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Table 1 Differences between various punctuational theories and models

From: Microevolutionary, macroevolutionary, ecological and taxonomical implications of punctuational theories of adaptive evolution

Theory and its author The aim Suggested mechanism
Shifting balance theory to explain the ability of species with large subdivided populations cross valleys in adaptive landscape 1. fragmentation of population to small subpopulations where an efficiency of selection is low 2. spreading and fixation of a new allele (that is detrimental when rare) in a subpopulation by drift 3. “Infection” of other subpopulations with individuals with new genotype originated from a successful population and the origination of new populations by these individuals
Wright S. 1932 1
Genetic revolution to explain the role of founder events in speciation 1. change of balanced frequency of alleles in a split-off subpopulation due to sampling effect 2. selection for alleles with best effect on fitness instead of best-cooperator alleles
Mayr E. 1954 2
Founder-flush model to explain the role of founder events in speciation 1. sampling effect due to rapid one-step reduction of a population size, 2. expansion of the population in an open uninhibited ecological niche, which relaxes all forms of selection allowing for surviving recombinants and mutants with suboptimal phenotypes (crossing valleys in the adaptive landscape) 3. reaching (or overshooting) the carrying capacity of a locality and the restoration of selection
Carson H.L. 1968 3
Genetic transilience model to explain the role of founder events in speciation 1. sampling effect due to rapid one-step reduction of a population or to hybridization, 2. an increase of the amount of selectable genetic variability due to transformation of nonadditive (and therefore nonselectable) genetic variability to additive genetic variability and by higher survival probability for carriers of new mutations in the expanding population, which increases responsiveness of the population to selection 3. restoration of the population size limitation and selection
Templeton A.R. 1980 4
Punctuated equilibrium to explain the discontinuous nature of evolution and coincidence of anagenetic and cladogenetic events various mechanisms suggested by Eldredge and Gold, including peripatric speciation and strong selection in unusual conditions on the periphery of the species’ range, peripatric speciation accompanied by genetic revolution, sorting (according to Futuyma7, without speciation, any evolutionary novelty is reversible due to gene flow), etc.
Eldredge N. 1971 5
Frozen plasticity theory to explain why old species are microevolutionarily elastic and macroevolutionarily frozen, how frozen species can turn plastic, and the continuously decreasing rate of macroevolution 1. most polymorphism existing in an old species is sustained in it’s gene pool by frequency dependent selection creating interconnected network resistant to changes of allele frequencies, 2. most new (potentially useful) alleles are captured in this elastic network of alleles due to pleiotropy and its effect on (stabilized) frequencies of old alleles, 3. in small split-off populations balancing on the edge of extinction for several generations, a decrease in strength of selection, including frequency dependent selection, will occur, and most genetic polymorphism will disappear due to drift 4. after expansion of population size, now large genetically uniform population turns evolutionary plastic – new advantageous mutations can spread in the network-free population by selection 5. traits resistant to thawing accumulate in the gene pool by sorting on the basis of stability 6. accumulation of permanently frozen traits by the mechanism of sorting on the basis of stability in particular clades during macroevolution
Flegr J. 1998 6
  1. The Genetic Revolution model implicitly and the Frozen Plasticity model explicitly suggest that frequency-dependent selection plays an important role in stabilization of the gene pool of a species. Therefore, according to these two theories, macroevolutionary frozen species are microevolutionarily elastic. According to the Shifting Balance theory, the Founder Flush and the Genetic Transilience models, they are microevolutionary frozen, i.e. they have significantly reduced plasticity in comparison with their plastic state. According to Futuyma’s sorting model, macroevolutionarily frozen species can be microevolutionarily plastic. 1 (Wright 1932), 2 (Mayr 1954), 3 (Carson 1968), 4 (Templeton 1980), 5 (Eldredge 1971), 6 (Flegr 1998), 7 in (Gould 2002), p. 77. In fact, the Punctuated equilibrium theory in its current form was published in 1972 by Eldredge and Gould (Eldredge and Gould 1972) and the Frozen plasticity theory in 2008 (Flegr 2008) and 2010 (Flegr 2010) by Flegr.