A SPATIALLY EXPLICIT STOCHASTIC MODEL DEMONSTRATES THE FEASIBILITY OF WRIGHT'S SHIFTING BALANCE THEORY

Recently there has been a resurgence of theoretical papers exploring Wright's Shifting Balance Theory (SBT) of evolution. The SBT explains how traits which must pass through an adaptive valley may evolve in substructured populations. It has been suggested that Phase III of the SBT (the spread of new advantageous traits through the populations) proceeds only under a very restricted set of conditions. We show that Phase III can proceed under a much broader set of conditions in models that properly incorporate a key feature of Wright's theory: local, random migration of discrete individuals.

[1]  S. Levin,et al.  Mathematical and Computational Challenges in Population Biology and Ecosystems Science , 1997, Science.

[2]  Burt,et al.  Natural selection in the wild. , 2000, Trends in ecology & evolution.

[3]  M. Slatkin.  Gene flow and genetic drift in a species subject to frequent local extinctions. , 1977, Theoretical population biology.

[4]  N. Barton,et al.  Group selection and the shifting balance , 1993 .

[5]  S. Karlin,et al.  A second course in stochastic processes , 1981 .

[6]  Sydney Smith,et al.  Darwin's biological work—some aspects reconsidered. , 1960 .

[7]  R. Durrett,et al.  The Importance of Being Discrete (and Spatial) , 1994 .

[8]  R. Lande,et al.  The fixation of chromosomal rearrangements in a subdivided population with local extinction and colonization , 1985, Heredity.

[9]  Nicholas H. Barton,et al.  Adaptation and the shifting balance , 1993 .

[10]  N. Barton,et al.  PERSPECTIVE: A CRITIQUE OF SEWALL WRIGHT'S SHIFTING BALANCE THEORY OF EVOLUTION , 1997, Evolution; international journal of organic evolution.

[11]  S. Gavrilets.  ON PHASE THREE OF THE SHIFTING‐BALANCE THEORY , 1996, Evolution; international journal of organic evolution.

[12]  Nicholas H. Barton,et al.  Speciation and the “shifting balance” in a continuous population , 1987 .

[13]  J. Crow,et al.  PHASE THREE OF WRIGHT'S SHIFTING-BALANCE THEORY. , 1990 .

[14]  S. Wright.  Surfaces of Selective Value Revisited , 1988, The American Naturalist.

[15]  M. Wade,et al.  EXTINCTION AND RECOLONIZATION: THEIR EFFECTS ON THE GENETIC DIFFERENTIATION OF LOCAL POPULATIONS , 1988, Evolution; international journal of organic evolution.

[16]  N. Barton,et al.  The frequency of shifts between alternative equilibria. , 1987, Journal of theoretical biology.

[17]  Patrick C Phillips,et al.  PEAK SHIFTS AND POLYMORPHISM DURING PHASE THREE OF WRIGHT'S SHIFTING‐BALANCE PROCESS , 1993, Evolution; international journal of organic evolution.