THE FLOWER AND THE BEE 



Many colors are better than one, since the flowers are rendered 

 more conspicuous by contrasts with each other as well as with 

 foliage, and insects are less liable to visit them indiscriminately. 

 The various floral colors have been evolved by the selective 

 agency of insects, especially bees, which are able easily to dis- 

 tinguish between them, and in the absence of visitors flowers 

 would have remained green, or dull-colored, similar to wind- 

 pollinated blossoms. In some instances Mueller believed that 

 the visitors manifested a preference for certain colors, as honey- 

 bees for blue, butterflies and humming-birds for red, hover- 

 flies for yellow, and carrion-flies for lurid purple; but in the 

 light of more recent investigations it may be doubted whether 

 insects receive more pleasure from one color than another. 

 The usefulness of floral-color contrasts is sufficient to explain 

 their development without recourse to the supposition that they 

 afford an aesthetic pleasure to insects. 



With the exceptions of the criticisms of Bonnier, in 1879, 

 Mueller's doctrine remained almost universally unquestioned 

 until 1895, when Felix Plateau, of the University of Ghent, 

 made the sensational assertion that Mueller had been misled 

 by a too vivid imagination, and that in the mutual relations of 

 insects and flowers the bright colors of the floral leaves have 

 not the important role that he had attributed to them. All 

 the flowers in nature might be as green as their leaves, without 

 their pollination being compromised. It is not their sense of 

 color but their sense of smell which enables insects to discover 

 flowers which contain nectar and pollen. 



Assertions so revolutionary were naturally received with 

 much incredulity, and in some instances, as Plateau naively 

 remarks, were criticised with merciless severity. While reply- 

 ing to his critics with admirable courtesy. Plateau constantly 

 sought for new evidence, and actively maintained his views 



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