What is “homology thinking” and what is it for?

Abstract

In this paper I examine the thesis by Marc Ereshefsky that, in evolutionary biology, there is a third style of thinking, besides the well-known "population thinking" and "tree thinking." Ereshefsky proposes "homology thinking" as a third approach, focused on the transformation of organismal phenotypes. In this short commentary, I aim at identifying the underlying biological assumptions for homology thinking and how they can be put to work in a research program within evolutionary biology. I propose that homology thinking is based on three insights: 1) multicellular organisms consist of developmentally individualized parts (sub-systems); 2) that developmental individuation entails evolutionary individuation, that is, variational quasi-independence; and 3) these individuated body parts are inherited, though indirectly, and form lineages that are recognized as homologies. These facts support a research program focused on the modification and origination of individuated body parts that supplements and puts into perspective the population genetic and phylogenetic approaches to the study of evolution.

Gene Regulatory Network Homoplasy Underlies Recurrent Sexually Dimorphic Fruit Fly Pigmentation

“…In addition to explaining how phenotypes develop, GRNs are the lens through which we can observe important aspects of a phenotype's evolution. Important here, GRNs provide a critical context in which we might be able to detect the presence (common GRNs) or absence (distinct GRNs) of homology relationships (Wagner, 2016). Moreover, the examination of GRNs that govern recurring traits could reveal whether and how similar traits converge at the molecular level.…”

Origin, Function, and Effects of Female Orgasm: All Three are Different

“…We believe that the position that Dr. Komisaruk and colleagues have defended in 2006 is akin to methodological adaptationism and inherits its shortcomings. Lloyd proposes an alternative approach she calls the “evolutionary factors approach.” In our original paper (Pavličev and Wagner, ), we use a similar approach called “homology thinking” (Ereshefsky, ; Ereshefsky, , Wagner, ). We turn to this perspective in the next session.…”

“…Lloyd proposes an alternative approach she calls the "evolutionary factors approach." In our original paper (Pavličev and Wagner, 2016), we use a similar approach called "homology thinking" (Ereshefsky, 2007;Ereshefsky, 2012, Wagner, 2016. We turn to this perspective in the next session.…”

Mammalian organogenesis in deep time: tools for teaching and outreach

“…(access: 2016-11-25). This is basically an exercise in identifying structures that are homologous, and as such emphasizes homology thinking, a central aspect in evolutionary biology that benefits from the tree-thinking perspective (Ereshefsky 2012;Wagner 2016), also central here. 3.…”