As ground dwellers, our ancestors were easy victims of the great predators, who hunted them down by day and night. Until they started use tools, they were totally dependent of destiny. Naked bodies and empty hands did not protect anything against wild beasts. Bad weather, starving and deseases killed a big part of these defenseless pre-humans.

 
PART I: EVOLUTION OF THE HUMAN MIND
Many edible nuts are too hard for even a caveman to crack between his teeth. Accordingly, they were useless to early man until some genius of his day discovered that any nut could be opened if it were placed upon one stone and struck hard with another. Better fed, the family of this innovator proliferated.

A man sat cracking nuts between two stones, one stone broke and the broken edge cut his hand. Since the edge had cut through his skin and drawn blood, it might also cut through the skin of the small animals he caught, making it easier to get at the meat. The first knife was invented! He and those close to him, and those intelligent enough to imitate them, increased in number. They had a cutting tool which made it possible for them to skin and eat meat in less time, so they had more time for hunting.

Later, someone may have come upon a long straight stick, splintered at one end. He used his stoneknife to sharpen it still more at the end. His dawning intelligence told him his pointed stick might be a better weaponagainst big cats than the clubs which he and the other men carried. From that time he, his sons and their sons carried impaling sticks whenever big predatorswere near. Foresight, genetically transmitted to their descendants, had given them a new weapon which they used with devastating effect against their natural enemies.

There is scarcely any doubt that the development of brain power, of intelligence, was the decisive force in the evolutionary process which culminated in the appearance of the species to which we belong. Natural selection has brought about the evolutionary trends towards increasing brain power because brain power confers enormous adaptive advantages on its possessors. It is obviously brain power, not body power, which makes man by far the most successful biological species which living matter has produced.
 
 
PART II: TECHNICAL AND SOCIAL THREATS AGAINST EVOLUTION

2.1 AGRICULTURE AND INDUSTRY
One of the greatest helps to the survival of the less intelligent was the development of farming. This is not to say that those with superior mental equipment did not farm. They did better than the others as a rule. But farming, much more than hunting, enables parents to rear and protect their less capable children until they reach the age of reproduction. In a state of nature, many of these would have been picked off early by predators or have been the victims of infanticide or starvation. In farming even simple-minded people can subsist and increase their kind. They might not be bright enough to add or subtract, but they could multiply as never before.

Yet even the agricultural revolution was subsequently surpassed, as an incubator and supporter of the less bright, by the industrial revolution. It doesn't take a great deal of creative thinking to hold a routine job in a factory. Here a limited mind can be an asset, since it permits mastering a dull, repetitive task which would bore a good mind to distraction.

 
2.2 WELFARE
Today, in civilized countries, so all-embracing is the protective web of health services, unemployment benefits and womb-to-tomb welfare that millions grow up and breed despite weaknesses and deficiencies that would have decimated them 20.000 years ago.

With savages, the weak in body or mind are soon eliminated; and those that survive commonly exhibit a vigorous state of health. We civilized men, on the other hand, do our utmost to check the process of elimination; we build asylums and care-centers and our medical men exert their utmost skill to save the life of anyone to the last moment... Hermann J. Muller was the first geneticist to win a Nobel Prize. His voice is certainty one to respect. He has warned, "We probably save for reproduction, by means of our advanced medical, industrial and social techniques, more than one-half of the people who in past times would have had their lines of descent extinguished as a result of their genetic shortcomings."

 
2.3 COMFORT AND INACTIVITY
Comfort corrupts. Man of today is represented by stressed people with cell phone, playing and chatting and goofing on social networks. Like the body develops muscles when training, the brain at creative thinking develops connections between neurons. Human brain is today stimulated to solve problems, supported by digital systems and is being trained for operating computerized systems with accuracy and high speed. But, what kind of intelligence is developed when we use our capacity to connect to huge systems, where we just are a little part? If something struggles in the system, we stop and wait for solution by third part.
If the Cro Magnon man had behaved the same way, accepted to walk completely disarmed, without knife or spear and accepted to save the few belongings he had, tools, skins and possible food supply, in the hand of an alien, he should not even been discussed here as we not should have been born.
 
 
PART III: POLITICAL THREATS AGAINST EVOLUTION
Toady, a mayor part of the population is what might be described as dull. When the underachieving masses multiply sufficiently to overwhelm the upper classes, they abandon the ancient policy of live and let live. In areas where the ratio of the masses to the elite is large and the established leadership is inadequate, a potentially explosive situation is created. If incendiary leaders appear and ignite this explosive atmosphere, the social detonation is devastating.

Amid the violence and confusion, the masses can be incited to turn upon the more intelligent members of their own people and either expel them, imprison them or slaughter them. This bloody process, known as class war, has great historical significance and has exerted a major evolutionary influence on man himself. An examination of the phenomenon is gruesome, but it is essential to an understanding of some of the worst aspects of the human condition.

The masses rampage, seize and steal the possessions of others. Violence is also inspired by the desire to destroy the galling evidence of their own relative inferiority. They are impelled to obliterate all those they feel are above them, whether the superiority lies in wealth, position, character, beauty or intellect. The only intelligent men spared are the masses' own radical leaders. But not for long. Soon most of them expire in the infighting that takes place as the revolutionaries battle each other for power.

 
3.1 CLASS WAR IN FRANCE
The French Revolution is the first great instance in modern history of what occurs in a nation when the revolutionary segment of the masses gains the upper hand. The French Revolution was an universal insurrection of the lower orders against the higher. "Liberty and Equality" was the universal cry of the revolutionary party. The shrieks of death were blended with the yell of the assassin and the laughter of buffoons.... The French Revolution was a small-scale preview of the horrendous class wars of our own time.

3.2 THE RUSSIAN REVOLUTION
The Russian intellectuals, or Intelligentsia, as they called themselves, had for generations been Russia's brain and conscience. In the Intelligentsia were concentrated Russia's best hopes of progress and civilization. The Intelligentsia stood bravely between despotic Czardom and benighted masses, striving to liberalize the one and to enlighten the other, accepting persecution and misunderstanding as part of its noble task... the Intelligentsia was not of one mind. It had its conservatives, its liberals, its radicals, even its violent extremists— from which the brains of Nihilism and Bolshevism were drawn.... The intelligentsia backed the political revolutions of 1905 and March, 1917. The latter, in particular, fired it with boundless hopes. The Intelligentsia believed that its labors and trials were at last to be rewarded; that Russia allied with satelite states in the name of the Soviet Union was to become the liberal, progressive nation of its dreams.

Then came the Bolshevik coup at the October revolution, 1917 when the extremist wing of the Intelligentsia accepted Bolshevism with delirium, but the majority rejected it with horror. The Bolsheviks had long hated and despised the intellectuals, regarding them as enemies to be swept ruthlessly from their path. The result was a persecution of the intellectuals as implacable as the persecution of the bourgeoisie. The Russian intellectuals were killed, starved, and driven into exile. Multitudes perished, while the survivors were utterly broken.

The initial practice of the Bolsheviks, carried out for many years after their revolution, was to persecute all classes except the property-less portion of the laboring class. This led to the flight abroad of millions of intelligent Russians . the remaining middle and upper classes were sent to slave labor camps "to die usefully." The salvation for the following administration of the Soviet Union was the remaining effects of the  caste system of Tsarist Russia wich had not permitted the intelligent to rise to any level for which they could qualify, as currently in France and the United States. Accordingly, there were more genes for intelligence buried in the Russian masses than in the masses of some other countries. These were the chief source of bright young people in Communist Russia.

The Soviet authorities were quick to grasp the significance of the scientific community to the nation and provided extensive funds or resumption of the basic research effort. The scientists again became an elite group. Unfortunately, however, they were not exclusive enough to escape the new purge that spread throughout Russia in 1929, and many prominent scholars were exiled or disappeared….When the purge subsided during the late 1930s, emphasis was again placed on practical research that could be applied to strengthening the military might, and this effort paid off in the later years of World War II.

Communism is based upon a fundamental biological phenomenon. It is able to exploit the rapid increase of people with mediocre intelligence, an increase which occurs because natural selection no longer keeps their numbers down. This is the source of inner confidence which gives Marxist revolutionaries the expectation of total world conquest. Communist leaders well know that their voluntary followers must be recruited from people who are mentally immature— people who, even though of adult age, have never really grown up.
Even when the failures of communism are fully and painfully evident to thinking persons, it will continue to make gains as the ratio of unthinking people increases. This is why Communists do not have to rely exclusively on war. They need only to wait until the intelligent are sufficiently outnumbered in countries not yet under Communist control.