The "speed" of evolution is influenced by a multitude of things, time between generations and number of offspring being two of the major ones. For species like

The "speed" of evolution is influenced by a multitude of things, time between generations and number of offspring being two of the major ones. For species like frogs where generations are quick and tad poles are plenty, there's a lot of shots in the dark for evolution to work with so it can happen quickly. For species like humans that take like a fifth of a century per generation and only really shove out 1 or 2 offspring and have a large steady population for genes to diffuse through, the process is a multi-millennia affair. Fruit flies in a jar iterate fast enough if you want to try playing god for a while.