Cellular self‐organization: An overdrive in Cambrian diversity?

Abstract

During the early Cambrian period metazoan life forms diverged at an accelerated rate to occupy multiple ecological niches on earth. A variety of explanations have been proposed to address this major evolutionary phenomenon termed the "Cambrian explosion." While most hypotheses address environmental, developmental, and ecological factors that facilitated evolutionary innovations, the biological basis for accelerated emergence of species diversity in the Cambrian period remains largely conjectural. Herein, we posit that morphogenesis by self-organization enables the uncoupling of genomic mutational landscape from phenotypic diversification. Evidence is provided for a two-tiered interpretation of genomic changes in metazoan animals wherein mutations not only impact upon function of individual cells, but also alter the self-organization outcome during developmental morphogenesis. We provide evidence that the morphological impacts of mutations on self-organization could remain repressed if associated with an unmet negative energetic cost. We posit that accelerated morphological diversification in transition to the Cambrian period has occurred by emergence of dormant (i.e., reserved) morphological novelties whose molecular underpinnings were seeded in the Precambrian period.

Redox-Mediated Rewiring of Signalling Pathways: The Role of a Cellular Clock in Brain Health and Disease

“…Due to such prolonged development, interactions with external stimuli more effectively reshape the postnatal wiring of the human brain as opposed to the predominance of intrinsic self-organisation of the brain in other primates [8]. Given that metazoan developmental landscape is shaped by decentralised self-organising interactions between individual cells [9][10][11][12][13], the acceleration or deceleration of developmental dynamics suggests the existence of a hypothetical "cellular clock" which determines the rate of cellular events.…”