Cat
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.
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.
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.
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
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