Anderson • Cytotaxonomy 



241 



Edgar Anderson 

 Cytotaxonomy 



Reprinted with the permission of the author 

 from Chapter 4 of Plants, man and hfc. 

 Boston, Little, Brown and Co., 1952. 



Cytologists are microscopists; they 

 study plant and animal cells under 

 high magnification. Their commonest 

 technique has been to take some easily 

 accessible portion of a plant or animal 

 (in plants it is frequently the tip of a 

 rapidly growing root) and immerse it 

 in various successive solutions to pre- 

 serve and stain its essential features 

 and then to study these pickled remains 

 enlarged a thousand times or more 

 under the microscope. Who would 

 have supposed that men of this sort 

 would have new clues to the origin and 

 history of the plants so closely asso- 

 ciated with man? Yet it is thev who, 

 though generally ignorant of prehistory, 

 knowing little or nothing about tax- 

 onomy and usually so scornful of its 

 innate conservatism that they did not 

 wish to learn any more, have made the 

 most startling discoveries in this field 

 in the last few decades. It is they who 

 have produced exact evidence as to 

 which kinds of primitive grasses were 

 combined in the Stone Age to produce 

 our wheats. It is they who can prove 

 without the shadow of a doubt that the 

 Asiatic cottons (perhaps the wild ones, 

 perhaps the cultivated ones) somehow 



crossed the Pacific or traveled around 

 it by slow stages and played a definite 

 role in establishing American culti- 

 vated and weed cottons. It is thev who 

 narrowed down the problem of where 

 tobacco might have originated and ex- 

 plained such modern miracles as the 

 loganberr}'. Nor have thev been con- 

 tent merely to launch fantastic hypoth- 

 eses; by further developments of 

 their techniques and with the help of 

 plant breeders thev have been able to 

 re-enact these hypothetical histories 

 and actually (as we shall see) to re- 

 create such crop plants de noyo from 

 their primitive ancestors. Brilliant as 

 this new evidence is, it tells us about 

 only one or two details in the origin 

 and development of certain crops and 

 weeds— nothing about the rest of their 

 histories, and nothing at all for many 

 other crops and weeds. If we revert to 

 our previous conception of the history 

 of these important plants as a complex 

 detective story with many kinds of 

 clues, then cytology furnishes a dis- 

 connected set of brilliant flashlight 

 photographs, illustrating with tanta- 

 lizing clarity just one or two phases of 

 the mystery. . . , 



