Among mammals, felids are one of the families showing higher size variability. Black Footed Cat (Felis nigripes), a species distributed from Namibia and the Kalahari to Cape Province in South Africa, weighing between 1 and 2.5 kg, is more than 100 times lighter than a male Siberian Tiger (Panthera tigris altaica), which may exceed 300 kg.
These size differences help to intuitively understand the felids’ subdivision into two main groups; 1) subfamily Pantherinae, grouping the big cats into two genera (Neofelis and Panthera) and seven species: Clouded Leopards, Snow Leopard, Tiger, Lion, Leopard and Jaguar and; 2) subfamily Felinae, with more than 30 species os small and not so small cats, such as four Lynx species. Among Felinae, just the Cougar (Puma concolor) and the Cheeta (Acinonyx jubatus) are bigger than lynxes, while the Serval (Leptailurus serval), the African Golden Cat (Caracal aurata) and the Caracal (C. caracal) have similar sizes to genus Lynx. By the way, though the Caracal is externally quite similar to a lynx, it is not closely related to them.

The Iberian Lynx is a spotted carnivorous that lives in scrublands, cleared forests and similar habitats of the Mediterranean domain. However, 600,000 years ago, it reached southern France, where some fossils have been found in recent decades. Its distribution even reached Italy, where hundreds of remains more than 40,000 years old have recently been discovered at the Ingarano site near Foggia in southwestern Italy.
Unlike the Iberian Lynx the other three lynx species have wide distribution ranges: the Red Lynx or Bobcat (L. rufus) lives in a wide variety of habitats from central of Canada to northern Mexico, Canada Lynx (L. canadensis) is distributed throughout the boreal forests of Canada and northern USA and the boreal Lynx (L. lynx) lives in the deciduous, mixed and coniferous forests of Europe and northern and central Asia.
The four lynx species form a coherent group that share several common physical characteristics such as short tails, ears with a tuft of long hairs at their tips (known as brushes) and beards. However, their body sizes are the result of each species' adaptations to its habitat and diet, ranging from the 6 kg on average of the bobcat, the smallest of the four, to the Boreal Lynx, which can reach 30 kg.

A common ancestor for today's four lynx species.
Scientists postulate that the the group's ancestor diverged about six million years ago in regions of North America and subsequently spread throughout Eurasia. The Bobcat diverged early from the common ancestor, while the other three species appeared about 1.8 – 2 million years ago.
As in many other known cases, glaciations in Eurasia and North America seem to play an important role in the speciation process of lynxes, and thus, through fragmentation and isolation, the Boreal Lynx in Asia, the Canadian Lynx in America and the Iberian Lynx in the Iberian Peninsula emerged in the Lower Pleistocene. The Iberian Lynx is a medium size strict carnivore. Its average weight is around 12.5 kg. There are significant differences between males and females (with deviations from the mean of up to 3 kg for each sex), males being the largest. Their average length of about 80 cm and their height at the withers of about 45 cm give them a graceful appearance.

The Iberian Lynx is a medium size strict carnivore. Its average weight is around 12.5 kg. There are significant differences between males and females (with deviations from the mean of up to 3 kg for each sex), males being the largest. Their average length of about 80 cm and their height at the withers of about 45 cm give them a graceful appearance.
Its most striking characteristics are those already described as general to lynxes: brushes, beards and a short tail with an apical black tassel. It also has other characteristics typical of felines: striking frontal eyes, which provide precise distances measuring, typical of short-distance hunters; big eyeballs for low light conditions; hirsute, triangular ears for a sharp hearing capable of detecting the discreet walking of the rabbit's fur-insulated feet; disproportionately large hands, useful for firmly grasping its prey, with sharp claws (always sharp because they are retractable) to prevent it from escaping.
Its striking high rump, as the result of its long hind legs, allows very advantageous jumps when hunting.
Its dentition is that of a strict carnivore, with large canines for the fatal blow, molars for tearing up large pieces of meat and small incisors. The dental formula is 3.1.2.1/3.1.2.1.
Basic biometric data of adult Iberian Lynx obtained in LIFE project's sanitary assessments of the (only for specimens over three years of age):

Finally, the spotting of its coat allows it to blend with the scrubland's shades. The varieties of its coat are usually grouped into “thick spots", “medium-sized spots", and “thin spots". Actually, the tendency to define and narrow down everything observed leaves undefined a varied gradation between the two extremes, ranging from large patches, which in some specimens are even lined up as stripes on an orange background, through different sizes of spots, to mottled coats, with such thin spots that they are almost unnoticeable in brown or greyish-brown coats. Although all phenotypes have historically been present in all subpopulations, in Doñana there have only been specimens with thick spots since the 60s of the last century, the consequence of allele fixation caused by a “bottleneck" in which the few specimens that survived had this phenotype. However, the higher genetic variability conserved in the Sierra Morena subpopulation has allowed individuals with all types of coats. In 2007, an individual was moved from Andújar to Doñana-Aljarafe to start the genetic reinforcement of this population. In the spring of 2008, the first native medium-size-spot cubs resulting from gene mixing could be seen in the receiving population. Currently, all the existing subpopulations of the feline in the Iberian Peninsula have specimens with the full range of spotted coats.

This feline is what is known as a habitat and prey specialist. And despite its broad food spectrum, the rabbit is its main prey and constitutes around 90% of its diet. The biology of rabbits, dependent on shelter and grazing areas, means that when the lagomorphs come out to feed, the lynx can arrive unseen and unheard and catch its prey. This extreme specialisation makes it very successful in places where these requirements are well represented, but it has also been the cause of its decline. The disappearance of well-preserved habitat, the drastic decrease of rabbit populations, and direct human persecution, brought the Iberian Lynx to the brink of extinction.

Adult lynxes live in territories that may overlap to a large extent with adult lynxes of the opposite sex and, to a lesser extent, with those of the same sex. The average size is around 600 ha, but there are much larger territories in low-quality areas with lower rabbit densities. Territory occupation occurs 1) through a vacancy due to the disappearance of a territorial animal, 2) through a dispersing lynx winning a territorial lynx's space, or 3) through the occupation of improved previously-unoccupied areas.
Females can breed from the age of two years, although they tend to do so when older, usually because they haven't been able to establish themselves in a territory of their own. Lynxes come into oestrus once a year, although some years, females do not get pregnant or fail to raise cubs. It is common for some sub-adult young (mainly females) from the previous year's litter to remain and help raise new cubs from their mother's litter. Sometimes mother and daughter share territory for years, splitting up (if the quality of the habitat allows it) or the older animal leaving, probably expelled by the younger if the rabbit densities in the area do not allow the reproduction of both females.

All wild animal species have perinatal mortality; that happening during pregnancy and the first days after birth. It is difficult to determine the actual causes of perinatal deaths of the Iberian Lynx. It is also difficult to know how many pregnant females lose their cubs before, while birthing or even during the first weeks of life. The ex-situ conservation programme gives us information in this sense, but the physical conditions of wild females are different from those in captivity.
In a high percentage of the litters with three and four cubs monitored in the last decades only two cubs survived, with a first mortality peak during the first month of life and a second one around the third-fourth month. Predictive models developed by EBD showed a very small effect when extracting cubs from litters with more than two, so some cubs were extracted and brought into the ex-situ conservation breeding programme. However, just a few newborn cubs have been managed this way because it is very difficult acces dens without disturbing the female.
Cub survival is closely related to prey abundance in the female’s territory. With the species’ range growth, due to the reintroductions started in 2009 and the recovery plans of the different regions involved in the conservation of the species, there have also been more numerous litters, with five or six cubs in areas with high rabbit densities.

Before starting the captive breeding programme, a second mortality peak was observed in wild cubs around three months old. The ex-situ conservation programme observed in the firsts litters in captivity that at that age cubs develop an extreme agressive behaviour when playing with their siblings, and that although mothers play a decisive role separating their cubs, some plays can be lethal. In captivity mothers are always close to their cubs, while this situation may be different in the wild.
It is very likely that the mother's absence while hunting favours lethal sibling fights during excessively aggressive hunting-training plays. There are some cases of cubs in their aggressive age found with signs of fighting, such as Cromo, which was incorporated into the captivity breeding programme.

The confrontation between residents and dispersing lynxes usually is the only way for the latter to get a territory of their own. Clashes between males are worse when the females are on heat, as males try to mate with as many reproductive females as possible. Sometimes confrontations end with the death of one of the males due to the injuries received during the fights. Deaths during these clashes are unusual because most of the times threats are enough to resolve the encounters. Dispersing lynxes are well aware of which territories are occupied as resident lynxes mark their territories with urine and scats, but when there is an unoccupied patch of suitable habitat, extremely aggressive situations can arise.

In recent years, thanks to the high percentage of lynxes radio-tagged in Iberian Lynx-related LIFE projects, we have known about some cases of long-distance dispersals of old lynxes (around nine years old) that, after having spent their whole adult life in the same territory, are displaced and move to suboptimal areas, sometimes through very long dispersal movements. Years ago, when a non-radiotagged animal went missing, the disappearance was attributed to its natural death. Now we know of radiotagged lynxes that have dispersed over long distances, staying alive for months or even years in other territories. These senile animals are intensively monitored to detect possible births and to better understand how valuable they are in the creation of new territories and to settle new individuals in their surroundings.
Deaths by old age in wildlife are usually caused by wear and tear of the organism, with associated pathologies, low response capacity of the immune system or degenerative diseases. Just a few Iberian Lynx deaths of this type have been confirmed because it is hard to find non-radiotagged carcasses. Usually, these natural deaths occur in suboptimal peripheral areas, where old animals have been displaced by more vigorous animals. However, the fact that each year more 10-12 years-old individuals are detected is excellent news, as it suggests a general decrease in the species’ mortality, particularly in the adult population, the reproductive and more valuable age period.

Apart from the indirect signs of lynx presence shown in the photographs, traces of dragging prey, tracks and droppings, the Iberian lynx is one of the carnivores most easily seen in the wild. They are very active during the day if the weather is not too warm, and they aren’t very shy due to their ecological role as superpredators (with few enemies in the wild). When a lynx is settled in a territory it is easy to find tracks and latrines, and is regularly observed by the local population.
Dispersing specimens (both juveniles and senile) may go unnoticed, as they do not form latrines or other specific marking systems on their movements (which can be up to 25 km per day). The presence of the Iberian lynx in an area is easily detected. Iberian lynx’s territorial marking is based mainly on urine and faeces, some of these marks being very conspicuous.
Although urine marks are not detectable, Iberian lynxes form many latrines in their territories, warning conspecifics of their ownership. The latrines size is variable, but apparently, they are larger where territories of several individuals overlap. In addition, lynx tracks, characteristic of felines, are easily identifiable on suitable substrates.