"New concepts and information from molecular, developmental biology, systematics, geology and the fossil record of all groups of organisms, need to be integrated into an expanded evolutionary synthesis. These fields of study show that large-scale evolutionary phenomena cannot be understood solely on the basis of extrapolation from processes observed at the level of modern populations and species. Patterns and rates of evolution are much more varied than had been conceived by Darwin or the evolutionary synthesis, and physical factors of the earth's history have had a significant, but extremely varied, impact on the evolution of life." (Carroll, Robert L. [Curator of Vertebrate Paleontology, Redpath Museum, McGill University, Montreal, Canada], "Towards a new evolutionary synthesis," Trends in Ecology and Evolution, 2000, Vol. 15, pp.27-32, p.27)
"The changes within a population have been termed microevolution, and they can indeed be accepted as a consequence of shifting gene frequencies. Changes above the species level-involving the origin of new species and the establishment of higher taxonomic patterns- are known as macroevolution. The central question of the Chicago conference was whether the mechanisms underlying microevolution can be extrapolated to explain the phenomena of macroevolution. At the risk of doing violence to the positions of some of the people at the meeting, the answer can be given as a clear, No." (Lewin, Roger [biochemist, former editor of New Scientist and science writer], "Evolutionary- Theory Under Fire: An historic conference in Chicago challenges the four-decade long dominance of the Modern Synthesis," Science, Vol. 210, 21 November 1980, pp.883-887, p.883).
"Darwin's proposal carries a more general message for contemporary discussions of macroevolution, namely that microevolution alone cannot explain macroevolution." (David N. Reznick and Robert E. Ricklefs, "Darwin's bridge between microevolution and macroevolution." Nature 457:837,838,841, Feb. 12, 2009)
"Evolutionary biologists have long sought to understand the relationship between microevolution (adaptation), which can be observed both in nature and in the laboratory, and macroevolution (speciation and the origin of the divisions of the taxonomic hierarchy above the species level, and the development of complex organs), which cannot be witnessed because it occurs over intervals that far exceed the human lifespan. . . . [from the abstract] "Macroevolution posed a problem to Darwin because his principle of descent with modification predicts gradual transitions between small-scale adaptive changes in populations and these larger-scale phenomena, yet there is little evidence for such transitions in nature. Instead, the natural world is often characterized by gaps, or discontinuities. One type of gap relates to the existence of 'organs of extreme perfection', such as the eye, or morphological innovations, such as wings, both of which are found fully formed in present-day organisms without leaving evidence of a transition between them. These discontinuities, plus the discontinuous appearance and disappearance of taxa in the fossil record, form the modern conceptual divide between microevolution and macroevolution. . . . "Most evolutionary biologists think that Darwin explained macroevolution simply as microevolution writ large. In fact, Darwin had rather more to say about the relationship between microevolution and macroevolution and invoked additional principles to define it. . . .
"Darwin's proposal carries a more general message for contemporary discussions of macroevolution, namely that microevolution alone cannot explain macroevolution." (David N. Reznick and Robert E. Ricklefs, "Darwin's bridge between microevolution and macroevolution." Nature 457:837,838,841, Feb. 12, 2009)
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