478 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1956 



mongrelize and, under the hand of selection, evolve as rapidly into 

 new paths as did the salvias in the abandoned olive orchard. What 

 must have happened when the first land vertebrates at last arrived 

 on continents whose vegetation had no experience of such beasts? 

 What occurred when the giant reptiles of the Mesozoic churned like 

 gigantic bulldozers through the ferny swamps of that period? Must 

 not the plants of those periods have gone through the same general 

 experiences as are now facing the adenostomas of the California 

 chaparral ? 



Man has been a major force in the evolution of the plants and ani- 

 mals that accompany him around the world, in the midst of which 

 he largely spends his days. The detailed study of this process (1) 

 should illuminate for us the course of evolution in prehuman times; 

 (2) should be as well one of our truest guides to the history of pre- 

 historic man; and (3), most importantly, should enable us at last to 

 understand and eventually to control the living world around us. 



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1946. Cytology of cereals, II. Bot. Rev., vol. 12, No. 5, pp. 255-334. 

 Anderson, Edgar 



1949. Introgressive hybridization. 109 pp. New York. 

 1952. Plants, man, and life. 245 pp. Boston. 



1954. Introgression in Adenostoma. Ann. Missouri Bot. Garden, vol. 41, pp. 

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 Anderson, Edgar, and Anderson, Burton R. 



1954. Introgression of Salvia apiana and Salvia mellifera. Ann. Missouri 

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1954. Hybridization as an evolutionary stimulus. Evolution, vol. 8, No. 4, 

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DOBZHANSKY, TH. 



1949. Observations and experiments on natural selection in Drosophila. 



In Bonnier, Gert, and Larsson, Robert (eds.), Proc. Eighth 



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1938. The California salvias. A review of Salvia, Section Audibertia. 



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1942. The centers of distribution of the chaparral and coastal sage as- 

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1949. Study in the evolution of the sunflower species Eelianthus annuus 

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