Integrating Complex Environments to Reveal Integrated Phenotypes by Cryptic Developmental Plasticity

Phenotypic integration can be studied at different biological levels and is often interpreted from developmental and/or functional perspectives. Increasing literature recognizes the role of developmental plasticity revealing novel complex and integrated phenotypes, which likely express interactions between development and function because the animal performs ecological tasks while developing in a given environment. Here, we detail an approach designed to investigate the cryptic plastic potential for revealing novel phenotypes within specific developmental environments. This framework integrates the complexity of multifactorial environments with multidimensional plastic responses. We introduce the concepts of Parental Developmental Environment (PDE) and Experimental Developmental Environment (EDE). The PDE corresponds to the prevailing environment of a population, in which a particular phenotypic range is expressed, whereas the EDE represents a new set of environmental conditions that differs from the PDE and enables cryptic developmental processes to reveal novel phenotypes, thereby expanding the phenotypic space. We illustrate application of this approach in studies using Anostomidae, a fish family of neotropical distribution. Using this experimental framework, we can evaluate how cryptic plasticity reorganizes the development and structures variation into novel phenotypes. This devo-eco approach offers a complementary and experimentally grounded expansion of existing research programs.