How does a new species emerge? How about a class or a phylum? Our current evolutionary view is based on the neo-Darwinian synthesis. Several scholars such as De Vries, Goldschmidt, White, Nei, and Kaufmann proposed alternative possibilities, but have never been appreciated. In the current synthesis, reproductive isolation is recognized as the final process of speciation. Instead, I ask readers to imagine that reproductive isolation could be the first step. What would happen if meiotic block were induced by chromosomal rearrangement due to incompatibility in two homologous chromosomes? Then, consider the possibility of the breakpoints of a chromosome creating changes to long range enhancers. Finally, what would happen if a new species took an unoccupied niche which no other species considers livable? Speciation could occur by an expansion of a livable niche while co-existing with other species. In contrast to natural selection, which is based on genetic drift within a single species, once reproductive isolation occurs, no further allelic selection is possible. If a new species can take a niche different from the previous species, no competition is required. ‘Survival of the fittest’ is an illusion in the context of speciation. I recognize that my view is controversial but would provide an alternative view for punctuated equilibrium that is well recognized in fossil records. From this view, we should be able to find more widespread links between large genomic variation and the development of species/class/phylum defining traits.
Richard Goldschmidt "The Material basis of Evolution" (1940) Yale Univ Press
Michael J. D. White "Modes of Speciation" (1978) W.H.Freeman and Company
Masatoshi Nei "Mutation-Driven Evolution" (2013) Oxford Univ Press
Stuart Kauffman "A World Beyond Physics " (2019) Oxford Univ Press
Niles Eldredge and Stephen J. Gould “Punctuated equilibria: An alternative to phyletic gradualism” (1972) "Models in paleobiology", edited by Schopf, TJM Freeman, Cooper & Co, San Francisco.
I would like to thank KS and TN.