Abstract

Abstract: A common explanatory error concerns conflating epistemological roles between two domains. Here I deal with a special case: when explanations of development replace evolutionary explanations or vice versa. Ernst Mayr famously distinguished between proximate and ultimate causal explanations in biology. His view was central to keeping development outside the theory of evolution. Nevertheless, the explanatory role of developmental processes in evolution is a central theme in current theoretical biology, which has led to several revisions of Mayr’s distinction. In the following, I will review these reviewers to determine whether the integration of development and evolution is based on an appropriate reinterpretation of Mayr’s distinction. The revisionists often propose an interactionist alternative in which proximate and ultimate causes interact to produce evolved traits. The most common interactionist account relies on the idea of reciprocal causation. I will argue that this perspective is still problematic and that the boundaries between explanatory domains are crossed. Instead, we should rethink Mayr’s distinction by adopting an alternative view of evolutionary causation, the so-called Statisticalist view on natural selection, which claims that the only level of causation is the proximate level. By excluding two different levels of causation, this framework is able to avoid fallacious explanations and fully consider reciprocal causation as a proximate phenomenon. I introduce the concept of “statistical reciprocity” to explain the statistical effects of (proximate) reciprocal causation in ultimate explanations and outline some ideas of “population ontogenetics” as a prominent framework for unifying development and evolution beyond interactionist positions.