The first forests evolved during Earth's prehistoric past. Since then, all forests have developed in essentially the same way, by means of a process called succession.

The First Forests

The first forests evolved from ferns and other prehistoric plants, which, over time having adapted to the surrounding environment, grew more tree-like. Trees that preferred a warm, humid, tropical climate developed first followed by those that adapted to drier, cooler weather.

About 1,000,000 years ago, during the great Ice Ages, glaciers (huge, slow-moving rivers of ice) covered much of the planet and destroyed many of the world's forests. By the time the glaciers finally retreated, about 10,000 years ago, they had scoured the land of plants and soil, leaving only bare rock. Birch trees were among the first to return to the regions once covered by ice. In fact, the years between 8000 and 3000 B.C...