Does Biology Have Laws? The Experimental Evidence

In this paper I argue that we can best make sense of the practice of experimental evolutionary biology if we see it as investigating contingent, rather than lawlike, regularities. This understanding is contrasted with the experimental practice of certain areas of physics. However, this presents a problem for those who accept the Logical Positivist conception of law and its essential role in scientific explanation. I address this problem by arguing that the contingent regularities of evolutionary biology have a limited range of nomic necessity and a limited range of explanatory power even though they lack the unlimited projectibility that has been seen by some as a hallmark of scientific laws.