Evolution and the Levels of Lineage

University Of Utah, Salt Lake City UT

Investigators

Abstract

General Audience Summary This philosophy of biology project engages in conceptual analysis of the notion of a lineage, which is roughly a line of decent from ancestors, and related notions. The project focuses on questions of what lineages are, how they are nested, and how this hierarchical organization was built through evolution. The scope of the project is broad and the consequences far-reaching. How lineages interact across levels is centrally important, for example, in studying how gut microbes influence mate preference in fruit flies and impact what we treat as units of selection; in how we conceive of when polar and brown bears diverged, given the hybridization between those groups; or in how we think about parental lineages as we manipulate how mitochondrial lineages are transmitted from one human generation to the next. A particularly impressive feature of the project is its interdisciplinary focus. The project includes an interdisciplinary workshop, Species in the Age of Discordance, scheduled for spring 2017. The workshop will directly engage the public through outreach events including a Biohumanities Public Lecture Series event on taxonomy in the 21st century, which will be held at the downtown Salt Lake City Public Library. The PI will also coordinate with the Utah Museum of Fine Arts and the Natural History Museum of Utah on an exhibit featuring the work of artists collaborating with taxonomists, including a public lecture. Technical Summary The central aims of this proposal are to articulate a "levels of lineage" perspective, describe the core commitments of that perspective, and identify how these inform researchers and generate novel research questions. Biological lineages are hierarchically organized, but nesting of those lineages may be "leaky" due to a variety of evolved biological mechanisms and processes. Detecting these patterns of discordance provide evidence for a sophisticated multilevel account of evolution, and require biologists to revise core commitments (theoretical, conceptual, methodological, etc.). The levels of lineage perspective identifies the conceptual resources biologists draw on in these projects. It will extend and consolidate recent work in microbiology, systematics, phylogenetics, and evolutionary and population genetics, among other fields. This project aligns with recent work in demanding a diachronic approach by treating the core apparatus of biology as products of evolution. For example, rather than treating the biological hierarchy as a background assumption, researchers are instead prompted to ask, why this hierarchy, or even one at all? Answering these questions provides further resources and research questions.