studies have shown the average age of colony members is only six months. Wild rats probably do not live past a year or two. As their reflexes slow down, they are more vulnerable to predators such as owls, snakes, foxes, and weasels in the country, and dogs and cats in the city.

       The elephant-headed Hindu god Ganesha is often portrayed on the back of a rat.

      Domestication of the Rat

      Domesticated rats are physically much the same as wild rats, and they behave much the same as wild rats; however, the behavior of domesticated rats differs from wild rats in several ways. During the process of domestication, rats were selectively bred to be more docile and accepting of human handling and restraint. Domesticated rats are less aggressive, less fearful of humans and new objects, and less predatory than their wild counterparts.

      Domesticated rats reproduce more quickly than wild rats, reaching sexual maturity earlier (as early as five weeks) and having bigger litters. These are the same qualities that separate other predatory domestic animals, such as dogs and cats, from their wild ancestors. Domesticated rats are true domestic animals and would have trouble surviving on their own in the wild.

      Young domesticated rats do not need to be tamed; they need to be socialized. Every animal species has a critical period of development when it most easily bonds to other individuals. In rats, the critical socialization period is two to six weeks of age, with two to four weeks being the most critical. Handling and petting baby rats of this age for just a few minutes each day ensures that they are socialized to humans, and the more they are handled, the friendlier they will be.

       The adaptable wild Norway rat is the ancestor of the domesticated rat.

      Fully socialized rats accept people as part of their family, interacting with their two-legged family members as if they, too, were rats. Rats will groom, play, sleep, and eat with the human members of their family. It is this ability to form strong social bonds that makes rats such delightful companions.

       Rat lovers come in all ages.

      Varieties

      Rats haven’t been domesticated long enough for true breeds to develop, but many varieties of rats exist. Currently, there are thirty colors, ten patterns, six coat types, and three body forms that can be mixed and matched, with new varieties being developed all the time. Most pet shops carry only smooth-coated rats in the most common colors—agouti, black, beige, and white—in either solid or hooded patterns. The hooded pattern is unique to rats; they appear to be wearing a colored hood over the head and shoulders, with a stripe or patch of color down the back.

      Rats can be found with rex, velvet, velour, or satin coats, and some have hardly any hair at all. Rex rats have curly hair. The velvet coat is short and plush, while velour is short and fuzzy. A satin coat is extra shiny.

      A rat’s yawn may be a type of greeting.

      Hairless rats can have pink or dark skin. In one type of hairless rat, called the patchwork hairless, short hair grows in patches or stripes that seem to move around as the hair falls out and grows in elsewhere. Other hairless rats retain short, sparse hair on their faces all the time, while some are completely hairless except for their whiskers. All hairless and rex rats have curly or crinkled whiskers. One rodent club calls its hairless rats sphynx after a hairless breed of cat.

      Although some people are repelled by the naked skin of a hairless rat, many are not and think hairless rats look more like people. Some people admit the hairless is their favorite variety of rat. Hairless rats look and are more vulnerable and require some special care. They can’t tolerate extreme cold, although they do fine at temperatures down to 65° Fahrenheit (F). Since they don’t have eyelashes, some of them get debris caked under their eyelids, which needs to be cleaned out whenever it accumulates to prevent eye damage. Their delicate skin is also vulnerable to scratches. Some patchwork hairless rats die soon after birth, and some hairless females have trouble producing milk.

      Rats are excellent climbers, using their tails to balance and steady themselves.

      Another variety of rat is the odd-eyed. These rats have eyes of different colors, usually one red or pink, and the other black or ruby red. Odd-eyed rats are more common in certain colors, but breeders are trying to develop them in all colors and varieties.

      One of the newest varieties of rats is the