Thread by @yoginho

James DiFrisco reports on our collaboration on mechanistic explanation and process in evo-devo. #ISHPSSB19

DiFrisco: static gene regulatory networks dominate as explanation for the structure of the genotype-phenotype map. But static network graphs do not constitute causal-mechanistic explanations. #ISHPSSB19

DiFrisco: prominent examples of network-based explanations are provided by the work of Eric Davidson and colleagues, or Günter Wagner’s genetic theory of homology, based on character identity networks (ChINs). #ISHPSSB19

DiFrisco mentions three basic problems with gene regulatory networks as causal-mechanistic explanation of the genotype-phenotype map: (1) the problem of genetic determinism, (2) of correspondence, (3) and of diachronicity. #ISHPSSB19

DiFrisco: problem of determinism – regulation at all levels of organisation, non-genetic inheritance, transmission depends on cell static/organismic activity, genetic program hard to map onto organismic substrate & not exclusive explanation for faithful reproduction. #ISHPSSB19

DiFrisco: the problem of correspondence – evolution at network and phenotypic level dissociable; developmental system drift means homologous traits do not need to be based on conserved networks. #ISHPSSB19

DiFrisco: the problem of diachronicity – static network graphs cannot causally explain developmental processes since they lack extension in time. #ISHPSSB19

DiFrisco: how do we go beyond networks? Dynamic mechanistic explanation involving mathematical modelling to reconstitute the complex and non-linear causal flow in regulatory systems. #ISHPSSB19

Silvia Basanta Martínez follows my own presentation, talking about late developmental processes and their role in generating selectable phenotypic variation and evolvability. #ISHPSSB19

Silvia emphasises the role of reproduction in evo-devo and our understanding of evolvability. #ISHPSSB19

Basanta Martínez: reproductive evolution in eutherians – originally invasive ancestral implantation, evolution of decidual cells, and early lineage specification. #ISHPSSB19

Basanta Martínez: inter-individual relations during reproduction affect evolvability and variational properties, active role of the mother, which is not just a passive environment. #ISHPSSB19