Tangled Banks, Braided Rivers and Complex Hierarchies: Beyond Microevolution and Macroevolution.

Ever since the Modern Synthesis, a debate about the relationship between microevolution and macroevolution has persisted - specifically, whether they are equivalent, distinct, or explain one another. How one answers this has become shorthand for a much broader set of theoretical debates in evolutionary biology. Here, we examine microevolution and macroevolution in the context of the vast proliferation of data, knowledge, and theory since the advent of the Modern Synthesis. We suggest that traditional views on microevolution and macroevolution are too binary and reductive. For example, patterns and processes are not confined to micro- and macro- domains; they are interconnected at various temporal and spatial scales and across hierarchical entities. Further, biological entities have variably fuzzy boundaries, and evolutionary processes that influence macroevolution occur at micro- and macro- levels. In addition, these conceptual advances in phylodynamics have yet to be fully integrated with contemporary macroevolutionary approaches. Finally, holding microevolution and macroevolution as distinct domains thwarts synthesis and collaboration on important research questions. We propose that the focal entities and processes considered by evolutionary studies be contextualized within the newfound complexity of the multidimensional, multi-modal, multi-level phylogenetic system.