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A fundamental goal of science is to discover rules. If we find that two chemicals react to yield a specific compound, then we expect that to reflect a general truth that other scientists can repeat. The situation is not so simple in biology, however, because our experimental results depend, to some degree, on the model system we are using.
Model systems have been around for as long as biology has been a science. We posit a general truth by finding organisms in which that truth is most evident. Darwin used pigeons to study the heritability of biological variation. Mendel used peas to show trait inheritance. Researchers assumed that principles observed in one organism would be true for all, and for a long time, this generally ...
