Résumé
The shape of animals is established during their embryonic development. As a consequence, understanding which mechanisms drive embryogenesis is crucial for understanding the evolution of morphologies. The last 30 years has shown that gene expression has a major role in regulating embryonic development. More recently, the way these genes and their regulators interact has been conceptualized as gene regulatory networks or GRNs that thus describe the underlying logic that drives development. However, until recently, the lack of tools available for non-model organisms has limited the understanding of their evolution. Thanks to the new discoveries and new techniques that have arisen in the last 10 years, studying and manipulating GRNs in depth is now possible in model and non-model organisms, expanding our resources to understand morphological evolution. In this chapter, we review current knowledge about how the evolution of GRNs can generate variation. We focus on the recent advances in techniques that allow the study of GRNs in different organisms. These discoveries are crucial not only to understand how species evolve and get their shape but also to understand how defects in the developmental program could lead to morphological defects in humans.