Rapid evolution in nature

Typically perceived as a slow and imperceptible process, biological evolution by natural selection can indeed be rapid in natural populations. Environmental upheaveal caused by human activity (climate changes, habitat loss, pollution, introduction of species in new areas) could accelerate this process (see this book for an overview). By changing the frequency distribution of phenotypes (i.e. organisms' traits, such as body size), rapid evolution can alter fundamental ecological processes such as population,predator-prey or community dynamics that, in turn, produce feedback effects on natural selection (see here). Such an eco-evolutionary dynamics can accelerate or impede the biological evolution of populations in response to selective pressures. The possibility to detect evolution over just a few years or decades raises several fundamental questions: what is the evolutionary potential of populations over short timescales? How heterogeneous are evolutionary responses across populations facing similar environmental conditions? How evolutionary change in one trait modifies selection on other traits? To answer this kind of questions, we study the process of biological evolution in contemporary human populations using population registers.