6 Eco-Evo-Devo: The Time Has Come Ehab Abouheif, Marie-Julie Favé, Ana Sofia Ibarrarán-Viniegra, Maryna P. Lesoway, Ab Matteen Rafiqi, and Rajendhran Rajakumar Abstract The major goal of ecological evolutionary developmental biology, also known as “eco-evo-devo,” is to uncover the rules that underlie the interactions between an organism’s environment, genes, and development and to incorporate these rules into evolutionary theory. In this chapter, we discuss some key and emerging concepts within eco-evo-devo. These concepts show that the environment is a source and inducer of genotypic and phenotypic variation at multiple levels of biological organization, while development acts as a regulator that can mask, release, or create new combinations of variation. Natural selection can subsequently fix this variation, giving rise to novel phenotypes. Combining the approaches of eco-evo-devo and ecological genomics will mutually enrich these fields in a way that will not only enhance our understanding of evolution, but also of the genetic mechanisms underlying the responses of organisms to their natural environments. Keywords Evodevo • Evolution • Ecology • Stochastic variation • Robustness • Environmental stress • Developmental recombination • Genetic accommodation • Genetic assimilation • Ancestral developmental potential • Social interactions • Epigenetics • Developmental plasticity • Polyphenism • Ecoevodevo E. Abouheif () • M.-J. Favé • A.S. Ibarrarán-Viniegra A.M. Rafiqi • R. Rajakumar Department of Biology, McGill University, 1205 avenue Docteur Penfield, Montreal, QC H3A 1B1, Canada e-mail: ehab.abouheif@mcgill.ca M.P. Lesoway Department of Biology, McGill University, 1205 avenue Docteur Penfield, Montreal, QC H3A 1B1, Canada Smithsonian Tropical Research Institute, Apartado Postal 0843-03092, Panamá, República de Panamá 6.1 Introduction The time seems to have come when we need to take into account two further aspects of the evolutionary mechanism. In the first place, natural selective pressures impinge not on the hereditary factors themselves, but on the organisms as they develop from fertilized eggs to reproductive adults. We need to bring into the picture not only the genetic system by which hereditary information is passed on from one generation to the next, but also C.R. Landry and N. Aubin-Horth (eds.), Ecological Genomics: Ecology and the Evolution of Genes and Genomes, Advances in Experimental Medicine and Biology 781, DOI 10.1007/978-94-007-7347-9__6, © Springer ScienceCBusiness Media Dordrecht 2014 107