234 NATURE STUDY. 



The Struggle for Existence. 



BY EDWARD J. BURNHAM. 



A quotation from Professor Chapman, on another page 

 of this number of Nature Study, with reference to the 

 increase of bluebirds since the great destruction caused 

 by the " freeze " in the South a few years ago, suggests 

 anew the thought of the terrific struggle for existence 

 which, under normal conditions, goes on throughout all 

 nature. There is, indeed, no plant or animal, however 

 slow the rate of increase may be, which would not in time 

 over-run the entire earth if not restrained by barriers 

 which it cannot pass and checks from which it cannot es- 

 cape. 



The bluebirds suffered so severely in the South in the 

 winter of 1895 — probably more from lack of food caused 

 by sleet and ice than from actual cold — that they were ex- 

 tremely rare for several seasons, but now, after eight years, 

 they are apparently as abundant as ever. This fact indi- 

 cates that the bluebird is less restricted by enemies than 

 by want of food. When few in number, food is sufficient 

 and it increases rapidly, but the time inevitably comes 

 when the limit has been reached, and from that time on 

 there must be a constant search for food and an increasing 

 struggle, not with other birds and animals, but among 

 themselves — a struggle which means starvation for those 

 not strong enough to survive. 



This struggle for existence, with its attendant destruc- 

 tion of life, is the most pathetic thing in nature. We may 

 not hope to understand it, or to see how it can accord 

 with our ideas of mercy and compassion. We only know 

 that it is a fact, and that by means of it, through long ages, 

 have come the strength of wing, the fleetness of foot, the 

 sharpness of eye, the beauty of color and song among the 

 creatures of the woods and fields, the earth and air. 



