SYMBIOSIS AND THE BIOLOGY OF FOOD 259 



and in so doing there is a marked tendency to upset the physio- 

 logical balance of the plant and also to open the door to the 

 spread of disease. 



That domestication of the animal is very similar in its 

 ill effects to slavery in the human world may be gleaned from 

 the following : Dr. W. P. Pycraft tells us, with regard to the 

 " grey," or " grey-lag " goose, the only species indigenous to 

 the British Islands, that in the good old days this species bred in 

 numbers in the Fen country, where the young were caught by 

 the score, and added to the vast flocks of domesticated geese 

 that proved so valuable a property to the dwellers in these 

 rheumatic regions. Five times a year they were plucked 

 alive ! Dr. Pycraft goes on to say that some hold that it is 

 largely, at any rate, to this barbarous practice that we owe 

 our breeds of white geese to-day. " The pigmentation of a 

 feather," he says, " is a very variable quantity, and is easily 

 upset. A coloured feather plucked out of a living bird is 

 occasionally replaced by a white one, and, when this plucking 

 is repeated five times a year, and for several years, nature's 

 colour-box becomes exhausted. Thus a white goose is soon 

 * made ' ; and it would almost seem that in a few generations 

 the pathological condition became transmitted to the off- 

 spring. Whether the white geese so prized by the Romans 

 were produced in this manner, or by the selection of variations 

 in the direction of whiteness till success crowned their efforts, 

 is not known." 



We are further told : " The * grey-lag ' goose gained its 

 qualifying ' lag ' because it was the one, of all the wild geese 

 which winter with us, which * lagged ' behind, after the rest 

 had betaken themselves to the more northern breeding quarters. 

 This display of confidence was most shockingly abused, for we 

 made of them bond-slaves, and bade them first make feathers 

 from bare and bleeding bodies, and later bad livers for pate de 

 foie gras, and fat, unwieldy bodies for Michaelmas and Christ- 

 mas feasts." 



" Exquisite as are the results of civilisation," says Prof. 

 R. C. Punnett in his Mendelism, " it is by the degradation of 

 the wild that they have been brought about." And he goes on 

 to question : " How far are we justified in regarding this as a 

 picture of the manner in which evolution works ? " 



My answer is that, inasmuch as domestication induces 

 serious degrading effects, it represents the inverse of progressive 

 evolution, which, per contra, evinces a slow and gradual up- 

 building. There are, of course, different degrees, and also 

 different methods of domestication, and in some cases there is 

 an actual gain of valuable factors, compensating to some extent 

 for the losses in other directions. It is a natural process. 



