Until recently, zoologists often classified the smaller species of modern cats together in the single genus Felis, with the big cats usually kept separate as species of the genus Panthera and the cheetah in its own genus, Acinonyx. Much of this classification system has been changed based on DNA work and other genetic studies that suggest a complex history that separates living members of the cat family into eight distinct lineages. Many cats formerly classified as species of Felis do not have the same common ancestors and so are not grouped together. Nonetheless, hybrids between different species of cats are often fertile and can produce fertile offspring.
The eight cat lineages branched from each other at different times over the past 11 million years as the ancestors of modern cats spread from Asia to different parts of the world. Ancient changes in sea level created temporary land links that allowed cats to cross between continents and regions now separated by water. In other cases, sea levels that were as high, or higher, than today separated groups of cats. Both migration and separation affected cat evolution. Most notably, some types of cats that evolved in the Americas from Asian ancestors later migrated back into Asia. Examples include the cheetah—which spread from North America to Asia, and then to Africa—and the lynx—which spread from North America into Asia and into Europe.
The different types of living cats belong to the following groups:
| VIII | Cat Family Members and Humans |
| A | Ancient Relations with Cats |
The ancestors of humans lived alongside big cats and saber-tooths for millions of years. Early hominids were likely prey for big cats and other large predators. However, hominid species may have scavenged kills made by big cats and their saber-toothed relatives. Hominids could use stones to crack open large bones for marrow, a rich food source not easily available to cats. According to some theories, scavenging of predator kills may have provided a food source that helped early forms of humans spread out of Africa into Asia and Europe around 1.8 million years ago.
The earliest direct evidence of how modern humans (Homo sapiens) viewed members of the cat family comes from cave art. Drawings of lions dating to 32,000 years ago were found in 1994 in a cave in Chauvet, France. Lion images carved from mammoth tusk ivory that were found in Vogelherd caves in Germany may be even older. Curiously, no lions shown in ice age art from Europe have manes, suggesting ancient European lions lacked this feature.
Images of these formidable predators may have had some spiritual or religious significance for early humans since lions were likely not hunted for food. Later cultures worshipped cats as powerful spirits or representatives of gods. The domestic cat and the lion represented the gods Bast and Sekhmet in ancient Egypt. The jaguar was an important deity or spirit to many Pre-Columbian peoples in the Americas, as was the lion among African peoples, and the tiger in parts of Asia.
| B | Domestication, Hunting, and Captivity of Cats |
The most important event in relations between humans and cats occurred around 12,000 to 10,000 years ago when a small wildcat began to associate with early human settlements in the Fertile Crescent region of the Middle East. As humans adopted agriculture, stored grain and other food products attracted rodents and other pests that became ready prey for the local wildcat Felis silvestris libyca.
Over time some of the wildcats gave up their more aggressive wild behavior to adapt to life alongside people. Humans found the cat a useful animal to control vermin and an enjoyable companion as a pet. DNA from living cats shows that all modern domestic cats around the world are descendants of five females of this wild Middle Eastern subspecies according to research published in 2007. Prior to this DNA study, many experts thought that cats were first domesticated in ancient Egypt around 2500 bc.
Other wild members of the cat family have been adopted as pets or kept in captivity for thousands of years. Royalty in Egypt, Persia, and India used cheetahs for hunting as a sport. In ancient Rome, gladiators fought lions and tigers in arena games. The Romans also used big cats and other wild animals to kill condemned prisoners in public spectacles. During the Middle Ages, royalty in Europe sometimes kept captive lions. Big cats have been symbols of royalty in many cultures: lions in Europe and in Africa, tigers in Asia, and jaguars in Central and South America.
Members of the cat family have long been hunted to protect livestock or human populations. Cats have also been hunted for sport and for the fur trade. The pelts of spotted cats such as leopards and ocelots have been particularly valued. Body parts from tigers, leopards, and other cats have been used in traditional medicine and in magic.
In the modern world, many types of cats are displayed at zoos or at wildlife farms. Trained lions and tigers perform in circuses or in stage shows. Some people keep wild cat species as exotic pets, often raising them from the cub stage. However, owners are sometimes forced to give up their pets when the animals are fully grown and become difficult to control or maintain. Special ranches have been established as sanctuaries to care for big cats once kept as pets or retired from zoos or circuses. More controversial are ranches where exotic cats can be hunted and killed for a fee. Also controversial are tiger farms in Asia that raise tigers to be slaughtered for body parts used in traditional medicine.
| C | Scientific Study |
Scientific study of cats in the wild has made major progress since the 1960s. At one time, cats had to be monitored visually in daylight, or they were captured and tagged, then recaptured. Radio-tracking of pumas, lions, leopards, and other large cats became widespread in the 1970s. An animal was usually darted with tranquillizers then fitted with a battery-powered radio-collar that would send out signals that could be used to track the cat’s movements remotely. Recently, links to global positioning system (GPS) satellites have provided much more precise information about the locations of radio-collared cats.
Other methods of studying cats in the wild include installing still-cameras on trails or paths used by cats. The camera photographs any passing animals. Light-intensifying and infrared motion-picture cameras allow researchers to study and record the night-time activities of cats without using spotlights. Some cats have even been fitted with special cameras called “crittercams” to record behavior from the cat’s point of view. Cells isolated from droppings (called scat) and shed hair can provide DNA and other genetic information, including how cats in a given area may be related to each other.
| IX | Conservation Issues |
Some members of the cat family are at a high risk of extinction in the wild and are listed as endangered by the World Conservation Union (IUCN). The most endangered cats include subspecies that have very small populations such as the Spanish lynx, the snow leopard, the Amur leopard, the Arabian leopard, the Asiatic cheetah, and the Asiatic lion. The puma subspecies in Florida known as the Florida panther is also highly endangered. Tigers are endangered in nearly all areas where they are found.
Other members of the cat family are listed as vulnerable by the IUCN, meaning they could be threatened with extinction in the future if conditions change. Leopards over much of their range, cheetahs in Africa, clouded leopards, and jaguars fall into this group, along with some species of smaller cats. The International Convention on Trade in Endangered Species (CITES) lists cats and cat-derived products that cannot be exported or require special permits.
Major threats to cats include loss of habitat from deforestation, and from expansion of farm lands and urban areas. Cats may lose their natural prey and be forced into smaller and smaller territories to find food and shelter, bringing them into contact with humans. Lions, leopards, and cheetahs that attack domestic animals can be shot legally in many African countries. Diseases such as distemper have been spread from domestic dogs living near parks in Africa to lions and other wild predators.
As populations fall, inbreeding and lack of genetic diversity can become a problem, making affected cat populations more susceptible to disease, infertility, and physical abnormalities. Illegal hunting or poaching for pelts, meat, and body parts also takes a heavy toll on some cats such as tigers and snow leopards.
Conservation groups devoted to saving cats include the Cat Specialist Group (CSG), the Small Cat Conservation Alliance, and the Cat Action Treasury (CAT), as well as the Cat Survival Trust, Project Tiger, and the International Snow Leopard Trust. Activities include establishing parks, reserves, and other protected areas for cats in the wild. Additional approaches include zoos and special facilities where endangered cats can be protected and bred in captivity. Conservationists and biologists have reintroduced some cat species such as the cheetah, the ocelot, and the lynx back into areas where they previously lived but had disappeared.
Scientific classification: Cats make up the family Felidae, of the order Carnivora. The tiger is classified as Panthera tigris, the lion as Panthera leo, the jaguar as Panthera onca, and the leopard as Panthera pardus. The mainland clouded leopard is classified as Neofelis nebulosa, and the cheetah as Acinonyx jubatus. The Canada lynx is classified as Lynx canadensis (formerly Felis lynx), and the bobcat as Lynx rufus. The ocelot is classified as Leopardus pardalis (formerly Felis pardalis), the pampas cat as Leopardus colocolo (formerly Felis colocolo), Geoffroy’s cat as Leopardus geoffroyi or Oncifelis geoffroyi (formerly Felis geoffroyi), the kodkod as Leopardus guigna (formerly Felis guigna), the little spotted cat or tigrina as Leopardus tigrinus (formerly Felis tigrina), the margay as Leopardus wiedii (formerly Felis wiedii), and the Andes mountain cat as Leopardus jacobita (formerly Felis jacobita). The puma is classified as Puma concolor (formerly Felis concolor) and the jaguarundi as Puma yaguarondi or Herpailurus yaguarondi (formerly Felis yaguarondi). The wildcat is classified as Felis silvestris and the domestic cat as Felis silvestris catus.
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