Variation & Evolution of the nervous system

Without understanding the evolution of the nervous system, we cannot understand ourselves as a species, and without understanding how small genetic differences among us affect our brains, we cannot fully appreciate what makes us individuals. At NeuroPSI, several groups focus on the evolution of senses, brains and behaviours. We are interested in the developmental and genetic mechanisms that shape the unique brain anatomy and function resulting from millions of years of evolution and random variations, and how this enables animals to inhabit diverse and ever-changing ecological niches.

What is the evolutionary developmental toolkit, the set of tiny or big differences in embryonic development that control the size, the structure, the connectivity and the organization of animal brains and sensory organs? How are these differences encoded in the genomes? What makes each individual unique? Why do brains, in some species but not others, grow throughout life and have special regenerative capacities fueled by the presence of abundant stem cells? How many ways are there to build neural circuits that will serve the same functions? What is the contribution of adaptive selection and the contribution of random genetic drift in shaping brains and behaviors?

A number of groups from the DECS and CNN departments at NeuroPSI compare the nervous systems of closely related species of flies, fishes and amphibians, or look for functional and structural similarities and differences between more distantly related groups such as fishes, birds and mammals. Their aim is to unravel the developmental constraints on brain and eye morphogenesis, the mechanisms for the generation of neuronal and anatomical diversity, the atypical and attractive regenerative properties of stem cells, or the principles of emergence of exquisite sensory specializations and executive functions. These fundamental questions have fascinated both biologists and the public ever since the work of Charles Darwin or Nikolas Tinbergen. Furthermore, understanding the astonishing diversity of morphologies, developmental mechanisms and neural processes at work in different species, or even among individuals in a single species, will also reveal secrets and resources that evolution discovered for repairing brains and keeping them healthy.