This relic representative of feline family is the large prey hunter. It is possible to guess it easily, having looked at the constitution of animal - this predator is not similar to cheetah or leopard chasing swift-footed catch. Body of sabertooth is very massive: this is a tiger-sized animal (weighting about 350 kgs), but its figure resembles bear more: legs are thicker with wide pads (animal began almost plantigrade one). Back legs are a little bit longer than front ones, back is inclined forward. The short tail has got to this animal as the inheritance from the ancestor. Wool colouring is sandy-yellow with dark-grey spots, to winter it changes to white with ashy shade (this phenomenon is the exception among cats not changing color of wool in winter), stains on winter fur completely disappear. The winter wool is much longer and also thicker than summer one: it is the adaptation to life in conditions of continental climate of Northeast Asia with rigorous snow winters.
Siberian sabertooth is the tireless nomade of open spaces of Siberia and Beringia. This animal literally “pastures” herds of large herbivores, following them during migrations. The most important catch of an animal is obda, huge herbivorous animal of Siberia. For hunting for this giant sabertooth uses tactics of attack from ambush, but it frequently avowedly attacks animals kept up with herd. Predator attacks catch sideways, striking during the throw by one paw on shoulder, by another one – on head of prey. Usually young or weak animal falls aside, and it is easy for finishing off by bite in throat. At the sting canines of sabertooth pass below backbone (in other way they simply can be broken) and break off blood vessels and trachea of prey. If the chosen prey is strong enough, predator simply wounds it by bite and follows herd, expecting while wounded prey will get behind neighbours, bleeding profusely. One carcass of obda suffices to the predator in summer time for one week - while meat will deteriorate to the uneatable condition. In winter when meat is better kept, the preied animal suffices approximately for two weeks. But more often such catch should be divided with set of feathered and four-footed scavengers; therefore sabertooth had to hunt more often. One animal theoretically should supervise territory 200 - 300 square kilometers, but it leads nomadic life, therefore sometimes “shepherds” of different obda herds meet on summer pastures of these animals. At this time pairing and birth of cubs concepted the last year happen. At summer obda pastures sabertoothes sometimes unite for hunting, together getting the next dinner.
Pairing of sabertoothes occurs at the end of summer shortly before leaving of obda herds to the south. The female ready to pairing calls the male by sounds similar to loud bass mewing. Usually near such female two - three males keep but only choosed by female one can couple with her. Between males there are skirmishes during which contenders beat each other by paws and show force, peeling bark from trees. Males ready to pairing also mark by urine tree trunks – smell plays the important role for the female in choice of the partner. When pair is formed, male and female banish single males together. Pairing at these cats repeats many times during three or four days while the female is ready to accept attention of the male. At this time the male looks after her, licking her wool. He also marks a site of wood around female with urine to warn contenders, that the present female is occupied. During courtship games animals eat of nothing. After pairing the female walks out from the territory marked by male.
Pregnancy at this species proceeds a long time: more than nine months. The reason of it is that fertilized oosperm does not develop at all about half-year. Development of embryos begins approximately at first half of winter, and actually proceeds little more than three months. Cubs are born just when the female comes to the north after wintering in woods.
For birth of cubs the female sabertooth makes a lair under roots of trees or among stones. In pack there are two or three cubs. Newborn sabertoothes are covered with dark-brown wool on which stains are already appreciable. At them eyes and ears are closed, and first two weeks of life they are absolutely helpless and completely depend on mother. Within four months, before autumn obda migration cubs grow and develop quickly. At this time they actively study to hunt, accompanying with mother. During migrations behind obda herds sabertooth cubs remember district, and later, becoming independent, begin “shepherd” herds.
Young growth stays with mother up to one-year-old age. When families come to northern obda pastures again, young animals leave mother and start to hunt independently. Sexual maturity at young females comes at the second year of life, at males at the third year. Life expectancy can reach 40 years.
In east areas of Northern America Siberian sabertooth is replaced by close species of easier constitution – Nearctic sabertooth (Machairolynx nearctica), or missopeho (named after giant lynx of the North, the hero of Indian folk tales). At this animal canines are shorter; colouring is lighter and does not vary for winter. Constitution of Nearctic sabertooth is more graceful: legs are longer, size of body is less. It is connected with specialization to feeding by smaller swift-footed prey. As against to Siberian sabertooth, these species is settled and territorial.