462 KINSHIP AND ADAPTATION 



plants in their responses to outside influence arc sometimes 

 capable of acting in one way rather than in another wa}' which 

 is equally possible, then all that is essential to what is here 

 meant by choice will be conceded, and he may be willing to 

 entertain an liypothesis which squares well with what we 

 know of all living things. In such u hj-pothetical view we 

 need not suppose that every action oi every creature is an 

 act of will. Many of our own acts are, as we say, mechanical 

 or habitual. We may well suppose that most of the behavior 

 of lower organisms, including the behavior' of growth, is of 

 this sort. Nor do we need to suppose that consciousness 

 more than ver}^ remotelj' like our own accompanies any of 

 the actions or reactions of plants. All the hypothesis requires 

 is that sometimes, even with dimmest consciousness, any 

 organism maj' be free to choose at a critical moment between 

 alternatives jDrofoundly affecting its constitution. 



By way of example let us suppose the seeds of a primitive 

 buttercup to be carried near the seashore and to begin to 

 sprout. Such plants are not accustomed to so nmch salt as 

 would then be in contact with their roots. Here is a change 

 of condition, favorable, as we have seen, to the occurrence 

 of mutations. It has lieen found by experiment that plants 

 of the same kind placed under the same conditions will absorb 

 different amounts of the same sub.stance, as, for instance, 

 common salt. Thus of several seedlings the same in kind 

 and age, growing with their roots in the same salt solution, 

 some will absorb a larger percentage of the salt than others, 

 and, indeed, may lie poisoned while others survive. Some- 

 times even the same individual may respond tlifferently at 

 different times. Now, what we ma)' suppose to happen, 

 according to our hypothesis, in the case of the buttercup 

 seedhngs is that some of them might choose t(.) keep out so 

 much of the salt that tliey could not get water enough to 

 hve; others might let in so much salt as to be poisoned by it: 

 while still others might let in just enough salt to permit their 

 having sufficient wat(>r, but not so much salt as would kill 

 them. The sui'vivors, as a consequence of their choice, 

 would liave their sap saltish and thus every organ woukl l)e 

 affected in an unwonted way. Their seeds would start with 



