INTRODUCTION TO BIRDS. 261 



what has happened. These are a few more of the ways in 

 which birds bear out the biologist's assumption that they 

 are closely related to man. White-rumped shrikes, blue 

 jays, house wrens, and English sparrows will reveal these 

 traits ; and if you will study the birds in your own neigh- 

 borhood, you may be able to discover additional traits. 



Be continually on the alert. If you hear a bird call, 

 catch a glimpse of the bird; it may be that you will have 

 to run; or, if it is an insectivorous bird or a seed-eater, 

 you may have to steal around the base of the tree several 

 times, tracing the bird's fleeting shadow as it creeps in and 

 out among the leafy twigs. It is making as little noise 

 as possible, so that it may not frighten the worm out of 

 sight, and you must do the same with respect to the 

 bird; 



