Shifting balance theory Shifting balance theory The shifting balance theory is a theory of evolution proposed in 1932 by Sewall Wright, suggesting that adaptive evolution may proceed most quickly when a population divides into subpopulations with restricted gene flow. The name of the theory is borrowed from Wright's metaphor of fitness landscapes (evolutionary landscapes), attempting to explain how a population may move across an adaptive valley to a higher adaptive peak. According to the theory, this movement occurs in three steps: Although shifting balance theory has been influential in evolutionary biology, inspiring the theories of quantum evolution and punctuated equilibrium, little empirical evidence
Evolutionary Theory (journal) Evolutionary Theory (journal) Leigh Van Valen was an evolutionary biologist that was notable for writing a multitude of scientific papers – roughly 300 over the course of his lifetime. Some of his most important theories included the Red Queen hypothesis which had been rejected by many respectable journals of the time. Van Valen began and published the peer reviewed journal : "Evolutionary theory" with its first issue in July 1973. The very first article in "Evolutionary Theory" was written by Van Valen and titled “A New Evolutionary Law” – notably his most famous paper where he states his Red Queen