Richard Goldschmidt, an accomplished geneticist of the early twentieth century, argued that Darwin's idea of
evolution via small,
continuous changes might account for changes within a species (
microevolution), but did not explain the appearance of new species or higher taxa (
macroevolution). Rather, he argued, these new species and higher taxa result from drastic reorganizations of the entire
genome. While the results of these reorganizations would almost always be monsters with no chance to survive, on rare occasions, they would would result in
hopeful monsters. These hopeful monsters would then found new species.
While the genetic underpinnings imagined by Goldschmidt have been refuted by modern geneticists, the importance of large changes in evolution is still discussed by evolutionary biologists. For example, later formulations of punctuated equilibrium proposed that evolution has proceeded through large, discontinuous changes.