Biological Systematics in the Evo-Devo era

Abstract

Abstract. evolutionary developmental biology (evo-devo) suggests a distinction between modular and systemic variation. in the case of modular change, the conservation of the overall structure helps recognizing affinities, while a single, fast evolving module is likely to produce a bonanza for the taxonomist, while systemic changes produce strongly deviating morphologies that cause problems in tracing homologies. Similarly, changes affecting the whole life cycle are more challenging than those limited to one stage. Developmental modularity is a precondition for heterochrony. Analyzing a matrix of morphological data for paedomorphic taxa requires special care. it is, however, possible to extract phylogenetic signal from heterochronic patterns. The taxonomist should pay attention to the intricacies of the genotype→phenotype map. When using genetic data to infer phylogeny, a comparison of gene sequences is just a first step. To bridge the gap between genes and morphology we should consider the spatial and temporal patterns of gene expression, and their regulation. Minor genetic change can have major phenotypic effects, sometimes suggesting saltational evolution. evo-devo is also relevant in respect to speciation: changes in developmental schedules are often implicated in the divergence between sympatric morphs, and a developmental modulation of 'temporal phenotypes' appears to be responsible for many cases of speciation.

Timeless standards for species delimitation

“…New technology-based means of gathering information have added to taxonomic quality control and sophisticated methods of data analysis. In taxonomy, new sources of data-e.g., nano CT-scan (Arillo et al 2015), evo-devo (Minelli 2015), 3D morphology (Khoury et al 2015), transcriptome phylogeny (Peters et al 2014), and cryopreservation centers-add to other sources of information and protocols that keep the biological system sound, including its nomenclature. But here again the new methods do not replace, but complement the traditional, tested methods and procedures (Schlick-Steiner et al 2010).…”

Multiplicity of Research Programs in the Biological Systematics: A Case for Scientific Pluralism

“…Generally speaking, this research program is just beginning to take shape and is poorly noticeable against the currently dominating cladistics based on the analysis of molecular genetic data [199]. Its specificity is in that it focuses on the evolutionarily interpreted variety of ontogenetic patterns of multi-cellular organisms [206,207]. The basis for this is provided by a synthesis of the considered phylogenetics in its rather widened sense, epigenetic typology (see Section 3.4 on it), and the evo-devo concept (a well-known abbreviation for the evolutionary developmental biology).…”

“…This tree is transformed into a corresponding evo-devo classification in the same manner as the phylogenetic one with its ranking scale being derived from a sequence of appearances of respective ontogenetic patterns in the evolution of multicellular organisms. The main characteristics of an evo-devo taxon becomes its specific ontogenetic pattern as a whole dynamic system, not reducible to any particular developmental stages [103][104][105]207]. All this provides biological systematics with a rich ontological basis and allows it to get rid of the overload reductionism brought in it by the above "genocladistics".…”

Multiplicity of Research Programs in the Biological Systematics: a Case for Scientific Pluralism

“…Generally speaking, this research program is just beginning to take shape and is poorly noticeable against the nowadays dominating cladistics based on the analysis of molecular genetic data [38]. Its specificity is in that it focuses on the evolutionarily interpreted variety of ontogenetic patterns of multicellular organisms [206][207]. The basis for this is provided by a synthesis of the just considered phylogenetics in its rather widened sense, epigenetic typology (see section 3.4 on it), and the evo-devo concept, which is an abbreviation for the evolutionary developmental biology considering patterns and mechanisms of the evolution of ontogeneses [208][209][210][211][212][213].…”

“…This tree is transformed into corresponding evo-devo classification in the same manner as the phylogenetic one, with its ranking scale being derived from a sequence of appearance of respective ontogenetic patterns in the evolution of multicellular organisms. The main characteristics of an evo-devo taxon becomes its specific ontogenetic pattern as a whole dynamic system not reducible to any particular developmental stages [103][104][105]207]. This allows systematics not only to deprive a pure molecular basis of the classification of its priority status but also to overcome a kind of traditional "adultocentrism" in the consideration of organismal anatomy [212].…”