ISSN 10674136, Russian Journal of Ecology, 2009, Vol. 40, No. 5, pp. 305–313. © Pleiades Publishing, Ltd., 2009.
Original Russian Text © V.N. Bol’shakov, T.I. Moiseenko, 2009, published in Ekologiya, 2009, No. 5, pp. 323–332.
Environmental pollution is now a major factor
affecting animal populations. Examples showing that
animals respond to anthropogenic pollution by active
adaptive and microevolutionary transformations have
become increasingly frequent in recent publications
(Braginskii et al., 1971; Kolchinskii, 1990; Bol’shakov
et al., 1991; Bezel’ et al., 1994; Newman, 1995;
Chesser and Sugg, 1996; Staton et al., 2001; Hauser
et al., 2003; Bezel’, 2006; and others). Thus, environ
mental pollution provides us with a unique model for
studying the evolutionary process at work (Dobzhan
Bol’shakov (1991) noted that, although economic
activities change the conditions of animal life, they are
by mo means aimed at altering the pattern of natural
evolution; nevertheless, they have a considerable
effect on many aspects of the evolutionary process,
primarily at the level of microevolution. The evolution
of populations under changing environmental condi
tions may proceed rapidly and dramatically (Malvey
and Diamond, 1996). However, no generalizations on
this problem have been made in the international liter
ature devoted to anthropogenic evolution. Industrial
melanism and acquired tolerance to pesticides in
insects are the most popular examples cited as evi
dence of anthropogenic evolution. However, the liter
ature on genetic adaptation in living organisms and the
evolution of their tolerance to toxic exposure is abun
dant and difficult to review in a single paper.
A number of studies have been performed to ana
lyze and predict how changes occurring in populations
under the impact of toxic agents may reflect on their
genetic diversity (Bol’shakov et al., 1991; Newman,
1995; Bickham et al., 2000; Staton et al., 2001; Hauser
et al., 2003; and others). The main conclusion is that
toxic pollution will lead to a gradual loss of genetic
diversity, on the one hand, and that the toxic agent will
serve as a factor of selection in favor of individuals with
the highest level of tolerance to toxic exposure.
The purpose of this study is to formulate the idea of
how changes in the population exposed to a toxic fac
tor may reflect on its genetic diversity and what conse
quences the selective pressure of environmental pollu
tion factor may have.
SELECTION FOR TOLERANCE
Despite living in a polluted environment, many
organisms have proved to be capable of successful
reproduction, development, and growth. Tolerance
may be defined as the ability of certain individuals to
withstand exposure to the concentrations of toxic
agents that are harmful or lethal to other individuals
(Chesser and Sugg, 1996). Selection will proceed in
favor of most tolerant individuals, i.e., those capable
of activating their intrinsic mechanisms of survival,
including detoxification systems.
Anthropogenic Evolution of Animals:
Facts and Their Interpretation
V. N. Bol’shakov
and T. I. Moiseenko
Institute of Plant and Animal Ecology, Ural Division, Russian Academy of Sciences,
ul. Vos’mogo Marta 202, Yekaterinburg, 620144 Russia;
Institute of Water Problems, Russian Academy of Sciences,
ul. Gubkina 3, Moscow, 119991 Russia;
Received March 26, 2009
—Problems concerning microevolutionary transformations in animal populations are considered.
It is shown that genetic variation is the main factor providing the basis for adaptation to environmental
changes, including toxic pollution. The selection pressure of a toxic factor gives an advantage in survival to
more resistant genotypes in animal populations, which eventually leads to the reduction of their genetic diver
sity and potential for adaptation to other natural or anthropogenic stress factors. Microevolutionary transfor
mations follow the pattern of
selection, i.e., occur in favor of smaller, earlier maturing individuals capable
of expending a greater proportion of their energy resources for reproduction.
: microevolution, population, genetic diversity.