Even young children can identify a cat as a cat, whether it is a tiny black-footed cat (Felis nigripes) or a tremendous tiger, so similar in form are these carnivores. However, the diversity of species in the family Felidae and the relationships among them are a source of continuing wonder and study for specialists. Officially, the number of cat species is now 40, up from 36 a decade ago and 37 two decades ago. This number has fluctuated because of taxonomic reclassifications. Within limits, morphological analysis has helped biologists advance our understanding of the evolutionary relationships of cats. However, biochemical methods are now providing further resolution, which has determined eight lineages, or clades, among the 40 cat species and has enabled relationships among the modern cats’ ancestors to be traced back more than 10 million years. Modern field studies of most of the large and medium-sized species have been undertaken; however, facts about the small species remain virtually unknown. In this book, we have tried to bring together all that we do know.
Cat species constitute about 16 percent of the carnivores and fewer than 1 percent of all mammals. But the public’s interest in and admiration for cats well exceed their proportional representation among the mammals. There are hundreds of millions of domestic cats but fewer than 100 Iriomote cats (Prionailurus iriomotensis) and 50 Iberian lynx (Lynx pardinus). Lions, tigers, pumas, and leopards, the very large and medium-sized cats, can be seen in most zoos, although most of the smaller wild cats are not found there. Some species are represented by only a few specimens in the world’s museums.
Cats, which are highly specialized meat-eaters, range in size from 1 to 300 kilograms and appear at first glance to be variations on a common theme. On closer look, they are exquisitely intricate in their adaptation to place and circumstance. Most species are solitary, such as tigers and servals, although lions and cheetahs live in groups; all, however, have complex social lives. Cats live naturally on all continents but Antarctica and Australia; no cats have evolved there or on certain islands. However, by now people have taken domestic cats nearly everywhere. No cat species live on the ice or tundra or in the water, but they live nearly everywhere else. A strain of domestic cat has even adapted to living in freezers on freezer-living rats. One or more wild cat species live in habitats from true desert to mangroves and in nearly every terrestrial habitat in between.
Some cat species hunt in trees; some on the ground; and some on riverbanks, totally immersing themselves to catch fish. Wild cats hunt other animals as prey, the size of the cat species determining whether those prey are tiny insects or wild cattle weighing 1,000 kilograms. What they all have in common is the need for adequate prey and cover, which is also determined by the size of the species as well as its special adaptations. Cats’ position at the top of the food chain is easily disrupted. Populations of most wild cat species are now threatened with extinction. Seeing their beauty and discovering their diversity and life processes are essential steps toward saving these cats.