Nuclear reactors could be built more efficiently using supercomputers to artificially "evolve" designs, say engineers from the US Department of Energy's Oak Ridge National Laboratory in Tennessee. They have found they can speed up the extremely complex process of designing a reactor and generate novel designs from scratch by simulating natural selection. Designing a nuclear reactor normally involves input from various specialists and the resulting structure can be uniquely influenced by this collaborative process. "The design that comes out of this lengthy process is typically sub-optimal," says Louis Qualls, a nuclear systems specialist at Oak Ridge National Laboratory. "If you...