The origin of evolutionary storytelling

Abstract

Phylogenetics emerged in the second half of the nineteenth century as a discipline dedicated to constructing descriptive and explanatory narratives that traced the evolutionary origins of taxa and traits. Because ancestors and evolutionary transformations are empirically inaccessible, phylogeneticists had no choice but to use their more or less informed imagination to gain access to this epistemic hinterland. The explanatory power of phylogenetic hypotheses resides in their ability to trace back traits to their evolutionary origins. Hypothetical ancestors therefore became important epistemic tools as they were deliberately equipped with characters that could function as suitable evolutionary precursors for traits of interest. I argue that the precursor potential of hypothetical ancestors therefore became the first, more or less objective, phylogenetic optimality criterion.