Model organisms in evo-devo: promises and pitfalls of the comparative approach

Abstract

Evolutionary developmental biology (evo-devo) is a rapidly growing discipline whose ambition is to address questions that are of relevance to both evolutionary biology and developmental biology. This field has been increasingly progressing as a new and independent comparative science. However, we argue that evo-devo's comparative approach is challenged by several metaphysical, methodological and socio-disciplinary issues related to the foundation of heuristic functions of model organisms and the possible criteria to be adopted for their selection. In addition, new tools have to be developed to deal with newly chosen model organisms. Therefore, we present a modelling framework suitable to integrate data on individual variation into evo-devo studies on new model organisms and thus to compensate for current idealization practices deliberately suppressing variation.

Laboratory biases hinder Eco‐Evo‐Devo integration: Hints from the microbial world

“…Second, these studies have deliberately excluded realistic environmental variation, instead rearing organisms in controlled, constant conditions that may be both very different from and much more stable than those in natural environments (Gilbert, ). Although these approaches have generated a wealth of valuable results, they have also limited biological understanding to the extent that (a) model organisms do not capture key aspects of biological diversity, and (b) laboratory conditions intentionally restrict potential effects of natural environments (Bolker, ; Gasch, Payseur, & Pool, ; Gilbert, ; Minelli & Baedke, ). Thus, some important questions about the developmental and evolutionary processes occurring within specific ecological contexts have remained unsolved, or even unaddressed.…”

Quantifying the living fossil concept

“…Equating little change at the molecular scale as evidence for the living fossil status for coelacanths, however, has led to many rebuttals (Bockmann et al, 2013;Chalopin et al, 2014;Forconi et al, 2014;Naville et al, 2015). In particular, its publication and the publication of similar articles have reignited arguments over the need to avoid 'progressivist' language in evolutionary discourse Grandcolas et al, 2014;Minelli and Baedke, 2014). As discussed above, under a progressivist or gradist interpretation of evolution the term living fossil may be interpreted to mean a 'low-ranked' or 'basal' taxon that is more closely related to an extinct ancestor than FIGURE 4.…”

“…Some authors place increased focus on living fossils constituting "evolutionary relicts" , others focus on "little change through time" , and others still interpret the term to mean Lazarus taxa (Smith, 1939). More recently, there have been efforts to reject the living fossil term entirely as it is thought to recall Haeckel's scala naturae and is a product of bad 'tree-thinking' Grandcolas et al, 2014;Minelli and Baedke, 2014). It is argued that the term living fossil is a form of 'progressivist' language that can promote a false interpretation of evolution where life is organised into 'higher' and 'lower' ranks (Rigato and Minelli, 2013).…”

Grand challenges in evolutionary developmental biology

“…There has been much debate about the best criteria for adding new items to the select list of model species, but none of them seems to pass rigorous logical scrutiny (discussed in Jenner, 2006;Minelli and Baedke, 2014). Empirically, "random walks" to explore closer or increasingly distant relatives of the most fashionable model species have regularly revealed the idiosyncrasies of the model, most unexpectedly among morphologically conservative animals such as nematodes.…”