1.4: Methods of ecology

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How do ecologists do ecology? Often, they start with observation, then move to theory—trying to ﬁt observations together to make sense as a whole. Theory then leads to expectations, which in turn lead to experiments. Commonly, experiments aren’t undertaken until there is some theory to be tested and understood.

Observation
Theory
Experiment
Serendipity

Observation, theory, and experiment, however, are not the whole story. A large part of science turns out to be serendipity—luck and chance—capitalizing on chance and doing something with it. One example is Alexander Fleming, who discovered penicillin. Some of the bacterial cultures in his lab became contaminated with penicillium mold and the cultures died. That ruined his experiment.

He could have written a memo to the laboratory staﬀ ordering “Always keep mold away from our bacterial cultures. It destroys the cultures and will ruin the hypotheses we are trying to test.” But instead he capitalized on the serendipity, wondered what was happening, and found a substance in penicillium mold that kills bacteria. Fungi and bacteria have been archenemies for perhaps a billion years. Fleming’s discovery has helped physicians actually cure disease, rather than being limited to diagnosing and prognosticating.

Following up on chance is, then, a large part of science. By the way, for an interesting paper, read the original 1929 report by Fleming about penicillium. It is so understated. He writes “the name ‘penicillin’ has been given to ﬁltrates of broth cultures of the mould.” No one had heard of the word before. Then he suggests that “it may be an eﬃcient antiseptic.” One of the greatest discoveries of all time and only, “it may be an eﬃcient antiseptic.”

Cedar Creek is a University of Minnesota research site about thirty miles north of the University’s Saint Paul campus, and is one of the classic ecological research sites in the world. Pictured in Figure \(\PageIndex{1}\) is an experiment set up by Prof. David Tilman. While very carefully designed, it came about because of serendipity—the chance event of a deep two-year drought that altered the abundances of species in a particular way and triggered the idea for this experiment.

Keep your eyes open for such chance events; they can crop up anywhere.

Cedar Creek.JPG — Figure \(\PageIndex{1}\) *Observations and experiments testing theory at Cedar Creek. This entire experiment was established following up on serendipity.*