Competition (biology)

“ No one will deny that there is, within each species, a certain amount of real competition for food--at least, at certain periods. But the question is, whether competition is carried on to the extent admitted by Darwin, or even by Wallace; and whether this competition has played, in the evolution of the animal kingdom, the part assigned to it. ”

“ Making these highly favourable assumptions, what follows:—The queen-ant lays eggs that give origin to individuals in each of which there is achieved an economy in nerve-substance of one-2000th of its weight; and the implication of the hypothesis is that such an economy will so advantage this ant-community that in the competition with other ant-communities it will conquer. For here let me recall the truth before insisted upon, that natural selection can operate only on those variations which appreciably benefit the stirp. ”

“ We can dimly see why the competition should be most severe between allied forms, which fill nearly the same place in the economy of nature; but probably in no one case could we precisely say why one species has been victorious over another in the great battle of life. ”

“ But granting the fact that variations may and do occur in all parts of the organism, it is clear that, in a group of organisms surrounded by enemies, those individuals which varied in the direction of swiftness, cunning, inconspicuousness, [AG] or resemblance to protected forms, would, other things being equal, stand a better chance of escaping elimination.
Elimination by competition is, as Darwin well points out, keenest between members of the same group and among individuals of the same species, or between different groups or different species which have, so to speak, similar aims in life. ”

“ So that we again are asking ourselves, To what extent does competition really exist within each animal species? Upon what is the assumption based? The same remark must be made concerning the indirect argument in favour of a severe competition and struggle for life within each species, which may be derived from the "extermination of transitional varieties," so often mentioned by Darwin. ”

“ For reasons obvious upon reflection, the competition is often, if not generally, most severe between nearly related species when they are in contact, so that one drives the other before it, as the Hanoverian the old English rat, the small Asiatic cockroach in Russia, its greater congener, etc. ”

“ After citing the rodents that combine to store food for the winter, or fall asleep about the time competition should set in; and the buffaloes which form immense herds to migrate across a continent to where food is plentiful; and beavers, which when they grow numerous, divide into two parties, and go, the old ones down the river, and the young ones up the river and avoid competition; after citing these and many others, he declares the mandate of nature to be: “Don’t compete!—competition is always injurious to the species, and you have plenty of resources to avoid it! ”

“ The idea which permeates Darwin's work is certainly one of real competition going on within each animal group for food, safety, and possibility of leaving an offspring. He often speaks of regions being stocked with animal life to their full capacity, and from that overstocking he infers the necessity of competition. But when we look in his work for real proofs of that competition, we must confess that we do not find them sufficiently convincing. ”

“ The effects of competition would, of course, have an extremely important effect upon any creature, in the same way as any other condition of nature under which it lived, must affect its sense of need and its opinions generally. The results of competition would be, as it were, the decisions of an arbiter settling the question whether such and such variation was really to the animal’s advantage or not—a matter on which the animal will, on the whole, have formed a pretty fair judgement for itself. ”

“ And in the same manner we find that, among all animal species, all the individuals of one and the same species compete with one another to obtain these indispensable means of life, or the conditions of existence in the wide sense of the word. They are equally indispensable to all, but really fall to the lot of only a few—“Many are called, but few are chosen.” The fact of the great competition is quite universal. You need only to cast a glance at human society, where this competition exists everywhere, and in all the different branches of human activity. ”

“ But the means of subsistence and other conditions of existence do not increase at the same [pg 142] rate; they are relatively constant. Thus competition must come about. Any organism that is, by fortuitous variation, more favourably equipped than its fellows maintains itself and reproduces itself ”

“ Elimination through enemies is more important, but has not much bearing on the question at present before us—the evolution of the conceptual. Elimination by competition, again, though a factor of yet greater importance in human evolution, has, nevertheless, so far as individuals are concerned, but little bearing on our present question. Few are eliminated through the absence of the conceptual faculty. ”

“ Competitive relations.—The assembling of plants and animals, with their prodigious possibilities of multiplication, brought competition, and with it a struggle for food which often became a struggle for existence, and out of this grew innumerable modifications of form and habit. ”

“ The result is that a competition is entered into between species and individuals within the species for place and for existence. This competition or struggle results in the dying out of the inferior, that is, of those who are not adapted to their environment. The gradual dying out of the inferior or unadapted through competition results in the survival of the superior or better adapted, and ultimately in the survival of the fittest or those most adapted. Thus the type is raised, and we have evolution through natural selection, that is, through the elimination of the unfit. ”

“ But this struggle is not to be understood in a crude and exclusive sense; there is a law of competition, but there is also—what is still more important—a law of mutual aid, and as soon as the scientist leaves his laboratory, and comes out into the open woods and meadows, he sees the importance of this law. Only those animals who are mutually helpful are really fitted to survive; it is not the strong, but the co-operative species that endure. ”

“ The seeds of one parent plant falling in a restricted area will be engaged in a competitive struggle for existence that is much more intense than many other parts of nature's warfare. In brief, the intensity of the competition will be directly proportional to the similarity of two organisms in constitution and situation, and to the consequent similarity of vital welfare. ”

“ In such cases what is described as competition may be no competition at all. One species succumbs, not because it is exterminated or starved out by the other species, but because it does not well accommodate itself to new conditions, which the other does. The term "struggle for life" is again used in its metaphorical sense, and may have no other. ”

“ Happily enough, competition is not the rule either in the animal world or in mankind. It is limited among animals to exceptional periods, and natural selection finds better fields for its activity. Better conditions are created by the elimination of competition by means of mutual aid and mutual Support. ”

“ From this may be deduced a second principle of competition, viz., the closeness of the competition between the individuals of different species varies directly with their similarity in vegetation or habitat form. This principle is of primary importance in the competition which arises between occupants and invaders in the different stages of succession. Those invading species that show the greatest resemblance to occupants in leaf, stem, and root form experience the greatest difficulty in establishing themselves. ”

“ Severe competition for the means of living, or the struggle for existence, is a necessary consequence of unlimited multiplication; while selection, or the preservation of favourable variations and the extinction of others, is a necessary consequence of severe competition. ”

“ There are degrees and kinds of life that are brought but little, or not at all, into competition. For example, between grass and the animals that feed upon it, there is practically no competition, for the more grass the more animals, and animals do not diminish the grass-growing area. ”

“ It is true that a blind, footless, degenerate animal could not cope with the active, keen-sighted, highly organized non-degenerate in free competition. But free competition is exactly what the degenerate animal has nothing to do with. ”

“ What he saw, and proved by an amazing wealth of illustrative facts, was that any variation in structure or character which gave to an organism ever so slight an advantage might determine whether or not it would survive amid the fierce competition around it, and whether {26} it would obtain a mate and produce offspring. ”

“ In the origin of new species by natural selection, the stress of competition determines the survival of favourable individual variations, and these, when by the continued operation of the process they have become constant, are added to those pre-existing characters of the species which are inherited from a remote past, and are witnesses of the operation of natural selection from age to age under ever-changing conditions of competition and variation. ”

“ Nor is there only thus a competition for subsistence, and arising thereout a gradual sharpening of all the bodily and mental powers which could aid in seeking or obtaining food; there is also in some cases a competition for mates, reaching occasionally the climax of elimination by battle. There is, indeed, competition for everything which can be an object of appetence to the brute intelligence; and, owing to the geometrical tendency in multiplication—the law of increase—the competition is keen and unceasing. ”

“ It is not generally realised how severe is the pressure and competition in Nature—not between different species, but between the immature population of one and the same species, precisely because they are of the same species and have exactly the same needs.... ”

“ The part or organ will thus retain its full size in the embryo, as we know to be the case with most rudiments. As soon as a part becomes useless, another principle, that of economy of growth, will come into play, as it would be an advantage to an organism exposed to severe competition to save the development of any useless part; and individuals having the part less developed will have a slight advantage over others. ”

“ When many of the inhabitants of a country have become modified and improved, we can understand, on the principle of competition, and on that of the many all-important relations of organism to organism, that any form which does not become in some degree modified and improved, will be liable to be exterminated. ”

“ From the lowest forms of animal life up to the highest, man, this law proves to be operative. It is not denied that there is competition for food, for life, within the species, human and other. But that competition is not usual ”

“ The legitimate inferences from animal behaviour are, that co-operation is in some cases a factor in the evolution of a successful species, that in human progress it has been an important factor giving strength to a creature weak in tooth and claw, and that this factor has co-existed, and still coexists, with that of competition, in the absence of which the race would be dragged down to lower levels of efficiency by the incubus of weaklings. ”

“ Under nature, the individuals of the same species are exposed to nearly uniform conditions, for they are rigorously kept to their proper places by a host of competing animals and plants; they have, also, long been habituated to their conditions of life; but it cannot be said that they are subject to quite uniform conditions, and they are liable to a certain amount of variation. The circumstances under which our domestic productions are reared are widely different: they are protected from competition ”

“ The question whether real competition ever exists is academic. Competition perhaps exists only rarely because seabirds partition resources through use of different feeding methods, selection of different-sized prey, and habitat zonation. ”

“ Competition, Specialization, and Organization [186]
Natural selection acts exclusively by the preservation and accumulation of variations, which are beneficial under the organic and inorganic conditions to which each creature is exposed at all periods of life. The ultimate result is that each creature tends to become more and more improved in relation to its conditions. This improvement inevitably leads to the gradual advancement of the organization of the greater number of living beings throughout the world. ”

“ Looked at in this way, multi­cel­lu­lar­ity presents itself as an escape from the rigour of natural selection, which for the unicellular organism had narrowed {19} competition to so desperate a struggle that any variation outside the straitest limits was fatal, for even though it might be favourable in one respect, it would, in so small a kingdom, involve a loss in another. The only way, therefore, for further advantageous elaboration to occur was by the enlargement of the competing unit. ”

“ For the enormous reproductive faculty of most organisms makes them multiply so rapidly as to press ever more and more closely against the limit of subsistence, and thus to produce competition for the means of living. ”

“ Can we suppose that any advantage, derived from new powers that prevent severe competition with kindred, can be permanently transmitted through succeeding generations to one small section of the species while there is free crossing equally distributed between all the families of the species? ”