Meeting Abstract
72.1 Monday, Jan. 6 08:00 Controlling Nature & Nurture: Why experiments with wild type are insufficient for understanding adaptation to environmental change HEDGECOCK, D.*; MANAHAN, D.T.; U of Southern California; U of Southern California dhedge@usc.edu
Underlying Darwin’s theory of evolution by natural selection are two observations: (1) organisms have excess reproductive capacity and (2) individuals of the same species vary extensively. Some of this phenotypic variation, we now know, is heritable (Phenotype = Genotype + Environment + G×E Interaction), so that, as environment changes, natural selection modifies gene pools and generally improves adaptedness. Unfortunately, these principles of Darwinian biology often appear to be missing from research directed at understanding the potential impact of global change on organisms. Experiments that put wild-caught organisms into different environments, in order to observe physiological or functional genomic responses, have limited power because G and G×E components of phenotypic variance are uncontrolled and poorly sampled. This is a particularly challenging issue for studying how highly fecund marine organisms will respond to ocean change, for example, because (1) the genomes of such organisms are extremely polymorphic, with redundant sets of genes responding to environmental stress; (2) genetic components of variance in complex traits, such as survival and growth, are large and non-linear; and (3) small numbers of wild-caught experimental subjects under-sample the true range of population responses. Well-conceived experiments that manipulate G and most importantly G×E, as well as E, to produce phenotypic contrasts and that integrate genomic, transcriptomic, proteomic, and metabolomic with classical biochemical and physiological approaches are going to be required to understand and to predict the Darwinian biological responses of organisms to global change. A focus on model species with well-developed genetic, genomic, and physiological resources is indicated.
