Competing ideas: A perfect fit for the evidence

We’ve seen that evaluating an idea in science is not always a matter of one key experiment and a definitive result. Scientists often consider multiple ideas at once and test those ideas in many different ways. This process generates multiple lines of evidence relevant to each idea. For example, two competing ideas about coral atoll formation (island subsidence vs. formation on debris-topped underwater mountains) were evaluated based on multiple lines of evidence, including observations of reef and atoll shapes, island geology, studies of the distribution of planktonic debris, and reef drilling. Furthermore, different lines of evidence are assembled cumulatively over time as different scientists work on the problem and as new technologies are developed. Because of this, the evaluation of scientific ideas is provisional. Science is always willing to resurrect or reconsider an idea if warranted by new evidence.