Kzinti evolved from a plains-hunting
felid, on a planet slightly colder and drier than
Earth. The Kzin word for their home planet translates as Homeworld, often known as Kzinhome, among the Kzinti themselves. It is the third planet orbiting the star
61 Ursae Majoris. The Kzin civilization was at an iron-age technological level, when an alien race called the
Jotoki landed, and made stealthy
first contact with a tribe of primitive hunter/gatherer Kzinti: they were interstellar merchants, looking for a species they could use as mercenaries. Once the Jotok had taught the Kzinti how to use high-tech weapons, and other devices (including spacecraft), the Kzin rebelled, and made their former masters into slaves -- as well as the occasional meal. The crest of the Riit (Royal) family appears to be a bite mark -- though it is in fact a
dentate leaf, with the words "From mercenary to master.", written around it in Kzinti script. Kzin society is extremely male-dominated. The leader of the race is called the
Patriarch, and is a hereditary title. The Kzinti call themselves "heroes" or the "Hero Race", and because they believe themselves to be "heroes", their society places a very high value on "acting Heroic", and behaving in a heroic fashion. To Kzin society, "heroic" means being honorable, and having integrity. Kzin honor, called
strakh, is similar in many ways to the
samurai code of
Bushido.
Strakh serves as almost a sort of currency or favor system, since their culture has no analog for money. For example, if the Patriarch gets meat from a seller's market stand, the seller gains considerable
strakh, which will bring honor to the seller, aiding him to attract better customers, gaining
strakh, i.e. higher status within the community. Once Kzinti gained access to genetic-manipulation technology, they used it to reinforce and intensify their species' most "heroic" qualities and reduce the undesirable ones. To this end -- and because females are not valued except as bearers of children -- the male-dominated Kzin society bred (most of) their own females into sub-sapience. Kzinti are often described as "anthropomorphic tigers," but there are significant, and visible, differences. Kzinti are larger than humans, standing around tall, and weighing around . These tiger-sized
bipeds have large and membranous ears, a barrel-chested torso, with a flexible spine, and large fangs and claws. One human gave an apt description of Kzin as "eight feet of death." Unlike some popularly depicted anthropomorphic animals, Kzinti stand on two legs as do humans; they lack
digitigrade ("backward-bending") legs. Hands have three fingers and an opposable thumb, each with a retractable claw. Kzinti are covered with a thick coat of long fur, which comes in various combinations of orange, yellow, and black. (Full black coats are rare.) Their tails are naked, and similar in appearance to a rat's tail; their noses are black. Kzinti ears have fur, but only on the outside of the ear, and only about halfway up the ear itself, usually appear pink, and are shaped like a segment of a Chinese
parasol (or
cocktail umbrella; they are also sometimes described as "bat-winged"). They can fold back flat against the head for protection during a fight. Kzinti speak in a hissing language they call the ''Hero's Tongue'', which in its written form resembles
commas and
periods. Kzinti cubs are tested by the Black Priests. Females are tested for intelligence; those who fail their tests by revealing too much intelligence are killed. Males are tested for telepathy; the ones who exhibit telepathic ability are forced into addiction of a drug derived from the lymph of an animal called a
sthondat, which significantly increases
telepathic ability. However, it is addictive and toxic, with long-term use, causing muscle atrophy, and thinning fur. The black-fur gene and the telepath gene are mutually exclusive; no completely black-furred Kzin is telepathic. All such cubs are taken by the Black Priests and raised within their cult. Telepaths are tolerated by the warrior class, due to the specialized use of their skill; otherwise, they endure a low-
caste position in society, just above the status of slaves; a slave is occasionally considered of a higher social status. Telepaths rarely, if ever, earn a name, and they are legally forbidden to breed. Most Kzin females (
s. Kzin
rret,
pl. Kzin
rretti) are sub-sapient, with a vocabulary of fewer than a hundred word/sounds, and primarily instinct-driven behavior, and are treated as
chattel by males. (
s. Kzin
tosh,
pl. Kzin
toshi) This was not always the case: archaic Kzinrretti were sapient, until the Kzin used
Jotoki biotechnology to reduce them to their current state, and also boosted the martial prowess in the males. Kzin society explains this, by stating that the (perhaps male?) Fanged God removed the Kzinrretti souls, as punishment for an attempted rebellion against him, shortly after he created the Kzinti. Nevertheless, even by the period of the novels, certain bloodlines still produce sentient females (as do some, if not most, primitive tribes). These tribes, long isolated from the patriarchy, avoided genetic modifications; at least two sentient females exist on Wunderland, and a population also exist on the Ringworld. In the
Known Space universe, the Kzinti are the first ongoing alien contact that humanity has met. The
first contact with humanity ends the human
golden era of peace -- where even history has been rewritten with a non-violent whitewash; organized violence was virtually eliminated, being reduced to roughly 1 in 1000 people, and interpersonal violence was unknown, except for occasional outbursts in the
asteroid belt, where both medical and psychological care were thinly spread. ==Naming convention==