dries; and that's that. Those more favorably situated begin to dig in. Some 

 act faster than others. The faster ones get the water and send their shoots up 

 before the slower ones get a firm grip on the soil. And as the earlier ones 

 keep on growing and absorbing, the lead becomes greater and greater. The 

 struggle for limited quantities of minerals is similar. And the parts that are 

 aboveground, which soon turn green, have to grow fast enough to catch the 

 sunshine before they are outgrown and shaded by other indn'iduals. 



We have already seen that where many different species are present in an 

 area, their specializations usually make possible a larger total population than 

 a single species could maintain. Because species differ in height, in spread of 

 leaves, in depth of roots, in rate of absorption, and so on, several different 

 species fill the area more nearly completely. Nevertheless even different 

 species may compete for the things that they all need, especially water, min- 

 erals, and a place in the sun. The competition among the plants is, at any 

 rate, real, even if the struggle does not involve violence. 



Pure Chance Each individual seed or plant has a very narrow range of 

 action, and no ability to make decisions or choices. Accordingly, mere chance 

 plays a large role in the lives of plants. The inherited capacities of this tiny 

 sleeping baby plant inside a seed have no relation to where it will alight — 

 whether upon a dry surface or on a moist one, on a bit of fertile soil or on a 

 barren spot. If it never gets to first base, there can be no reproach. Nobody 

 can say that it lacks any of the virtues which are proper to members of its 

 species. It simply had no chance at all. Seeds that get a start and send their 

 roots down may be stopped by a flock of birds or insects, which destroy every 

 scrap of organic matter big enough to grab. These animals destroy the "good" 

 individuals along with the "bad" ones^ — as would a flood or a fire or a complete 

 drought. We can see why it is that of the thousands and thousands of in- 

 dividual seeds which a mature plant produces, only a very few will in turn 

 reach maturity and reproduce themselves. 



How great the role mere chance can play is suggested by comparing the 

 survival rates among human beings. Out of a thousand babies born, some 

 will die almost immediately because of defective organs or functions — breath- 

 ing, digestion, circulation, temperature adjustment, or whatever. In the 

 course of the first year others will die for various reasons — failure of the organ- 

 ism at some point to meet the conditions of nutrition or excretion or infection 

 or changing temperature. But the number of such failures is probably small. 

 For among different peoples, or among different sections of the same popula- 

 tion, the infant death rate varies from about 30 to about 300 per thousand 

 (see illustration, p. 545). 



This great variation has been used to argue that some stocks are "inferior" 

 to others. But if we accept this, we must account for the further fact that 

 in the course of time the rates decline more for the "inferior" stocks than for 



543 



