Natural History of the cat

Author: Kyungmin Shin

 

Domestic cats Felis catus or domesticus are primarily descendents of the wild cat of Africa and southwestern Asia, Felis silvestris libyca. Cats appeared first in the Early Pliocene epoch, 5.3-3.4 million years ago, as a weasel-like creature called Miacides, the ancestor of all living carnivores. The earliest record of the domestication of cats began about 3,000BC in Egypt as a protection for their granaries and from rodents [1].

The average height of an adult domestic cat is about 20 to 25 centimeters at the shoulders. The length from the tip of the nose to the base of the tail averages 46 to 51 centimeters, and the tail is about 25 to 38 centimeters long, approximately ¾ the length of the body. Females usually weigh from 2.7 to 4.5 kilograms and males from 4.5 to 6.8 kilograms, depending on skeletal size. The head is large compared with the rest of the body with large ears but short nose and jaws. Domestic cats have five toes on each of their forepaws, but only four toes on each back paw. The claws are drawn back into their paws when not in use, but could be unsheathed in a split second [2].

The legs appear short compared to the body length, but powerful and flexible. The cat is a quadruped, possessing strong limbs and shoulder structures to climb trees, run, and jump from heights, but the movements are restricted in angle of their motions in shoulder joints. Therefore they cannot circumduct the shoulder as human can. However, a cat can stretch its forelegs wide apart to hug the body of an enemy and hold it close. The forepaws can be tucked under the chest when the animal crouches, can be curved around the head when the animal washes behind the ears and also could be turned palm up for washing under and between the toes. Cats are digitigrade; therefore, they walk on their toes [3].

Cats have very acute senses of smell and hearing. The ears of a cat can rotate rapidly to identify the source of a sound and are able to respond to frequencies up to 25,000 vibrations per second. Thus a cat is able to hear ultrasonic noises made by small rodents, an advantage when hunting [2]. However, even though their sights are good, the capability does not exceed that of human except in dark. In bright light, a cat's pupils contract to narrow vertical slits, but in the dark, they become round openings that admit maximum amount of light. The range of color a cat can see is smaller, and because the eyes are located on the front of the head, it cannot see directly under its nose, but it still has excellent depth perception. Cats do not have eyelashes, but have a nictitating membrane to keep eyes moist. They also have whiskers or vibrissae on the upper lip on each side of the nose, and smaller ones above the eyes, on cheeks, and on back of the forepaws as another sense organ for touch [4].

The teeth in cats are specialized. The upper canines point almost straight down and the lower ones are curved, and these 4 canines are used for stabbing and holding prey. The large incisors function as grooming aids. Cats have only few molars and premolars are used for cutting and since they do not have teeth for crushing, they eat their food by slicing it. Their tongues are rough and used for stripping flesh off the bones of prey as well as grooming tool to clean and comb fur with the incisors [4, 5].

Cats communicate through sounds such as growling or hissing. They may purr when content or angry. They also communicate through odors. Cats have scent glands on their foreheads around their mouth, and near the bases of their tails. They rub these glands against people or objects for marking. Only a few other animals besides cats can detect this odor [6, 7].

Domestic cats, still possessing the characteristics of the wild, are primarily nocturnal and carnivores, thus still hunting rodents and birds. The cat may have 2-4 litters per year, having 1-6 young per litter. Their breeding season is not limited, thus females are repeatedly in heat if prevented from mating initially, and they gestate for approximately 63 days. A cat's life span is about 12-15 years. They have varying densities of one to more than 2,000 per square kilometer. The home ranges of solitary cats are less than 50 acres for females and more than 100 acres for males. Although most domestic cats are solitary, there are some group-living cats, and they have smaller home ranges than solitary cats do. Males tend to be solitary while females sometimes live in small groups, but males and females do not form close bonds with each other [1,8].

 

References:

1. Encyclopedia Britannica, vol. 15. 1998.
2. Encyclopedia America, International Edition, vol. 5. 1998. Grolier Incorporated, Danbury, Connecticut.
3. Encyclopedia Britannica Intermediate, 1999. Encyclopedia Britannica, Inc.
4. The World Book Encyclopedia. 1986. World Books, Inc., Chicago.
5. Turner, Dennis C. and Bateson Patrik. 1988. The Domestic Cat: the Biology of Its Behavior. Cambridge University Press, Cambridge.
6. Leyhausen, Paul. 1979. Cat Behavior. Garland STPM Press, New York.
7. Nowak, R. 1999. Walker's Mammals of the World. Johns Hopkins University Press, Baltimore & London.
8. Beadle, Muriel. 1997. "The Cat, History, Biology and Behavior." New York, New York, Simon & Schuster.