THE INSTINCT OF THE COWBIRD 



question, " Why the victimized birds rear the 

 parasite? " was answered to my belief in this 

 way: I believe that the yellowbirds had had 

 experience with cowbirds before, and intelli- 

 gently understood that they must sacrifice 

 their first brood in order to raise a second 

 brood unmolested. The actions of the birds 

 when they discovered the parasite egg, their 

 great distress, their consultation and prompt 

 action, their neglect to lay the usual number 

 of eggs can be construed in no other light. It 

 is far beyond the province of instinct. 



My second question, " Why the young cow- 

 bird deserts its foster-parents? " is already in- 

 telligently answered. It is no desertion. The 

 foster parents turn over the parasite to its own 

 mother, in a matter-of-fact way, and then go 

 about their own affairs in peace. 



My third question, " Why do young cow- 

 birds lay eggs in other birds' nests instead 

 of building nests for themselves? " 



When the cowbird was out of the shell, it 

 was big and black. It was my first young 

 cowbird, and I thought it was a male. I 

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