Loss of allelic diversity in species of hybrid origin


Species of hybrid origin support their population as a rule by cloning. Switching over of any bisexual organism to propagation by means of parthenogenesis, gynogenesis, androgenesis (or other kind of apomictic reproduction without regular recombination, which usually accompanies change of generations in bisexual species) leads to rapid decrease of genetic polymorphism. Long-term cloning transforms the polymorphic population or entire species into a mixture of only a few clones, composed of genetically identical individuals. owing to selection in favour of heterozygotes or due to hybrid origin, natural clonal populations commonly are of high heterozygosity. Selection, genotypic uniformity and high heterozygosity often give to clonal race or species selective advantages, but at the same time they inevitably result in loss of most of alleles. Inasmuch as new forms, reproductively isolated from parental species, are products of hybridization of only a small number of individuals, which succeed in overcome the interspecies barrier, the hybridization itself also plays role of a very narrow bottle neck. The well established opinion that recombination and allelic diversity are necessary conditions for successful evolution on the basis of gene frequency changes, comes now into contradiction with the available data concerning the polyploid and, probably, hybrid origin of many groups of flowering plants and vertebrate animals.

Sergey D Grebelnyi

Zoological Institute RAS, Saint-Petersburg, RF

Email: actinia@zin.ru

  1. Боркин Л. Я. и Даревский И. С., 1980. Сетчатое (гибридогенное) видообразование у позвоночных//Журн. общ. биол. Т. 41, № 4. С. 485-506.
  2. Васецкий С. Г., 1977. Мейотические деления//Современные проблемы оогенеза. М.: Наука. С. 145-173.
  3. Грант В., 1984. Видообразование у растений. М.: Мир, 528 с. (Англ. изд. -Grant V., 1971. Plant speciation. London, 436 p.; 2nd edition. New York: Columbia Univ. Press, 1981. 536 p.)
  4. Гребельный С. Д., 2005. Много ли на свете клональных видов. Часть первая. Отличие клональных форм от обычных двуполых видов//Журн. зоологии беспозвоночных. Т. 2, № 1. С. 79-102.
  5. Гребельный С. Д., 2008. Клонирование в природе. Роль остановки генетической рекомбинации в формировании фауны и флоры. Санкт-Петербург, 287 с.
  6. Кайданов Л. З., 1996. Генетика популяций. М.: Высшая школа, 320 с.
  7. Майр Э., 1968. Зоологический вид и эволюция. М.: Мир, 597 с. (Англ. изд. -Mayr E., 1963. Animal Speciation and Evolution. Cambridge (Mass.): Belknap Press of Harvard University Press.)
  8. Мэйнард-Смит Дж., 1981. Эволюция полового размножения. М.: Мир, 271 с. (Англ. изд. -Maynard-Smith J., 1978. The evolution of sex. Cambridge: Cambridge Univ. Press.)
  9. Оно С., 1973. Генетические механизмы прогрессивной эволюции. М.: Мир, 227 с. (Англ. изд. -Ohno S., 1970. Evolution by gene duplication. Berlin-Heidelberg-New York: Springer-Verlag.)
  10. Цвелев Н. Н., 2005. Проблемы теоретической морфологии и эволюции высших растений. М. -СПб: Товарищество научных изданий «КМК», 407 с.
  11. Dobzhansky Th., 1937 (1st. ed.), 1941 (2nd. ed.), 1951 (3rd. ed.) Genetics and the origin of species. New York: Columbia University Press., 1st. ed. 364 p., 2nd ed. 446 p., 3rd. ed. 364 p.
  12. Gallardo M. H., Kausel G., Jimйnez A., Bacquet C.et al., 2004. Whole-genome duplications in South American desert rodents (Octodontidae)//Biol. J. Linn. Soc. Vol. 82. P. 443-451.
  13. Kobel H. R., 1996. Allopolyploid speciation//Eds. Tinsley R. C. and Kobel H. R. The biology of Xenopus. Symposia of the Zoological Society of London. N 68. P. 391-401.
  14. Spring J., 2003. Major transitions in evolution by genome fusions: from prokaryotes to eukaryotes, metazoans, bilaterians and vertebrates//J. of Structural and Functional Genomics. Vol. 3. P. 19-25.
  15. Suomalainen E., 1969. Evolution in parthenogenetic Curculionidae//Eds. Dobzhansky Th., Hecht M. and Steere W. Evolutionary Biology. Vol. 3. P. 261-296.
  16. Timofйeff-Ressovsky N. W., 1939. Genetik und Evolution (Bericht eines Zoologen)//Zeitschrift fьr induktive Abstammungs-und Vererbungslehre. Bd. 76. S. 158-218.


Abstract - 252

PDF (Russian) - 189


Copyright (c) 2009 Grebelnyi S.D.

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.