Paleoecology, the scientific study of ancient environments and the interrelationships of their plants and animals, and paleolimnology, the scientific study of evidence of ancient inland waterways, including lakes, ponds, freshwater marshes, and streams, were both established at the end of the nineteenth century. The roots of both disciplines can be traced to early nineteenth-century botanical and chemical studies, and later, geological studies of the consolidated sediments of ancient lake beds, in which their organisms and environments were examined in relationship to both the lakes and the surrounding uplands.

By the early 1920s, limnologists began to collect sediment cores from lakes and to interpret stratigraphic data from plant and animal fossils as a record of a lake's history. This provided clues to how lakes had changed over time as a result of either natural events or human activities. Data collected from lakes and wetlands provide baselines to...