Ecological Succession

There is a series of ponds at the south end of Lake Michigan arranged in the order of their age; age is determined by the physiographic history; by the relative amount of humus and bare bottom, and by the quality and quantity of vegetation. 2. Species of fish are arranged in these ponds in an orderly fashion; the order is related to the age of the ponds. 3. The ponds of different ages represent stages in the history of older ponds. 4. The horizontal series of fish communities is ecologically representative of the succession of fish communities within the older ponds. 5. The method employed here is similar to physiographic analysis; the motives and possible results are similar but more strictly biological, because the causes of the succession are the organisms themselves.