Felids are perhaps the most specialized hunters of the carnivores, relying almost exclusively on prey that they have killed themselves. Their distribution includes every continent except for Australia and Antarctica, with the exception of the domestic cat which has now been transported to just about everywhere humans have gone. Cats are also not native to the island of Madagascar. Felids use a diversity of habitats, from desert to forest to mountain.

 

Physical features characterizing felids are a short rostrum, a vestigial or absent baculum, and retractable claws. Distal segments of digits in the relaxed position are pulled back and up into a sheath by an elastic segment, which prevents claws from getting blunt. The cheetah is an exception; it cannot retract its claws, and when attacking it tends to bowl over prey much like many canids. Cats have five toes on their forefeet and four on their hindfeet. They are digitigrade, and their metapodials are moderately long but never fused.

 

Besides having a short rostrum, the skulls of cats have bullae that are large and divided by a septum; no alisphenoid canal, and paroccipital processes flattened against the bullae.

 

Dentition is reduced in felids; shortening the jaw results in increased force at the bite point. The dental formula is 3/3, 1/1, 2-3/2, 1/1 = 28-30. The incisors are small and chisel-like. The canines vary from medium-sized to enormous in the extinct sabertooth cats. The upper canine is larger than the lower. The first premolar is absent; the second, when present, is atrophied. The molar is small and simple in structure. Carnassials are very well developed and cheek teeth are exclusively of the shearing type; cats do not crush or grind their food.

 

The hunting method of felids consists of a preliminary stalk followed by a final quick rush. Cats aim for the neck and usually sever the cervical vertebrae with their sharp, pointed canines. They rely on their sense of sight; their eyes are relatively large compared to other carnivores. They also have well-developed senses of smell and hearing, and at close range, their long whiskers provide an acute sense of touch.

 

Felids are usually solitary. An exception is the African lion, which forms prides centered around maternal descent. Males fight with each other for acceptance into these prides. The size of a lion pride is determined by resource availability. Lion females hunt cooperatively for the whole pride. Males are the main defenders of territories, keeping out foreign males and females. Males are driven from their natal prides at around three years of age and often spend time as nomads before they are able to defend their own pride.

 

The fossil record of the Felidae extends to the Late Eocene. No description of fossil felids is complete without some mention of the sabretooth cats. In these forms (and there were a number of species in at least two lineages of feloids involved), the upper canines elongate tremendously to form stabbing, sabre-like weapons. These teeth curve backward, flatten to become triangular in cross section, and sometimes develope a serrated edge. It seems clear that they are adaptations for stabbing prey, but exactly how they were used remains a mystery.

 

Two species of felids in Michigan, bobcat ( Lynxrufus) and lynx ( Lynxcanadensis), can be distinguished by the shape of their presphenoid and the openings to hypoglossal and jugular foramina in the base of the cranium.

 

    Technical characters 

   

  Literature and references cited 

 

Feldhamer, G. A., L. C. Drickamer, S. H. Vessey, and J. F. Merritt. 1999. Mammalogy. Adaptation, Diversity, and Ecology. WCB McGraw-Hill, Boston. xii+563pp.

 

Paradiso, J. L. 1975. Walker's Mammals of the World, Third Edition. Johns Hopkins University Press, Baltimore.

 

Savage, R. J. G. and M. R. Long. 1986. Mammal Evolution, an Illustrated Guide. Facts of File Publications, New York. 259 pp.

 

Stains, H. J. 1984. Carnivores. Pp. 491-521 in Anderson, S. and J. K. Jones, Jr. (eds). Orders and Families of Recent Mammals of the World. John Wiley and Sons, N.Y. xii+686 pp.

 

Vaughan, T. A. 1986. Mammalogy. Third Edition. Saunders College Publishing, Fort Worth. vii+576 pp.

 

Vaughan, T. A., J. M. Ryan, N. J. Czaplewski. 2000. Mammalogy. Fourth Edition. Saunders College Publishing, Philadelphia. vii+565pp.

 

Wilson, D. E., and D. M. Reeder. 1993. Mammal Species of the World, A Taxonomic and Geographic Reference. 2nd edition. Smithsonian Institution Press, Washington. xviii+1206 pp.

 

The cats. Felids are the most strictly carnivorous of the sixteen mammal families in the order Carnivora. The most familiar felid is the domestic cat, which first became associated with humans about 10,000 years ago, but the family includes all other wild cats including the big cats.  Discounting extinct species, the living felids belong to either the Pantherinae (lion, tiger, jaguar, and leopard), and Felinae (cougar, cheetah, lynxes caracal, and domestic cat).  The first felids emerged dabout 25 million years ago. In prehistoric times, there was a third group called the Machairodontinae, which included the saber-toothed cats such as the well known Smilodon.   There are 40 known species of felids in the world today. They originated in Asia and spread across continents by crossing land bridges. Ancient cats evolved into eight main lineages that diverged in the course of at least 10 migrations (in both directions) from continent to continent via the Bering land bridge and Isthmus of Panama. The Panthera species are the oldest and the Felis species are the youngest.   Felids are purely carnivorous animals, subsisting almost entirely on other vertebrates. Aside from the lion, they are solitary. Most are secretive animals, often nocturnal, and live in relatively inaccessible habitats. Around three-quarters of cat species live in forested terrain, and they are generally agile climbers. However, felids may be found in almost any environment, with some species being native to mountainous terrain or deserts. Wild felids are native to every continent except Australia and Antarctica.  The various species of felid vary greatly in size. One of the smallest is the Black-footed Cat at between 35-40 cm in length, while the largest and most powerful is the Siberian tiger. Compared with many other mammals, they have relatively short faces, and good binocular vision.  The fur of felids takes many different forms, being much thicker in those species that live in cold environments, such as the Snow Leopard. The colour of felids is also highly variable, although brown to golden fur is common in most species, often marked with distinctive spots, stripes, or rosettes. Many species also have a \"tear stripe,\" a black stripe running from the corner of each eye down the side of the nose.  The tongue of felids is covered with horny papillae, which help to rasp meat from their prey. Almost all felids have fully retractable claws (one exception is the cheetah). Cats have five toes on their forefeet and four on their hindfeet, reflecting their reliance on griping and holding down their pray with their claws.  Felids have relatively large eyes, situated to provide binocular vision. Their night vision is especially good, due to the presence of a tapetum lucidum, which reflects light back inside the eyeball, and gives cat eyes their distinctive shine.  The ears of felids are also large, and in the smaller cats especially sensitive to high-frequency sounds. Felids have a highly developed sense of smell, although not as much so as in canids. This is further supplemented by the presence of a vomeronasal organ in the roof of the mouth, allowing the animal to taste the air. The use of this organ is associated with the Flehmen response, in which the upper lip is curled upwards.  Felids possess highly sensitive vibrissa (whiskers) set deep within the skin, and provide the cat with sensory information about the slightest air movement around it. For this reason they are very helpful for a nocturnal hunter. Most felids are able to land on their feet after a fall, an ability which relies on vision and the sense of balance acting together.  The canine teeth are large, reaching exceptional size in the extinct saber-tooth species. The upper third premolar and lower molar are adapted as carnassial teeth, suited to tearing and cutting flesh.  The jaws of felids can only move vertically. This prevents them from being able to chew, but makes it easier for their powerful masseter jaw muscles to hold struggling prey.   Text after Wikipedia, 3rd August 2008.

 

The skeleton of a cat allows it to absorb shocks to its forelimbs because it has no direct skeletal connection between its collarbone and vertebral column.

     
  "Cats have no direct skeletal connection through a collarbone between the bones of their forelimbs (pectoral girdle) and those of their vertebral columns. In effect, they have shock-mounted forelimbs, which cushion a landing after a jump. None of these schemes reduce the extremes of velocity one bit; what they reduce are the velocity gradients." (Vogel 2003:77)
  Learn more about this functional adaptation.

 

The sensory system of cats detects X-ray radiation with the olfactory bulb, rather than the eyes.

   
  "In 1965, a team of biologists at the Veterans Administration Hospital in Long Beach, California, performed experiments that seemed to show that cats could detect X rays. In conditioning experiments, cats reacted to five-second exposures of X-ray radiation in order to avoid a mild rebuff. In attempting to pinpoint the body region responsible for this remarkable feat, the researchers found that the olfactory bulb behind the nasal and oral passages was the most responsive region, rather than the eyes." (Shuker 2001:21)
  Learn more about this functional adaptation.