Sunday, July 31, 2016

The Survival of the Marginal Part I

Consider Darwin’s Finches.  Which changed first?  Their bodies?  Or their behavior?  And why did they change their behavior?

The idea of the survival of the fittest is a mistaken understanding of the dynamics of evolution.  It is not those best adapted to an environment who win the game of life.  It is the weak, the losers in the competition for supremacy within their environment and within their species, who in the end triumph.  The fittest either come eventually to die, clutching the residues of their spoils, or survive on as prisoners, trapped inside the bounds of the field of their victory, hemmed in by the descendants of those they once drove forth into hardship.

For when the strong drive out the weak, what happens to the weak?  In their home environment, the weak may be well adapted, both physically and behaviorally, to exploit its resources, and prosper.  However, the weak must also compete against those like them, but stronger, both for those resources, and for the right to reproduce their kind.  But since they are the weak, they are outcompeted for food and reproductive rights by the strong. 

In a crowded environment, the strong  may physically drive them into the margins.  Even if the weak are not directly confronted by those stronger than they are, they may still be faced with starvation.  Certainly, they face an unpleasant choice.  They may choose to endure, and eventually die, perhaps without issue.  However, they may also choose to depart, and move out into the margins of their former environment.     

The margins will not be as favorable to the weak as was the center of the ecology that the strong still claim. The behaviors which served them in that environment will no longer be adequate, and different behaviors will be demanded. To survive, the weak will be forced to adapt. (And some will be prepared for this, because their old behaviors will have failed them, and they will be ready to change.) In particular and in general, a greater variety of behaviors will be demanded. Physically, they may be mal-adapted to their new environment, and their new behaviors must first compensate for this. Different food sources must be pursued. Different locations for food and even different varieties of food must be sought, because those sources they once relied upon will no longer be adequate, if they are available at all.  None of the sources which they once depended on will be available in sufficient quantity.

Meanwhile, their enemies may follow them.  They may be forced to deal with new predators, who may see them as a new opportunity for predation.  They may be forced to deal with new hazards. And their survival will depend on their ability to adapt their behavior in response.

In the old environment, the strong of the species are in a sense optimized, or will evolve to become so, both physically, and behaviorally.  And when they do become optimized,  the strongest will be the most fit to that environment, and any individual who deviates, the carrier of any other random mutation, will be inferior in its ability to compete, and thus selected against. As long as their environment remains constant, so will the species, and for these individuals, and their descendants, the process of evolution effectively ceases.  The only remaining outlet for change, a domain of random drift, within which the external pressures of selection are essentially absent, within which genetic alterations, which still randomly occur, in no way change the functional relationship of the species to its environment. 

Those driven into the margins, however, are not optimized to their new environment, either behaviorally, or physically. And because they are suboptimal, and suboptimal possibly to a variety of different optima, both physically and behaviorally, they may have choices.  Their new environment may present them with a selection of possible niches for them to move into, for them to both adapt to and mould to their behavior. (Every time a species successfully colonizes a new environment, it alters that environment, and thus the structure and relationships of the niches occupied by the other species already occupying that environment. and of course the species themselves.)

 First they must alter their behavior so that with their imperfectly adapted bodies they may best cope with their new reality. If they succeed and survive, and have issue, they pass these behaviors on to their descendants.  Physically, the descendants slowly evolve, as the shape of the new environment potentiates net forces upon them.   These provide relative advantage to the random mutations which create the altered structures that improve the ability of the species to cope and prosper, and relative disadvantage to those which do not.  (Note the earliest generations have the greatest opportunity to change behavior, and adopt to different niches.  Indeed, a random physical adaptation which is inappropriate to the behavior adopted by the parent may lead the descendant to alter its behavior, and thus branch into an alternate niche. This suggests that branchings, rather than predominately binary, would tend to be clustered about points of colonization, when the differing  opportunities reachable to the species are greatest in availability, number, and variety.)

The forces imposed upon the colonizing species would be of two basic types, push and pull, pressures and opportunities.  Singly, these would respectively tend to be dispersive and attractive.  However combinations of opportunities could be dispersive, and arrays of sources of pressures compressive.  As a result of these environmental forces, different combinations of vectors of radiation may result.

There is also the possibility that colonization happens into an environment where no particular niche offers sufficient opportunity for the new species to survive. No singular alteration of behaviors would enable survival, but a combination of  two or more groups of new techniques must be adopted if the species is, say, to acquire enough food to survive. The species may eventually come to physically adapt to one or another niche and specialize. It then may come to exploit that niche with sufficient efficiency to survive. Due to environmental forces, this may involve acquiring physical strength, over subsequent generations, and the weak become strong. 

However, it may also be that specialization is not possible, and the individual of the species must continue to exploit several niches in order to survive. Since physical adaptation to one niche will likely compromise its ability to exploit other niches, increase in the ability to exploit its environment might then be primarily a result of an increase in the varieties of behavior.  Behavioral adaptation, especially where an increase in the variety of behaviors is required, puts a premium on intelligence.  Of course, even the simplest act of colonization requires more intelligence than is needed by an optimally adapted species in its home environment.    

In the adaptation to its environment, a species acquires those qualities it needs, but in more than the quantities it needs.  The ability to meet the bare minimum of demands of the environment will not be sufficient.  Survival requires more than efficiency: In the distribution of coping abilities in its environment, the abilities of individuals in all but the lower tail of that distribution must exceed the demands of the environment.  This necessarily includes intelligence. 

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