Две теории биологической эволюции. Гродницкий Д.Л. - 128 стр.

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SUMMARY
This book should be of interest to all biologists, both experts and students, who
are interested in unsolved problems of the evolutionary theory. The existing view of
evolution called the synthetic theory, or neoDarwinism, was formulated in 192030s
(Tschetwerikoff 1926; Haldane 1932; Fisher 1930; Wright 1931; Dobzhansky 1937;
Huxley 1942) and remains the best developed paradigm in theoretical biology. The
synthetic theory combined the Darwinian concept of natural selection with
Mendelian genetics. NeoDarwinism states that genes of organisms accidentally
change (or mutate) in the course of DNA replication at meiosis. Mutations normally
are recessive. Thus, the mutant genes are not expressed phenotypically right after the
change: they are said to remain hidden in genotypes. However, expression of any
gene depends on other genes in the genotype. Hence, the role a new mutant gene
plays in determining the phenotype constantly changes as a consequence of the genic
and chromosomal recombination that occurs at reproduction. Eventually, the recom
bination generates the genic composition in which the mutant gene acquires a phe
notypic expression that can be assessed by natural selection. Whenever the newly
generated phenotype can survive and reproduce (i. e. is adaptive), its genotype is
transferred to the organism’s descendants. Accordingly, a stable change in the gene
pool of a population of organisms is called evolution in the neoDarwinian sense.
Thus, the most important factors causing the evolutionary transformation of organ
isms are genic recombination and natural selection.
Many authors believe that the neoDarwinian paradigm is weakened by not
having a developmental perspective. Hence the recent attempts to incorporate
aspects of developmental biology into the synthetic theory framework (e. g.
McKinney & McNamara 1991; Hall 1992; Jablonka & Lamb 1995; Rollo 1995).
However, some authors hold that developmental biology and neoDarwinism are in
principle incompatible (Shishkin 1992): neoDarwinism assumes there are reliable
genotypephenotype correlations (otherwise it would not be possible to explain evo
lution in the terms of genic frequencies), whereas there are many examples from
developmental biology that indicate the absence of such correlations.
Meanwhile, not withstanding the compatibility of neoDarwinism and develop
mental biology, there are reasons to doubt the adequacy of the synthetic paradigm, as
it makes several false predictions. The first inconsistency involves the rates of evolu
tion: contrary to theory, complex organisms evolve faster than simple ones
(Rasnitsyn, 1987).
Second, the theory states that evolution cannot proceed in the absence of
recombination (Stebbins 1950). Nevertheless, asexuality is the initial condition in
many groups (Maynard Smith 1978), which are no less diverse than those reproduc
ing bisexually (Vavilov 1922). Hence taxa are able to evolve even after they have

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