Forest Preserve District of Cook County, Illinois
Nature Bulletins
Newton Home Page

Introduction and Instructions

Search Engine

Table of Contents



Domestic Animals that go Wild
Nature Bulletin No. 743   February 15, 1964
Forest Preserve District of Cook County 
Seymour Simon, President
David H. Thompson, Senior Naturalist

The domestication of animals began far back in prehistoric times. We can imagine that it started when primitive man or his children captured wolf cubs and made pets of them which became the ancestors of our dogs. Other kinds which he found useful or which appealed to his fancy have been fed, sheltered and protected with almost as much care as the human members of his household.

Living generation after generation under man's control, these tended to change their habits and become tamer than their wild relatives. By the artificial selection of breeding stock, these domesticated animals have been greatly modified to fill man's needs for better food, clothing and work animals. Others have been bred merely to satisfy his whims for unusual colors, sizes and shapes.

This is the question. Have these animals become so dependent on man over the ages that they are unable to survive and multiply in the wild?

Almost all of the livestock and poultry in this country are descended from breeding stock imported from the Old World where our most important kinds were domesticated by prehistoric man. These include cattle, sheep, goats, hogs, horses, asses, dogs, cats and chickens. Within historic times rabbits, ducks, geese, guinea hens, peacocks and pigeons have been added. The turkey is the only domestic animal native to this continent.

On his second voyage to the New World in 1493 Columbus brought sheep, goats, cattle, horses and hogs. It is supposed that from his eight porkers sprang all of the swine that populated the West Indies and ran wild through the jungles and canebrakes. The Spanish invaders scattered them widely as meat on the hoof for their expeditions. These and other hog immigrants have made themselves at home in the swamps, lowlands and forests of the Gulf Coast and lower Mississippi Valley.

Barnyard swine became adapted to man's meal hours, feeding by day and sleeping at night. When they go wild they return to the schedule of their untamed ancestors, lying in a shady lair all day and foraging at night.

When De Soto crossed the Mississippi in 1541, his men either abandoned or lost some of their horses. It is believed that these formed the nucleus of the bands of wild horses, or mustangs, which are still found in some western states. In like manner, the present herds of wild burros may trace back to the pack animals used by the Spaniards while mining for gold and silver in the Southwest. Texas longhorn cattle which once roamed the western ranges were extremely hardy beasts descended from a 15th century breed brought from Spain.

The so-called San Juan rabbit is a "Belgian hare" which has reverted to type and threatens to become a serious pest. A lighthouse keeper in Puget Sound released a few on his island as a source of fresh meat. Eventually they stripped it of vegetation, spread to other islands of the San Juan group, and multiplied enormously. When sportsmen began to ship these animals into the Midwest for training their hunting dogs, farmers became alarmed because this is the same European rabbit that ruined grazing lands in Australia and New Zealand.

When carp were introduced into the United States in the 1870s about two-thirds of them were of the cultivated "mirror" and "leather" varieties which have few or no scales. Since that time, these strains have been almost completely crowded out by wild-type fish. The ornamental goldfish which has overrun many of our streams and lakes, loses its bizarre shapes and colors within a few generations.

The honeybee, having been associated with man for over 4000 years, is frequently regarded as a domestic animal. The bee submits to life in a hive but, left to itself, readily deserts it for a hollow tree.

To return to the Nature Bulletins Click Here!
Hosted by NEWTON

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (, or at Argonne's Educational Programs

Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Sponsered by Argonne National Labs