Roaring, Screaming and Purring

THE NATURAL HISTORY OF THE WILD CATS
 

by Andrew Kitchener
Comstock Publishing Associates/Cornell University Press, 1991 ($27.50)

There is a purity about cats, "the most exclusive of meat-eaters," with no options left save to hunt and scavenge for meat. After 35 million years of predation, cats are ruthless, efficient--and beautiful. We count 37 or so living species, 10 species of big cats who can roar like a lion, the rest smaller ones who can only scream and purr. (They are parted anatomically by the flexibility of the bone at the root of the tongue.)

Dr. Kitchener, an Edinburgh zoologist, has made a readable, up-to-date synthesis of what we know about cats, his account always strengthened by the comparative point of view. There are eight vivid chapters packed with graphs, maps and feline parameters. He includes a cat Who's Who in fine color photographs; it shows us most of the small cat species, plus three big cats that, unlike lions and tigers and leopards, are not in the public eye.

First catch your prey? No, first you must detect it. Cats depend on sight and sound. Their sense of smell is not as developed as in other carnivores; the number of their olfactory receptors is only half that of dogs. Cat hearing is acute, with a frequency response that ranges up toward 100 kilohertz, the better to pick up faint, short-range ultrasonic squeaks of rodents. Cats' keen eyes are proverbial. They have a dense retinal streak of cones optimized to pick up horizontal movement where we have a round spot of acute vision. Binocular vision is excellent, though color is less used. Cat vision has a wide dynamic range, good by night and by day. Domestic cats manage well in bright daylight, but they also respond to faint light down to one sixth the flux detectable by human eyes. Interlacing muscle fibers cross over the centerline of the cat's eye, to allow closing of the pupil to a very narrow slit instead of a small round opening like ours. Cat whiskers adjust position depending on the animal's activity; just at the moment of capture they are deployed like a net before the mouth. In the domestic cat, tactile and visual senses map into the brain in similar ways, perhaps making complementary images.

The hunt over, the bottom line is digestion. Among carnivores, cats have a short gut for their size. In East Africa, it is observed that vultures sometimes feed on lion feces but never on hyena or wild dog droppings. Analysis concurs; lion, leopard and domestic cat all show a digestive energy efficiency more than 10 percent below the domestic dog. Perhaps we know why. In cats, everything is designed for the climax of the kill, rather similar in all species. Cat design aims toward swift acceleration, no wasted weight for sudden high performance in swift sinuous motion. It is better to digest meat a little wastefully than always to be burdened at that climactic instant by the weight and bulk of a chemical plant not in constant use.

Cats are thought of as solitary, meeting only to fight or mate. In fact, they have a strong system of land tenure, in which males attempt to maintain exclusive hunting and breeding rights in some area. They pursue elaborate pattems of communication, using gestures, sounds and bodily contact--just look and listen. The necessary role of land registry and good fences that functions even when the principals are absent is taken by powerful olfactory signals, deliberately marked on soil and vegetation and dated by natural fading. Cats frugally use their urine and feces in the role of signposts and ink, carefully identifying owner and property by matching symbols.

There are two truly gregarious species: lions and the domestic cat. The field studies are many and subtle. In Her Majesty's Dockyard at Portsmouth, there is a feral population of "domestic" cats that may have been isolated within the dockyard walls for 200 years. They take almost no prey, for the rodents have long been controlled by poison, but they dine well on generous handouts and on garbage. The females there live in prides of a few animals, each on mapped ranges, whereas the males hunt and mate more at large, over an area 10 times that of the female ranges. Something like the polity of the Serengeti lions can be recognized among those naval cats.

One inexpert look at most of the small cat species is enough to suggest the origin of the domestic cat. Any one could be some neighbor's pet. The widely distributed Old World wildcat Felis sylvestris is the source of all the genes in today's domestic cats, a domestication some 8,000 years old, on the evidence of an old jawbone found on the wildcat-free island of Cyprus. Four thousand years later striped tabbies were raised and revered in Egyptian temples; ships then spread cats, like rats, worldwide.

The author politely does not mention the earliest phase of cat-human interaction, investigated by C. K. Brain near Pretoria. A million years ago or so our frail hominid ancestors in southern Africa were demonstrably commonplace prey for some big cats of the day, over a time very long by the scale of human history. Somehow the tables were turned. Cunning apefolk were no longer easy game: Was it language, fire or weapons? The cats cannot say.