The Making of Species 



10. The case of certain diurnal moths mimick- 

 ing butterflies appears to be explicable without 

 the aid of the theory of protective mimicry. 

 When two species adopt the same method of 

 obtaining food, it not infrequently happens that 

 a professional likeness springs up between them. 

 Of this the swifts and swallows afford a striking 

 illustration. 



11. As a set-off to the cases where the alleged 

 mimicry is confined to certain seasons of the year, 

 we may cite the case of the pheasant-tailed 

 Jagana (Hydropkasianus chirurgus), which in its 

 winter plumage might easily be mistaken, when 

 on the wing, for the paddy bird or Pond Heron 

 (Ardeola grayii\ both being of like size and 

 having a brown back, long green legs, and white 

 wings. Moreover, they are to be found in 

 the same localities in India. At the breeding 

 season, however, they are absolutely different 

 in plumage. 



Yet another argument commonly adduced in 

 favour of the theory of protective mimicry is that 

 local variations of the imitated species are some- 

 times followed by the imitator ; thus the butterfly 

 Danais chrysippus shows a white patch on the 

 hind wings in Africa, and this is followed by 

 its mimic. 



But the same thing occurs, quite irrationally, 

 so to speak, among birds. The peregrine falcon 

 and hobby of Europe are only winter migrants 



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