hierarchies, primitives, and modularity, at all levels of sensorimotor and social structures, can be formed and leveraged during development. This is deeply linked with the problem of the emergence of symbols, sometimes referred to as the "symbol grounding problem" when it comes to language acquisition. Actually, the very existence and need for symbols in the brain are actively questioned, and alternative concepts, still allowing for compositionality and functional hierarchies are being investigated. During biological epigenesis, morphology is not fixed but rather develops in constant interaction with the development of sensorimotor and social skills. The development of morphology poses obvious practical problems with robots, but it may be a crucial mechanism that should be further explored, at least in simulation, such as in morphogenetic robotics. Another open problem is the understanding of the relation between the key phenomena investigated by developmental robotics (e.g., hierarchical and modular sensorimotor systems, intrinsic/extrinsic/social motivations, and open-ended learning) and the underlying brain mechanisms. Similarly, in biology, developmental mechanisms (operating at the ontogenetic time scale) interact closely with evolutionary mechanisms (operating at the phylogenetic time scale) as shown in the flourishing "evo-devo" scientific literature. However, the interaction of those mechanisms in artificial organisms, developmental robots, in particular, is still vastly understudied. The interaction of evolutionary mechanisms, unfolding morphologies and developing sensorimotor and social skills will thus be a highly stimulating topic for the future of developmental robotics. Main journals IEEE Transactions on Cognitive and Developmental Systems (previously known as IEEE Transactions on Autonomous Mental Development): https://cis.ieee.org/publications/t-cognitive-and-developmental-systems Main conferences International Conference on Development and Learning: http://www.cogsci.ucsd.edu/~triesch/icdl/ Epigenetic Robotics: https://www.lucs.lu.se/epirob/ ICDL-EpiRob: http://www.icdl-epirob.org/ (the two above joined since 2011) Developmental Robotics: http://cs.brynmawr.edu/DevRob05/ The NSF/DARPA funded Workshop on Development and Learning was held April 5–7, 2000 at Michigan State University. It was the first international meeting devoted to computational understanding of mental development by robots and animals. The term "by" was used since the agents are active during development. See also Evolutionary developmental robotics Robot learning References External links Technical committees IEEE Technical Committee on Cognitive and Developmental Systems (CDSTC), previously known as IEEE Technical Committee on Autonomous Mental Development, https://cis.ieee.org/technical-committees/cognitive-and-developmental-systems-technical-committee IEEE Technical Committee on Cognitive Robotics, https://www.ieee-ras.org/cognitive-robotics IEEE Technical Committee on Robot Learning, https://www.ieee-ras.org/robot-learning/ Academic institutions and researchers in the field Lund University Cognitive Science - Robotics Group Cognitive Development Lab, University of Indiana, US Michigan State University – Embodied Intelligence Lab Inria and Ensta ParisTech FLOWERS team, France: Exploration,