Rapid modes of evolution

Rapid modes of evolution have been proposed by several notable biologists ever since Charles Darwin proposed his theory of evolutionary descent by natural selection. In his classic volume "On the Origin of Species" (1859), Darwin famously and eloquently stressed the gradual nature of descent, writing:

:It may be said that natural selection is daily and hourly scrutinizing, throughout the world, every variation, even the slightest; rejecting that which is bad, preserving and adding up all that is good; silently and insensibly working, whenever and wherever opportunity offers, at the improvement of each organic being in relation to its organic and inorganic conditions of life. We see nothing of these slow changes in progress, until the hand of time has marked the long lapses of ages, and then so imperfect is our view into long past geological ages, that we only see that the forms of life are now different from what they formerly were. (1859)

Other biologists, for a variety of reasons, have disagreed with Darwin's interpretation of evolutionary change, and have argued for a different picture, drawing upon stable biological continuity which is then interrupted by rapid speciation. Some theories characterize this speciation cladistically (by splitting) or by phyletic transformation (anagenesis).

Evolutionary developmental biology

Recent work in developmental biology has identified dynamical and physical mechanisms of tissue morphogenesis that may underlie such abrupt morphological transitions. Consequently, consideration of mechanisms of phylogenetic change that are actually (not just apparently) non-gradual is increasingly common in the field of evolutionary developmental biology, particularly in studies of the origin of morphological novelty. A description of such mechanisms can be found in the multi-authored volume "Origination of Organismal Form".

Bibliography

*Darwin, C. (1859) "On the Origin of Species" London: Murray.
*Eldredge, N. and S. J. Gould (1972). [http://www.blackwellpublishing.com/ridley/classictexts/eldredge.asp "Punctuated equilibria: an alternative to phyletic gradualism"] In T.J.M. Schopf, ed., "Models in Paleobiology". San Francisco: Freeman, Cooper and Company, pp. 82-115.
*Goldschmidt, R. (1940) "The Material Basis of Evolution". New Haven, Conn.: Yale University Press.
*Gould, S. J. (1977) [http://www.evolutionary.tripod.com/gould_nh_86_6_22-30.html "The Return of Hopeful Monsters"] Natural History 86 (June/July): 22-30.
*Gould, S. J. (2002) "The Structure of Evolutionary Theory". Cambridge MA: Harvard Univ. Press.
*Müller, G. and S. Newman, eds. (2003) "". Cambridge: The MIT Press.
*Schindewolf, O. H. (1963) Neokatastrophismus? "Zeits. Deutsch. Geol. Res." 114: 430-435.
*cite book| author=West-Eberhard, M. J. |year=2003 | title=Developmental Plasticity and Evolution | publisher=Oxford University Press

ee also

*Evolution
*Evolutionary developmental biology
*Hopeful Monster theory
*Otto Schindewolf
*Punctuated equilibrium
*Quantum evolution
*Richard Goldschmidt
*Saltationism