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Economic Botany

, Volume 58, Issue 1, pp 5–10 | Cite as

Unconscious selection and the evolution of domesticated Plants

  • Daniel Zohary

Abstract

Two types of selection operate (and complement each other) in plants under domestication: (a) conscious or intentional selection applied by the growers for traits of interest to them; (b) unconscious or automatic selection brought about by the fact that the plants concerned were taken from their original wild habitats and placed in new (and usually very different) human-made or human-managed environments. The shift in the ecology led automatically to drastic changes in selection pressures. Numerous adaptations vital for survival in the wild environments lost their fitness under the new sets of conditions. New traits were automatically selected, resulting in the build-up of characteristic “domestication syndromes,” each fitting the specific agricultural environment provided by the farmer.

The present paper assesses the evolutionary consequences of the introduction of the wild plants into several sets of contrasting farming situations. These include: (a) the type of maintenance applied, whether seed planting or vegetative propagation; (b) the plant organs for which the crop has been grown, whether they are reproductive parts or vegetative parts; (c) the impact of the system of tilling, sowing, and reaping on the evolution of grain crops; (d) the impact of the horticultural environment on fruit crops.

Key Words

Evolution of crop plants unconscious selection origin of domestic traits 

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Literature Cited

  1. Darlington, C. D. 1963. Chromosome botany and the origin of cultivated plants. 2nd ed. Allen and Unwin, London, UK.Google Scholar
  2. —. 1973. Chromosome botany and the origin of cultivated plants. 3rd ed. Allen and Unwin, London, UK.Google Scholar
  3. Darwin, C. 1859. The origin of species. John Murray, London, UK.Google Scholar
  4. —. 1882. The variation of animals and plants under domestication. 2nd ed. John Murray, London, UK.Google Scholar
  5. Hahn, S. K. 1995. Yams. Pages 112–120 in J. Smartt and N.W. Simmonds, eds., Evolution of crop plants, 2nd ed. Longman, Harlow, UK.Google Scholar
  6. Hammer, K. 1984. Das Domestikationssyndrom. Kulturpflanze 32:11–34.CrossRefGoogle Scholar
  7. Hanelt, P. 1986. Pathways of domestication with regard to crop types (grain legumes, vegetables). Pages 179–199 in C. Barigozzi, ed., The origin and domestication of cultivated plants. Elsevier, Amsterdam, The Netherlands.Google Scholar
  8. Harlan, J. R. 1975. Crops and man. American Society of Agronomy, Madison, WI.Google Scholar
  9. —. 1992. Crops and man. 2nd ed. American Society of Agronomy, Madison, WI.Google Scholar
  10. —,J. M. J.de Wet, andE. G. Price. 1973. Comparative evolution of cereals. Evolution 27: 311–325.CrossRefGoogle Scholar
  11. Heiser, C. B. 1988. Aspects of unconscious selection and the evolution of domesticated plants. Euphytica 37:77–81.CrossRefGoogle Scholar
  12. Hillman, G. C., andM. S. Davies. 1990. Measured domestication rates in wild wheat and barley under primitive cultivation and their archaeological implications. Journal of World Prehistory 4:157–222.CrossRefGoogle Scholar
  13. Rindos, D. 1984. The origins of agriculture. Academic Press, San Diego, CA.Google Scholar
  14. Roach, B. T. 1995. Sugarcanes. Pages 160-166 in J. Smartt and N. W. Simmonds, eds., Evolution of crop plants. 2nd ed. Longman,Harlow, UK.Google Scholar
  15. Zohary, D. 1969. The progenitors of wheat and barley in relation to domestication and agricultural dispersal in the Old World. Pages 47–66 in P. J. Ucko and G. W. Dimbleby, eds., The domestication and exploitation of plants and animals. Duckworth, London, UK.Google Scholar
  16. —. 1984. Modes of evolution under domestication. Pages 579–596 in W. Grant, ed., Plant biosystematics. Academic Press, Toronto, Canada.Google Scholar
  17. Zohary, D., andM. Hopf. 2000. Domestication of plants in the Old World. 3rd ed. Oxford University Press, Oxford, UK.Google Scholar
  18. —, andP. Spiegel-Roy. 1975. Beginning of fruit growing in the Old World. Science 187:319–327.PubMedCrossRefGoogle Scholar
  19. —,E. Tchernov, andL. Kolska-Horwitz. 1998. The role of unconscious selection in the domestication of sheep and goats. Journal of Zoology, London 245:129–135.CrossRefGoogle Scholar

Copyright information

© The New York Botanical Garden Press, Bronx, NY 10458-5126 U.S.A 2004

Authors and Affiliations

  • Daniel Zohary
    • 1
  1. 1.Department of Evolution, Systematics and EcologyThe Hebrew UniversityJerusalemIsrael

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