selective focus photo of gray tabby cat

The cat or domestic cat (Felis silvestris catus) is one of man’s oldest pets. The domesticated cat belongs to the feline family (Felidae). The word cat is also common, sometimes more specifically in the case of a female cat. A male cat is called a male cat, and a young kitten a kitten.


The scientific name of the cat was published in 1758 as Felis catus by Carl Linnaeus in the tenth edition of Systema naturae. The name of the wild cat, from which the domesticated cat is descended, was published in 1777 by Johann Christian von Schreber as Felis silvestris. Of the vast majority of animals that are domesticated, the scientific name is derived from the name of the wild ancestors. In 2003, the International Commission on Zoological Nomenclature established in Opinion 2027 that this principle should be followed for all domesticated species, and that the name of the wild species has priority over that of the domesticated form, even if the latter was published earlier. If the domesticated cat is considered a subspecies of the wild cat, then the correct name is for the species Felis silvestris, and the trinomen is for the subspecies Felis silvestris catus.


The lifespan of domestic cats roughly matches that of other felines. After ten years, a cat can be considered elderly. Cats die on average after fourteen to sixteen years. The oldest cat in the world lived to be 38 years and 1 day old. In general, ages are difficult to verify because cats do not have birth certificates. Breed cats do have this, but on average they do not live as long, about 10-13 years. This is due to congenital diseases that are more common in purebred cats as a result of a high inbreeding coefficient. A similar picture is seen in purebred dogs, by the way.



A cat’s skeleton consists of 250 bones. Like all other carnivores (meat eaters), cats are equipped to hunt and devour prey. Cats have a fairly round head and a short snout, large eyes, sensitive whiskers at the mouth and sharp upright ears. They have short broad jaws with strong snap molars and sharp incisors. Cats have a total of 30 teeth. In the upper jaw, they have 6 incisors, 2 canines, 6 front molars and 2 molars. In the lower jaw, they have 6 incisors, 2 canines, 4 front molars and 2 molars. Their jaw cannot chew, the cat tears its food and uses the very strong stomach acid to digest the food. The tongue is covered with a layer of rough papillae that is useful for personal grooming. The female cat’s tongue is rougher than the male cat’s; this allows her to wash her young better.


Cats have five toes on both front legs and four toes on the hind legs. The first toe is located a little higher on the foreleg than the other four toes. This first toe does not touch the ground while walking, but it is used in grooming and when grabbing prey. At the ends of the toes are strong, sharp, curved claws. The nails can be retracted. This mechanism is a distinctive feature of the cat family Felidae. Sharpening the nails on a tree (in the home, a scratching board or scratching post) keeps a cat’s nails sharp. The sides that grow out then become loose and are removed with the teeth, keeping the nail at length with a sharp tip.


The cat uses its tail as an organ of communication between conspecifics and in maintaining balance. Its flexible spine allows the cat to turn around and land on its paws in the event of a fall. This is only possible with a fairly high fall so the animal has the space and time to do this. There are also cats with short or missing tails. On the Isle of Man there is a breed with very short or completely missing tails, the manx. In the Far East, there are cats with tail stubs or curved short tails. In Japan, a breed was bred from these, the Japanese stub-tailed cat.

Primordial pouch

Cats often have a primordial pouch or primordial pouch. This is a visible fold of skin at the level of the abdomen, in front of the hind legs. The fold has several functions. It enables the cat’s mobility; the fold allows the cat to eat a lot without the skin being stretched; it is an extra protection in fights involving kicking with the hind legs


Most cats have good eyesight and can see well in the dark because they have more rods than cones in their eyes. This allows them to perceive well at dusk, but in complete darkness they see nothing. In contrast, their ability to distinguish colors is weak, but cats are not colorblind. According to a 2014 study, cats, among a number of other mammals, may be able to perceive ultraviolet light. On the back wall of the eye is reflective tissue (the tapetum lucidum), which makes a cat’s eyes sparkle in the dark. A cat’s field of vision is 285°, versus a human’s 210°. The pupils have a vertical slit as their shape. Each eye is protected by a third eyelid, also called a cuticle.

Cats have excellent hearing and are able to perceive frequencies up to 64 kHz. By comparison, an average human hears frequencies up to 20 kHz. The ears can rotate 180°. This allows sounds to be localized well.

The whiskers have a function in instinctively biting through the spine of prey. Cats do not see sharply at close range and therefore rely on their highly sensitive whiskers and the long hairs above the eyes when handling prey. Cats without whiskers have difficulty performing the “coup de grâce” (killing the prey). Cats also have whiskers on the back of their front legs.

The hairs in the fur are individually connected to a mechanoreceptor. This allows information about the environment to be sent to the brain. As a result, most cats also enjoy being petted and quoted.

A cat’s nose contains about 20 million scent cells, four times as many as in a human. The nose is especially attuned to nitrogen because this substance is found in decaying food. This also makes the cat good at judging food for edibility. Cats are not scavengers by nature. Cats’ sense of smell is not as well developed as that of dogs.

A cat has about 500 taste buds, while a human has over 9,000. Cats are therefore mainly guided by smells. Cats can distinguish salty, sour and bitter, but have no preference for sweet.



Cats are very agile: they can travel short distances quickly and they are good climbers. Unlike dogs, cats have limited stamina. Cats usually do not like water, but they can swim well. They hunt their prey by silently stalking them. When close enough, the cat will pounce on the prey and catch it with its sharp teeth and claws. The tendency to play with the wounded prey for a long time is observed in all felines, including the domesticated cat. It is a means of defusing the prey without injuring itself if it defends itself by biting.

Cats conserve their energy during the day: they are twilight active animals.


Like lions and tigers, cats lick themselves clean with their tongues; they often do this before going to sleep, or after waking up. The instinctive grooming of the fur with teeth, saliva containing enzymes and fat from a gland above the tail requires about two hours a day. As a result, the cat swallows many loose hairs. These usually leave the body through the intestinal tract. However, if the cat ingests too many hairs in a short period of time, a hairball may form and be vomited out. Long-haired cats suffer more from hairballs than short-haired ones, by the way. If a cat makes futile attempts to regurgitate a hairball, there may be constipation. This can be life-threatening.

Social behavior

The domesticated cat is a socially adaptable species. In an environment with scattered food sources and low population densities, cats live solitary or in small groups of closely related females. The larger, non-overlapping territories of males occupy two or more of the smaller territories of females. In urban environments or farms, food sources are more centralized, leading to the formation of high-density groups consisting of multiple males and multiple females with smaller, overlapping home-ranges and a promiscuous mating system. Depending on the availability of food resources, cats are thus solitary or social animals. If they have the opportunity, females will form family groups. Their female offspring stay with them and in turn have kittens, creating a matriarchal group. The male animal leaves the group when they become sexually mature.


Cats make a low buzzing sound called purring. It is a way of expressing all kinds of feelings, from fear and pain to contentment. When interacting with humans, it is usually a sign that they are content, sometimes that they need help. This sound is produced by vibrations of the vocal cords. Purring is a means of communication between kittens and mothers. Kittens can purr when they are a week old.

In addition, a cat can meow (or meow), growl, hiss, blow, scream, squeak. Clacking teeth, moaning and twitching (where the cat sometimes makes a “mewling” sound) a cat does during the flehmen response.

Communicating with cats

There are several communicative signals from cats that they also understand when given by humans. Communicating with a cat will mutually strengthen the bond with the cat. Some examples:

  • Blow: the hissing sound of blowing indicates that a cat is afraid and does not want to be approached. So blowing at a cat yourself as a “punishment” makes no sense, you are signaling that you yourself are scared and want to be left alone.
  • Squeezing both eyes (slowly): in cat language, staring is a threat. Squeezing the eyes together means that a cat has nothing bad in mind and thus serves to prevent aggression.
  • Purring and sticking out nails at the same time: the cat means that he feels safe with humans.
  • Giving head: in the cheeks of the cat are scent glands. By giving heads against objects, the cat marks that object. The scent gives the signal that everything is “safe” and gives a feeling of “home”.
  • Holding by the neck skin: contrary to popular belief, a mother cat never takes her kittens by the neck skin. She does, however, take them by the neck muscle. She does this until about 3 weeks of age, when she takes the kittens to a new litter or wants to take them back to the litter. Taking in the neck skin to punish cats never does. Only at mating will the male bite the female in the neck skin to fix her.



Female cats or females are in heat an average of two to three times a year, but this is highly variable: some females go into heat every two weeks throughout the year, while others only go into heat once a year. This is most common between January and April, but also between June and September. Because the hormonal cycle depends on the number of hours of daylight, a female cat is rarely in heat between October and December. Cats that are often indoors in well-lit homes will still go into heat year-round. A cycle lasts about two weeks. In this, however, the female cat is fertile for only two to four days. She will clearly communicate during this period that she is in heat by calling out to potential mating candidates. During this period, a female cat may also start spraying urine. The male cat may answer this call, after which they will know from each other that there is approval from both sides.

When mating, the male cat bites the female cat on the neck and ejaculates soon after his penis is in the vagina. The tip of the penis is covered with barbs that stimulate ovulation. A female cat and male cat can mate several times a day. A female cat can also be fertilized by more than one male. A litter of kittens can also be from different fathers.


A female cat is pregnant for an average of nine weeks (65 days). After three weeks, her nipples turn pinkish red, after which it takes another six weeks for the animal to give birth. Weight gain averages one kilogram.


Contractions begin about six hours or more before delivery. The cat begins to breathe faster and purr. The contractions increase from every half hour to every 15 seconds. Then the first kitten will emerge. The female cat will then bite the umbilical cord and start licking the kitten in order to initiate breathing. It is important that the kitten drinks from the colostrum, the first milk.


A young kitten is called a kitten. About 66% of kittens come into the world with the head first. At birth, a kitten is deaf and blind. After about 10 days, a kitten can see, and after 17 days, hearing works. After four to five weeks, a kitten switches to solid food. This is also the time when the mother cat teaches the kittens to use the litter box. Still, many kittens continue to suckle with the mother until they are at least about 6 months of age, if given the chance.

The table below shows the development of a kitten.

1 weekEyes open, beginning of focus
2 weeksCan crawl but not yet stand on legs
17 daysCan hear
3 weeksStarts walking
4 weeksStarts solid foods
6 weeksEyes begin to develop definitive color
8 weeksHas complete deciduous teeth
8 weeksHunting technique is practiced
8 weeksCastration possible
9 weeksFirst vaccination panleukopenia and rhinotraceitis/calici
13 weeksSecond vaccination
18 weeksChanging milk teeth to permanent teeth
24 weeksStandard age castration

In the cat’s childhood, there is a period, between the 12th and 60th days, when cats are open to impressions and lessons. This imprinting period is crucial to the behavior of the adult cat. If the cat has not known people during this time, it will be difficult to socialize.

If a mother cat finds the chosen safe nesting place not safe enough, she may occasionally take the young to another place. This she does instinctively. In the process, the young are carried by the neck muscle. A reflex also present in adult cats ensures that the animals are then completely relaxed.

Nowadays, most kittens are taken to their new owners around 8 weeks of age. Legally, kittens may be taken away from their mother at 7 weeks of age. However, it is advisable to leave the kittens with the mother much longer, especially until they are about 15 weeks old. By that time, the kittens have been vaccinated twice and their natural resistance has been sufficiently built up.



Some substances that are toxic to humans only in high doses can be harmful to cats at low concentrations:

  • Alcohol
  • Caffeine
  • Chocolate
  • Pine oil, causes abdominal pain and organ disorders
  • Essential oil, leads to internal injuries when ingested and causes skin irritation when in contact with skin
  • Lily, cause kidney failure
  • Macadamia nuts, causes muscle tremors, paralysis, joint stiffness and high fever
  • Paracetamol, unlike humans, cats have no enzyme that converts paracetamol to its harmless, excretable metabolite. Even the smallest amount can lead to fatal, irreversible liver necrosis.
  • Tobacco, harmful to nervous and digestive systems, tobacco smoke can lead to malignant lymphomas.


A number of internal and external parasites can be harmful to a cat’s health:

  • Coccidia
  • Giardia lamblia
  • Heartworm
  • Tapeworms
  • Ear mites
  • Roundworms
  • Ticks
  • Toxoplasma gondii
  • Fleas
  • scabies is also a zoonosis


In addition to pedigree domestic cats, there are about forty bred cat breeds. A classification can be made according to origin. Some cat breeds are original phenotypes that have their own appearance with which they have been present in a certain area for centuries, others have been developed through crossbreeding or created by mutations. Each breed has a specific appearance and character. Someone who engages in breeding pedigree cats as a hobby registers them under their own cattery name with an association.

Colors and patterns

There are many colors and patterns in the cat. It is striking that unlike many other animal species the pigments eumelanin (black) and feomelanin (red) are located on the X-chromosome. As a result, cats showing both colors (“patch cats” colloquially) are always female. The rare males that show this color variety are usually of genotype XXY (Klinefelter’s syndrome) and are usually infertile. Furthermore, there are many other color and pattern genes such as dominant white (W), partial white in the coat (S), an aguti gene (A), a number of tabby patterns (Ta/T/tb) (“cypers” colloquially), a gene that decolorizes the underside of the hairs (I, silver effect) and partial albino genes (cs and cb), which are responsible, among other things, for the “siamese coloring” seen only on the extremities of the body. The different genes in combination create a wide palette of combined coat patterns and colors.