"The cat family is placed within the order Carnivora, which comprises nine extant families (or ten if mongooses are considered a separate family; Herpestidae).
The carnivores are grouped into two suborders:
--the catlike carnivores, or Feliformia, including the Felidae (cats), the Hyaenidae (hyenas), the Viveridae (civets), and the Herpestidae (mongooses);
--and the dog-like carnivores, or Caniformia, including the Canidae (dogs), the Ursidae (bears), the Procyonidae (raccoons), and the Mustelidae (weasels), as well as two marine families, the Otariidae (sea lions) and the Phocidae (seals).
The earliest cat-like carnivore family, the Nimravidae (paleosabers), includes two lineages that suddenly appear in the late Eocene jungles of North America.
--One lineage, represented by Hoplophoneus, was saber-toothed; the other lineage, represented by Dinictis, was rather like a modern serval. So convincingly cat-like are these fossils that originally they were called paleofelids and designated the first cats.
--The more recent cat family, the Felidae, include the modern cats, Felinae; and the neosabers, Machairodontinae, e.g. Smilodon.
The Nimravidae-Felidae ‘two-family’ hypothesis is supported less by ossifications and more by phylogenetic considerations; specifically, that the Felidae arose from Proailurus during the Miocene in the Old World. Proailurus, the animal currently nominated the first ‘true’ cat, was short, only 15 cm in length.
The next most recent cat, Pseudaelurus, had a clearly cat-like skull, based on its general morphology and dentition. It roamed Europe and North American during the Miocene. Several different forms of Pseudaelurus existed and these are believed to have formed the basis for the later radiation and diversification of the neofelid cats and the sabre-tooth tigers. Proailurus, from the Miocene, is the reason why New World paleosabers from the Eocene cannot be cats. As a result the origins of the paleosabers have had to be placed elsewhere; e.g. within the dog-like carnivores or even outside the carnivores. It is easy to see how the two-family hypothesis could be specious, based on preconceived notions.
in point is the early attempt to separate small cats and big cats into separate subfamilies based on ossifications in their hyoid apparatus and their ability to roar. Sir Richard Owen was the first to explore hyoid anatomy and felid vocalization. The hyoid apparatus consists of two chains of seven bones, joined at the fifth (basihyoid). These stretch from the auditory bullae to the larynx, support the voice box, and confer characteristic vocalizations.
--In small cats (the felines) the third bones (epihyoids) are ossified and short, and they cannot roar.
--In the larger big cats (the pantherines) the third epihyoids are cartilaginous and extended, and all but one of these cats can roar. In snow leopards the epihyoids are cartilaginous; however, they still cannot roar because they lack additional pads in their vocal folds.
Only in the extant clouded leopard (Neofelis nebulosa) can a vestige of the saber tooth phenotype still be observed; although both the upper and the lower canines are pronounced, this is a unique occurrence in the cat family. Why these animals became extinct is something of a mystery. These large carnivores would have required large prey; saber teeth are inefficient for capturing and killing small prey. Biome change may have led to an imbalance in predator–prey relations, resulting both in the loss of sustainable populations of large prey and in the extinction of these remarkable cats.
indicating that the original cat family coat pattern was actually small spots or ‘flecks’. This is highlighted by changes observed in pelage patterns of jaguars and leopards during their development. Juveniles possess a simple spot pattern but adults display a range of complex rosettes. A recent theoretical study by Liu and colleagues, using mathematical models, confirmed that in both the jaguar and leopard a single mathematical function (based on a Turing-Model) could simulate both the simple fleck-pattern of juveniles and the complex rosette-pattern of the adults. It appears that differences in pelage patterns can be traced back to subtle variations of the basic pattern. These can adequately explain the changes observed during both the development of individuals and the radiation of cat lineages.
In other words, mechanisms of change such as recombination and natural selection appear sufficient to explain the variation in melanistic spot patterns observed within the cat family. Other patterns like the stripes of the tiger were not investigated in the study, but the same kind of mathematical modeling has been used to simulate formation of stripes in other animals.
Whole coat melanism in the domestic cat, jaguar and jaguarundi has been elucidated at the molecular level. These pelage pattern studies seem to reinforce the general observation that cats form a unique and well-defined group of animals.
F. lybica is easier to tame; it is far less shy of man.
Because domestic cats have a smaller adrenal gland, less epinephrine is produced and the animals are much quieter than wild cats.
These studies parallel observations by Trut et al. in studies of fox domestication. Together the studies suggest that the domesticated phenotype lies dormant within the genetic potential of many wild species.
A recent extensive study of mitochondrial DNA sequences from hundreds of domestic and wild cats across Europe, Asia, and Africa (including the domestic cat (F. catus), the European wildcat (F. silvestris), the African wildcat (F. libyca) and the Chinese desert cat (F. bieti), using the desert (sand) cat (F. margarita) as an outgroup, has clarified with great certainty the various ancestral relationships.
In addition, the domestic cat, the European wildcat, the African wildcat, and also the Chinese desert cat all appear to belong to a single species. Cementing this idea is the fact that mitochondrial DNA from domestic cats is routinely found in all three wild cat populations. Natural hybridizations between them are frequent events.
These include: P. leo × P. tigris (Liger or Tigon), P. leo × P. pardus (Liard or Leopon), P. tigris × P. pardus (Tigard).....Female hybrids of lions and tigers are fertile and reproduce. Their offspring also enjoy a clear nomenclature. Li-ligers, li-tigons, ti-ligers, and ti-tigons are all readily bred from female ligers and tigons, and the female offspring of these crosses are also fertile.
P. concolor × L. pardalis (puma × ocelot) bridges the gap between larger and smaller cats. --Hybridization data connects the largest cats, P. tigris and the massive Liger (400+kg), to the smallest cat, F. nigripes, via seven documented hybrid steps:
P. tigris (110–320 kg) × P. leo (120–250 kg) × P. pardus (30–85 kg) × P. concolor (35–100 kg) × L. pardalis (11–16 kg) × L. wiedii (3–9 kg) × F. catus (3–7 kg) × F. nigripes (1.5–2.5 kg).
Intralineage hybrids of the lynx always involve the bobcat (L. rufus) and are referred to as Blynx or Lynx cats. Five cat hybrids are bred commercially as pets: F. chaus × F. silvestris (Euro-chaus), L. rufus × F. chaus (Jungle lynx), L. rufus × F. catus (desert lynx), F. catus × P. bengalensis (Bengal cat), and Bengal cat × F. chaus (Jungle bob).
37 felid species. At least four FIV strains are species-specific. However, it also infects Crocuta crocuta (the spotted hyena) a member of the felids’ taxonomically closest family. Nevertheless, the studies confirm that FIV transfer, even between cat species, is an infrequent event.
The deadly viral disease, Feline Infectious Peritonitis (FIP), is specific to cats. Its causative agent, Feline Corona Virus (FCoV), is very similar to the human respiratory virus responsible for SARS and to coronaviruses from other animals.
FCoV is an infallible indicator of the felid basic type, from house cats to lions, with cheetahs being especially susceptible. Currently, host specificity of viruses is not considered diagnostic of a basic type. Nevertheless, these are additional pieces of evidence supporting the unique character of the feline basic type because, essentially, cats alone are susceptible, with rare exceptions.
The carnivores are grouped into two suborders:
--the catlike carnivores, or Feliformia, including the Felidae (cats), the Hyaenidae (hyenas), the Viveridae (civets), and the Herpestidae (mongooses);
--and the dog-like carnivores, or Caniformia, including the Canidae (dogs), the Ursidae (bears), the Procyonidae (raccoons), and the Mustelidae (weasels), as well as two marine families, the Otariidae (sea lions) and the Phocidae (seals).
Intro
The 38 species of extant cat have a very characteristic phenotype readily distinguished from other species of animals. Recently, the clouded leopard (Neofelis nebulosa) was separated into two species, which, if acknowledged, brings the total number of species to 39.The earliest cat-like carnivore family, the Nimravidae (paleosabers), includes two lineages that suddenly appear in the late Eocene jungles of North America.
--One lineage, represented by Hoplophoneus, was saber-toothed; the other lineage, represented by Dinictis, was rather like a modern serval. So convincingly cat-like are these fossils that originally they were called paleofelids and designated the first cats.
--The more recent cat family, the Felidae, include the modern cats, Felinae; and the neosabers, Machairodontinae, e.g. Smilodon.
The Nimravidae-Felidae ‘two-family’ hypothesis is supported less by ossifications and more by phylogenetic considerations; specifically, that the Felidae arose from Proailurus during the Miocene in the Old World. Proailurus, the animal currently nominated the first ‘true’ cat, was short, only 15 cm in length.
The next most recent cat, Pseudaelurus, had a clearly cat-like skull, based on its general morphology and dentition. It roamed Europe and North American during the Miocene. Several different forms of Pseudaelurus existed and these are believed to have formed the basis for the later radiation and diversification of the neofelid cats and the sabre-tooth tigers. Proailurus, from the Miocene, is the reason why New World paleosabers from the Eocene cannot be cats. As a result the origins of the paleosabers have had to be placed elsewhere; e.g. within the dog-like carnivores or even outside the carnivores. It is easy to see how the two-family hypothesis could be specious, based on preconceived notions.
Kitty Cats Can't Roar
Differences in ossification of skeletal features are not necessarily diagnostic of family status. A case 
--In small cats (the felines) the third bones (epihyoids) are ossified and short, and they cannot roar.
--In the larger big cats (the pantherines) the third epihyoids are cartilaginous and extended, and all but one of these cats can roar. In snow leopards the epihyoids are cartilaginous; however, they still cannot roar because they lack additional pads in their vocal folds.
Saber Tooth Extinction
Today both the paleosabers (Nimravidae) and neosabers (Machairodontinae) are completely extinct. 
Cat Color
Weigel believed that all of the extant melanistic coat colors and patterns arose from a single original type of relatively large dark spot. Werdelin and Olsson replaced Weigel’s proposal with evidence 
In other words, mechanisms of change such as recombination and natural selection appear sufficient to explain the variation in melanistic spot patterns observed within the cat family. Other patterns like the stripes of the tiger were not investigated in the study, but the same kind of mathematical modeling has been used to simulate formation of stripes in other animals.
Whole coat melanism in the domestic cat, jaguar and jaguarundi has been elucidated at the molecular level. These pelage pattern studies seem to reinforce the general observation that cats form a unique and well-defined group of animals.
Kitty Cat Lineage
Felis catus, the domestic cat, is believed to have arisen from the African wildcat, F. lybica, and not from the European wildcat, F. silvetris.F. lybica is easier to tame; it is far less shy of man.
Because domestic cats have a smaller adrenal gland, less epinephrine is produced and the animals are much quieter than wild cats.
These studies parallel observations by Trut et al. in studies of fox domestication. Together the studies suggest that the domesticated phenotype lies dormant within the genetic potential of many wild species.
A recent extensive study of mitochondrial DNA sequences from hundreds of domestic and wild cats across Europe, Asia, and Africa (including the domestic cat (F. catus), the European wildcat (F. silvestris), the African wildcat (F. libyca) and the Chinese desert cat (F. bieti), using the desert (sand) cat (F. margarita) as an outgroup, has clarified with great certainty the various ancestral relationships.
In addition, the domestic cat, the European wildcat, the African wildcat, and also the Chinese desert cat all appear to belong to a single species. Cementing this idea is the fact that mitochondrial DNA from domestic cats is routinely found in all three wild cat populations. Natural hybridizations between them are frequent events.
Hybrids/7 Steps
Hybrids between cats are often given unique names. Many of these names are contracted fusions of their common names; the first part indicating the male parent and the second part, the female parent. 
P. concolor × L. pardalis (puma × ocelot) bridges the gap between larger and smaller cats. --Hybridization data connects the largest cats, P. tigris and the massive Liger (400+kg), to the smallest cat, F. nigripes, via seven documented hybrid steps:
P. tigris (110–320 kg) × P. leo (120–250 kg) × P. pardus (30–85 kg) × P. concolor (35–100 kg) × L. pardalis (11–16 kg) × L. wiedii (3–9 kg) × F. catus (3–7 kg) × F. nigripes (1.5–2.5 kg).
Intralineage hybrids of the lynx always involve the bobcat (L. rufus) and are referred to as Blynx or Lynx cats. Five cat hybrids are bred commercially as pets: F. chaus × F. silvestris (Euro-chaus), L. rufus × F. chaus (Jungle lynx), L. rufus × F. catus (desert lynx), F. catus × P. bengalensis (Bengal cat), and Bengal cat × F. chaus (Jungle bob).
Feline-Specific Viruses
Feline Immunodeficiency Virus (FIV), the feline equivalent of HIV, has been shown to infect 30 of 
The deadly viral disease, Feline Infectious Peritonitis (FIP), is specific to cats. Its causative agent, Feline Corona Virus (FCoV), is very similar to the human respiratory virus responsible for SARS and to coronaviruses from other animals.
FCoV is an infallible indicator of the felid basic type, from house cats to lions, with cheetahs being especially susceptible. Currently, host specificity of viruses is not considered diagnostic of a basic type. Nevertheless, these are additional pieces of evidence supporting the unique character of the feline basic type because, essentially, cats alone are susceptible, with rare exceptions.
SUMMARY
Ability to hybridize is the most important criteria for including species within a common basic type. This criterion cannot be used directly on fossil forms.
Therefore, reports of
--extant cat hybrids,
--fossil skeletal evidence, and various other features, including
--molecular sequencing data,
--pelage patterns, and
--unique virus sensitivities,
all seem to suggest that the family Felidae represents a single clearly delineated basic type.
It is reasonable to assume that all felids arose from a single founder species and that they have passed through one or more adaptive radiations, exploiting their inherent morphogenetic potential to produce all of the known extant and extinct species of cat."
Barnabas Pendragon & Niko Winkler/CMI
Of the birds according to their kinds, and of the animals according to their kinds, of every creeping thing of the ground, according to its kind, two of every sort shall come in to you to keep them alive.
Genesis 6:20
It is reasonable to assume that all felids arose from a single founder species and that they have passed through one or more adaptive radiations, exploiting their inherent morphogenetic potential to produce all of the known extant and extinct species of cat."
Barnabas Pendragon & Niko Winkler/CMI
Of the birds according to their kinds, and of the animals according to their kinds, of every creeping thing of the ground, according to its kind, two of every sort shall come in to you to keep them alive.
Genesis 6:20