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Cat

 

Environment

The wild cat, ancestor of the domestic cat, is believed to have evolved in a desert climate, as evident in the behavior common to both the domestic and wild forms. Wild cats are native to all continents other than Australia and Antarctica, although feral cats have become apex predators in the Australian Outback where they are menaces to wildlife.[citation needed] Their feces are usually dry, and cats prefer to bury them in sandy places. Urine is highly concentrated, which allows the cat to retain as much fluid as possible. They are able to remain motionless for long periods, especially when observing prey and preparing to pounce. In North Africa there are still small wildcats that are probably related closely to the ancestors of today's domesticated breeds.

Cats enjoy heat and solar exposure, often sleeping in a sunny area during the heat of the day. Cats prefer warmer temperatures than humans do. People start to feel uncomfortable when their skin's temperature gets higher than about 44.5 °C (112 °F), but cats don't start to show signs of discomfort until their skin reaches about 52 °C (126 °F).

Being closely related to desert animals, cats can easily withstand the heat and cold of a temperate climate, but not for extended periods. Although certain breeds such as the Norwegian Forest Cat and Maine Coon have developed heavier coats of fur than other cats, they have little resistance against moist cold (eg, fog, rain and snow) and struggle to maintain their 39 °C (102 °F) body temperature when wet.

Most cats dislike immersion in water; one major exception is the Turkish Van breed which has an unusual fondness for water.[36] Abyssinians are also reported to be more tolerant of water than most cats.

Reproduction and genetics

Four kittens being nursed

Four kittens being nursed

Cats are seasonally polyestrous, which means they may have many periods of heat over the course of a year. A heat period lasts about 4 to 7 days if the female is bred; if she is not, the heat period lasts longer.

The male cat's penis has spines which point backwards. Upon withdrawal of the penis, the spines rake the walls of the female's vagina, which may cause ovulation. Because this does not always occur, females are rarely impregnated by the first male with which they mate. Furthermore, cats are superfecund; that is, a female may mate with more than one male when she is in heat, meaning different kittens in a litter may have different fathers.

The reproduction process is usually very loud, as both cats vocalize loudly. If one is not used to the sounds of cats mating, it will sound like a cat fight.

The gestation period for cats is approximately 63-65 days. The size of a litter averages three to five kittens, with the first litter usually smaller than subsequent litters. Kittens are weaned at between six and seven weeks, and cats normally reach sexual maturity at 4-10 months (females) and to 5-7 months (males).

A kitten that has opened its eyes for the very first time.

A kitten that has opened its eyes for the very first time.

The pregnant cat will exhibit physical and personality changes. Pregnant cat physical changes include abdominal enlargement, vomiting, increased appetite, pinking of nipples, and cessation of heat cycle. Pregnant cat personality changes include nesting behavior during the terminal stages of pregnancy and also increased affection throughout the stages of pregnancy.[37]

Cats are ready to go to new homes at about 12 weeks old (the recommended minimum age by Fédération Internationale Féline), or when they are ready to leave their mother. Cats can be surgically sterilized (spayed or neutered) as early as 6-8 weeks to limit unwanted reproduction. This surgery also prevents undesirable sex-related behavior, such as territory marking (spraying urine) in males and yowling (calling) in females. If an animal is neutered after such behavior has been learned, however, it may persist.

Blue-eyed cats with white fur have a higher incidence of genetic deafness.

Blue-eyed cats with white fur have a higher incidence of genetic deafness.

The domestic cat and its closest wild ancestor both possess 38 chromosomes, in which over 200 heritable genetic defects have been identified, many homologous to human inborn errors. Specific metabolic defects have been identified underlying many of these feline diseases. There are several genes responsible for the hair color identified. The combination of them gives different phenotypes. See Cat coat genetics.

Features like hair length, lack of tail or presence of a very short tail (bobtail cat) are also determined by single alleles and modified by polygenes.

The Cat Genome Project, sponsored by the Laboratory of Genomic Diversity at the U.S. National Cancer Institute Frederick Cancer Research and Development Center in Frederick, Maryland, focuses on the development of the cat as an animal model for human hereditary disease, infectious disease, genome evolution, comparative research initiatives within the family Felidae, and forensic potential.

It is a common misconception that all white cats with blue eyes are deaf, leading to some people rejecting blue eyed white cats as pets. This is not true, as there are many blue eyed cats with perfect hearing. However, white cats with blue eyes do have slightly higher incidences of genetic deafness than white cats of other eye colours.

 

 

 

Wikipedia

 

http://en.wikipedia.org/w/index.php?title=Cat&action=history

 

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