BRAIN v. MUSCLE IN NATURE
NO observer of animals can fail to have noticed how they seem to lack brain-power. Judged by human standards, a bird or beast is but a stupid creature. If, however,.we measure the other organs of animals by a similar standard, we shall not find them wanting. The adaptation of nearly every species to its environment compels our admiration. Some are wonderful athletes, others are possessed of marvellous strength, others exhibit incredible powers of endurance; in short, there is no physical characteristic in which some animal is not pre-eminent. There exist dozens of animals that are physically superior to man. But, notwithstanding this superiority, they are all his slaves, for mentally he is head and shoulders above them. Muscle is no match for mind.
Why is it that, of all the millions of animals, only one species -: Homo sapiens -: has "gone in for" brain development on a large scale ?
Other things being equal, it is obvious that the animal with the largest brain has the best chance of survival in the struggle for existence. As compared with brain power all other qualities are of minor importance. If the legs of one antelope are half an inch longer than those of another, the former has certainly, other things being equal, an advantage in the struggle for existence. But other things are so rarely equal. A slight advantage, such as this, may be easily counterbalanced by luck.
Two antelopes may be feeding together, when they are seen by a beast of prey. They fly together, and the faster one soon begins to lead, but he happens to stumble into a quagmire; his neighbour profits by his mistake and takes another course, so that the poor creature who is floundering in the soft mud is fallen upon and devoured by the pursuer, while its less speedy companion escapes.
On the other hand, it is easy to see how a little extra brain-power can assist a species. A cute antelope may not be particularly fleet, nor very strong, but he will be careful to choose as feeding grounds places where he cannot be surprised, and, when he is chased, he will follow the course best adapted to his mode of progression ; carefully avoiding all soft ground, he will profit to the uttermost by his knowledge of the locality; he will run, as far as possible, in a straight line, so that his pursuer will not be able to cut off corners.
Hundreds of athletic species, which are known to us only as fossils, might to-day be living, if, when the struggle for existence began to press hardly upon them, they had had the wit to build boats and sail away to some corner of the earth where the competition was a little less keen. Every organ of every animal is subject to variation, and the brain forms no exception.
How is it, then, seeing the enormous advantage in the struggle for existence which the possessor of a large brain enjoys, that natural selection has not developed more clever animals with large brains ? How is it that all existing species are not as cunning as the proverbial serpent? Why is the average animal so lacking in intellect ?
It is hardly necessary for me to adduce proof of this deficiency of brain-power among animals. Even Mark Twain noticed it; that humorist does not think much of the wit of an ant!
A pair of swifts once selected as the site for their nest the gateway of one of the colleges at Oxford. This was against regulations. So the college porter removed the nest.
The birds immediately began to build another on the identical site. This was also ruthlessly destroyed. The birds, with greater perseverance than intelligence, tried to construct a third nest in the same place. This was not obstinacy on the part of the swifts. They were unable to put two and two together; their brain-power was insufficient to enable them to understand that man objected to their nest being built on that particular site.
A dog is supposed to be an intelligent animal, but it will run away from a stuffed bear. An elephant, who is the wise man among animals, will actually pick up its own goad and hand it to the mahout!
But why multiply instances showing the limited brain-power of animals ? Dozens of examples will occur to every one of my readers. It must not be thought that I assert that natural selection does not produce brain development among animals. It does. The crow is, in this respect, an enormous advance on the oyster. What I maintain is that, seeing the importance of the brain, we might have expected that this would have been developed in animals in preference to the other organs of the body. Yet it is the physical rather than the mental parts of animals which have been developed. Can we explain this phenomenon ?
Herbert Spencer attributes the great development of the brain of man to the fact that he possesses a hand -: an organ whereby he is able to appreciate space in three dimensions, and to understand the nature of solids. Every animal, which is not gifted with a grasping organ, possesses but a small degree of intelligence. This assertion, however, even if true, does not explain much. For we naturally ask, Why have not all creatures developed grasping organs ?
It seems to me that the secret of the lack of brain power of animals lies in the fact that the brain is an organ which takes long to reach maturity, and which, in the early stages of development, is not of great use to its possessor. It is scarcely necessary to adduce proof of these two assertions. It is a matter of common observation that, long after a man begins to decay physically, his brain continues to develop. While we may take half a dozen new-born babes, who are potentially the cleverest men in the world, and set these upon an uninhabited island and they will surely die, in spite of their large brains. Dame Nature takes into account only the present value of an organ. She selects those animals which are, for the time being, best able to take care of themselves, best adapted to their environment. She pays no attention to potentialities.
If any one were kind enough to leave me a legacy of £1000 -: a most unlikely contingency -: I should be deeply grateful, and think all manner of good things about that person; but if any one, in recognition of my services to mankind, were to leave to me, or my family, £1,000,000, payable one million years hence, I should not say as much as " Thank you." The present value of a cheque for £1,000,000 dated January 1st, 1,001,906, is nil. So is the present value of a baby's brain.
A tiger will not refrain from eating up a spotted deer because the latter, if spared, will develop into the cleverest spotted deer that ever gambolled in the jungle. Natural selection acts upon young and old alike ; but it is the young developing creatures upon which Nature comes down with so heavy a hand ; probably not one in a thousand of these reach maturity, upon an average. It is obvious that a most brilliant young animal may easily prove no match for the "old hand" of only mediocre ability. Hence the shortness of the period of helplessness is the feature most conducive to the preser¬vation of a species -: not necessarily a short period of development, but a short period of helplessness. Hence, in the lower forms of animal life, the young hatch out as larvae, able to take care of themselves in the struggle for existence, or, if helpless, are protectively coloured to a marvellous degree. So long as Nature is hampered in this manner, so long as she is obliged to manufacture animals at express speed, she has no opportunity of giving her creatures a large brain, which takes time to make.
Millions of organisms which, properly speaking, have no brains, make a very fair fight in the universal struggle. A large brain, however, will greatly assist a species the moment it is fully developed. It is, therefore, obvious that, if Dame Nature can only hit upon some device whereby the young of a species are protected until they are practically full-grown, she will be able to develop in them large brains, and then that species will do wonders.
Nature has solved the problem. The solution is the evolution of mothers. It is obvious that if the full-grown members of the species can be made to protect and fight for the young ones, their development need not be rushed, they need not, so to speak, be hastily put together; time and care may be lavished in the making of them.
Hence the origin of the maternal instinct. The greater the protection given by the parents to the young, the greater the time that can be devoted to the develop¬ment of the animal. It may be asked, if this was all that Nature needed -: the evolution of mothers -: how is it that, since this has occurred, all the higher animals are not as clever as man, or nearly as clever? The answer is that the maternal instinct, while favourable on the whole to the species, may be fatal to the individual; and if all the individuals perish, what is to happen to the species ?
Animals with young are at a disadvantage in the struggle for existence. It probably has happened that many races of animals have perished owing to the excessive development of this instinct. The parents would not save themselves by deserting their offspring; consequently the whole family perished. Among most species the protection to the young afforded by the parents is so inadequate that, of the young ones, it is the physically strong, rather than the mentally powerful, that tend to survive.
One animal, however -: Homo insapiens -: in which the maternal instinct was highly developed, learned to take shelter in caves and to barricade the entrance to his shelter, so that the females were able to bring up their young without fear of molestation. There was then no need for the development of these to be hurried. The weakest of the family perished from disease and hunger while still under their mother's care, but the healthy children emerged, some years after birth, equipped with a large brain, so that they were able to overcome the superior strength of the other animals by craft, and the most crafty of insipient mankind survived and left offspring.
Thus Homo sapiens appeared upon the scene. He is the animal which pinned its faith to the brain, and his faith has not been misplaced. He has sacrificed everything to the brain. Almost all his other organs -: his legs, arms, eyes, teeth -: have been allowed to degenerate, but his brain has been kept up to the highest possible efficiency. He now reigns supreme over all the animals, which, so to speak, put their money on muscle, on brute force. These backed the wrong horse, and therefore are now the servants of those who staked their all on the brain.