Before men learned to cultivate plants and to domesticate animals, subsistence was always an uncertain matter. They roamed about in one vicinity until nature could no longer supply their needs, then left the exhausted land to recover itself while new territory afforded means for satisfying hunger. After fire became such a potent factor, as we have seen, a fixed abode was desirable. It fell to the lot of women to stay and tend the hearth. Shut off from the long expeditions undertaken by men, they soon learned to make as much as possible of the space around about their homes. Sticks were sometimes placed around plants or bushes to protect them from the careless step until their fruits matured. Occasionally plants were dug up and replanted nearer the hut. The garden and grain field were but natural results of this spirit of husbanding the stores provided by mother earth. While women were the first to domesticate plants in the simple way just indicated, not much came of it until men adopted the idea and carried it further. With sharp sticks they scratched the soil and with the help of animals they trod in the seeds. Irrigation was sometimes needed--as in Egypt--to insure good crops. Thus from slight beginnings developed the agriculture of the world. With reasonable labor and painstaking, the tiller of the soil could be sure of a living for himself and his family, and before historic records illumine the life of several nations, farming was well understood. Indeed it is safe to say that until very recent times methods followed by tillers of the soil in quite a number of countries advanced very little upon those of the prehistoric man. It is interesting to trace the history of present day foods, grains, vegetables and fruits, with the attempt to ascertain where each was native. All have been greatly improved by cultivation and not alone our varieties, but even distinct fruits and plants have resulted from man's propagation. Often the original species have been vastly improved. For example, the potato was a native of Chili. Found there in the sixteenth century of our era, it was described as "watery, insipid, but with no bad taste when cooked." It is supposed that it was taken from some Spanish ship to Virginia, and in the latter part of the same century carried to Europe. Its cultivation has spread over many countries, and from a small, watery tuber it has been brought to large size, mealiness and taste agreeable to the palate. Even today it flourishes in its wild state in Chili and Peru. The cabbage was once a weed, growing on rocks by the seashore. By man's care it has been developed to the vegetable widely used today; moreover, its blossom has been exaggerated until a wholly new vegetable in the form of the cauliflower is the result.