The Making of Species 



THE COLOURING OF FLOWERS AND FRUITS 



Extremely interesting though the subject be, 

 we are unable to consider at length the generally 

 accepted theory that the colour markings and 

 perfumes of wild flowers are the result of the 

 unconscious selection exercised by insects. 



While not denying that many flowers profit by 

 their colouring, that these colours may sometimes 

 serve to attract the insects, by means of which 

 cross-fertilisation is effected, we are not prepared 

 to go to the length of admitting that all the 

 colours, etc., displayed by flowers and floral 

 structures are due to the unconscious selection 

 exercised by insects. It is one thing to admit 

 that the colour of its flowers is of direct utility to 

 a plant ; it is quite another to assert that the 

 colour in question owes its origin and develop- 

 ment to natural selection. Our attitude towards 

 the generally accepted explanation of the colours 

 of flowers is similar to that which we adopt 

 towards the theory of protective mimicry among 

 animals. In certain cases we are prepared to 

 admit that the mimicking organism derives benefit 

 from the likeness ; but this, we assert, is no proof 

 that natural selection has originated the likeness. 



The theory that flowers have developed their 

 colours in order to attract insects to them, and 

 thus secure cross-fertilisation, is based on the 



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