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Spencer Heath's

Series

Spencer Heath Archive

Item 2174

Two typed ring-binder pages with penciled editing, numbered in pencil pages 9 and 10, fragment of a longer piece of writing on population.

1930s?

 

 

 . . subsistence and able also to utilize a wider range of materials for food and live longer lives. Numbers now advance, not by greater reproductivity but by extending the duration of life; not by higher frequency of birth but by less frequency of death.

 

     When, relative to the increasing numbers, subsistence again declines this necessarily shortens the lives and tends to shorten the numbers. But this damming up of the stream seems to cause the number of units and its vol­ume to increase. That which causes the existing numbers to live shorter lives seems to stimulate reproductivity and com­pel the flow of life to manifest itself in more numerous units by way of compensation for the shortening of their span. The increase in numbers that results from the shortened span accompanied by a heightened reproductivity provides a broader numerical base upon which mutations and variations may occur and this vastly increases the probability of favorable modifications tak­ing place and creatures of superior form, habits and capacities for adjustment to environment being brought forth.

 

     This process is to be observed generally and not alone with respect to decline in subsistence relative to need but also under secondary and less fundamental influences that would other­wise diminish the population by shortening the average duration of its individual lives.

 

     Nutrition, however, being at the basis of all biological growth and organization and upon which all maintenance depends, a deficiency in this respect may be taken as the fundamental negative influence among all those which tend to the disintegration of biolog­ical organisms. This is strikingly illustrated in the re­productive behavior of the unicellular forms of life that maintain an indefinite continuity through the process of bod­ily division.

 

     This monad form of life receives its nourishment from its environing fluids only through its outer envelope or cell walls the surface of which must be sufficient to maintain the body within and enable it to grow. But since in the course of enlargement the surface can increase at only one half of the rate at which the increase of volume or mass must take place a critical state is bound to arise in which there is a fine and precarious balance between the needs of the organism and its capacity to absorb the necessary food to meet them. At this juncture some form of disintegration must take place. The characteristic expedient of the living cell is to divide itself into two daughter cells each of which has only half the mass and therefore substantially twice the relative amount of surface for absorbing food.

 

     Thus at the base of all higher life, the single cell, it is clear that multiplica­tion of numbers does not proceed from any increasing abundance of the food that can be obtained but rather the reverse; it is in fact a necessary technique drastically enforced upon the organism by its inability to obtain sufficient food. The necessary disintegration takes the form of division of structure with­out division or disintegration of function and in this way the vital continuity is assured and achieved. In this view nutrition is clearly seen to be not a positive factor as commonly supposed but a negative factor in the process of reproduction, and that, in the simpler forms of life at least, increase in numbers in the face of insufficient nutrition is the only form in which the continuity can be maintained.

Metadata

Title Subject - 2174
Collection Name Spencer Heath Archive
Series Subject
Box number 14:2037-2180
Document number 2174
Date / Year 1930?
Authors / Creators / Correspondents
Description Two typed ring-binder pages with penciled editing, numbered in pencil pages 9 and 10, fragment of a longer piece of writing on population.
Keywords Biology Population