When and how was Ecology born, and how did we come to understand it?

Background/Question/Methods

Over 200 years ago, world explorers were developing the understanding that similar, if not identical, vegetation grew in widely separated parts of the earth. Further, that these species favored certain environmental conditions. Extreme environments, such as wetlands, alpine, arid and tropical regions provided the most interesting examples. The soils, rainfall, elevation, and temperature regimes of these places clearly had much in common, and ideas of a “characteristic” flora (and fauna) developed early. It was also recognized that common weeds colonized disturbed fields and bare soil, and tended to be restricted to such sites rather than generally distributed. The naturally occurring groupings were commonly referred to as “plant associations” by the end of the 19^th century, and, often, their components as “communities.” What did this imply? Was there an appreciation of interactions among the plants (and animals) living in this community? Generally, there was not. Most descriptions and discussions of the time focused on the appearance of the species, and could be considered examinations of anatomy and taxonomic characteristics. In many ways, these results led scientists to appreciate how they were adapted to specific habitats.

Results/Conclusions

In 1895 Warming published the first textbook of “ecology,” based on his deep appreciation of plant geography. It described the major vegetation divisions of the world, attempting to explain how similar challenges, such as aridity, flooded or saline soils, frigid temperatures, etc. had been “solved” through similar responses, though the species may have originated from different genera or families. Thus there were plants of similar appearance in corresponding habitats world-wide. About this time, Clements developed the concept that vegetation cover is not a permanent condition but may slowly change. He proposed that the development of vegetation can be related to stages resembling the development of an individual organism, restoring itself towards the mature "climax,” vegetation best suited to local conditions. This still wasn’t the “community.” By the 1930s, community was defined as “a group of actually or potentially interacting species living in the same place.” In still another source: “a group of plants and animals living and interacting with one another similar environmental conditions.” Thus the concept that the species in a community interact with one another has been developed. Here, finally, ecology as we know it has been elevated to a working concept, though changing often over time.