Does the extended evolutionary synthesis entail extended explanatory power?

Abstract

Biologists and philosophers of science have recently called for an extension of evolutionary theory. This so-called 'extended evolutionary synthesis' (EES) seeks to integrate developmental processes, extra-genetic forms of inheritance, and niche construction into evolutionary theory in a central way. While there is often agreement in evolutionary biology over the existence of these phenomena, their explanatory relevance is questioned. Advocates of EES posit that their perspective offers better explanations than those provided by 'standard evolutionary theory' (SET). Still, why this would be the case is unclear. Usually, such claims assume that EES's superior explanatory status arises from the pluralist structure of EES, its different problem agenda, and a growing body of evidence for the evolutionary relevance of developmental phenomena (including developmental bias, inclusive inheritance, and niche construction). However, what is usually neglected in this debate is a discussion of what the explanatory standards of EES actually are, and how they differ from prevailing standards in SET. In other words, what is considered to be a good explanation in EES versus SET? To answer this question, we present a theoretical framework that evaluates the explanatory power of different evolutionary explanations of the same phenomena. This account is able to identify criteria for why and when evolutionary explanations of EES are better than those of SET. Such evaluations will enable evolutionary biology to find potential grounds for theoretical integration.

Educational potential of teaching evolution as an interdisciplinary science

“…Gene-focused conceptualizations of evolution may, currently, not sufficiently support this integration. As Baedke et al (2020) point out, standard conceptualizations of evolutionary theory stemming from the MS present idealizations, abstracting out developmental processes and proximate interactions. Such idealization may help in understanding broader phylogenetic changes across a range of phenomena, but they may provide rather limited understanding if the interest is in a more concrete account of the role of developmental processes and other proximate mechanisms in explaining particular phenomena.…”

Conceptual clarification of evolution as an interdisciplinary science

“…On the other hand, Baedke et al (2020) argue that disagreements regarding an extension of evolutionary theory should and can not be resolved by the amount of empirical evidence for either one, since many examples exist in which two different explanations, stemming from either a gene-focused or extended conceptualizations, seem to be equally supported by evidence, thus stifling progress in this debate. Rather, the debate should be based on the question of whether an explanation is more powerful in terms of helping to achieve a particular level of understanding of a phenomenon.…”

Challenges with conceptualizations of evolution in biology education

“…We argue that this tendency to focus on idealized evolutionary dynamics as applied to special cases, may prove difficult if such idealization is thought to represent "the truth" and to apply to all evolutionary explanations of observable traits. As Baedke et al (2020) point out, standard conceptualizations of evolutionary theory stemming from the MS present idealizations , abstracting out developmental processes and proximate interactions. Such idealizations then influence the choice of model organisms for which these idealizations hold, such as organisms with "invariant body plans, low levels of developmental plasticity, and ease of genetic manipulation" (Baedke, et al, 2020).…”

“…As Baedke et al (2020) point out, standard conceptualizations of evolutionary theory stemming from the MS present idealizations , abstracting out developmental processes and proximate interactions. Such idealizations then influence the choice of model organisms for which these idealizations hold, such as organisms with "invariant body plans, low levels of developmental plasticity, and ease of genetic manipulation" (Baedke, et al, 2020). Especially when it comes to understanding human evolution, the transfer of such idealized models becomes significantly problematic.…”