Anticipating Scientific Revolutions in Evolutionary Genetics

Abstract

In day-to-day research in evolutionary genetics, it often seems as though our knowledge is bounded. We steadily perceive at least two major limitations on our capacity to understand the mechanisms and history of evolution. First, knowledge seems limited by the nature of history. It is certainly not useful to pursue a historical record that does not exist, as may be the case for many kinds of histories. Not all events, evolutionary or otherwise, leave an imprint in DNA or other media; and of the imprints that are made, none are expected to last indefinitely. Second, for the special case of evolutionary genetic histories, knowledge seems limited by the irreducible nature of DNA sequences. It does an investigator little good to try and glean more information from DNA than is available in the DNA sequence. So far as we know, every “A” base (adenine), for example, is like every other, and the information in a DNA sequence is in quanta (it is digital, base 4). These everyday perceptions of limits to inquiry may seem reasonable, and so they may provide a starting point for accessing what kinds of questions are more feasible than others. Perhaps we cannot reveal all of evolutionary history, but maybe we can understand and assess the limits to our knowledge of this history.