He was reviled as a monkey. The natural scientist Charles Darwin was aware that his new theory would offend many people. 150 years ago, his controversial second major work was published.
He was the revolutionary who pushed man from the throne of creation. Charles Darwin (1809-1882), an Anglican theologian by training and almost a country parson, brought down the pillars of biblical belief in creation. Since Darwin, man must be seen as an animal – albeit in a special position. On this Wednesday 150 years ago, on 24. February 1871, his second major work was published: "The Descent of Man and Sexual Selection".
Already in his 1859 work on the "Origin of Species" Darwin had refuted the idea that God had created all species at once and unchangeably. For five years, from 1831 to 1836, he had traveled the world on the research ship Beagle, analyzing animals and plants and recognizing the mechanisms of evolution.
In his theory, the natural scientist describes variation and selection as fundamental principles of life: In the struggle for food and habitat, only those who are best adapted to their environment can survive – which is by no means always the case for the biggest and strongest.
This selection leads over generations to a change of the types. A drumbeat that also led to a bitter debate about the authority of the Bible – a dispute that still persists today in the U.S. between creationists and natural scientists and in the conflict over biology education.
Not the crown of creation, but part of nature
In his first work, Darwin shied away from applying this doctrine to man – knowing full well how much opposition he would provoke. In "The Origin of Species," he merely hinted that he also did not see man as the crown of creation, but as part of nature. Only twelve years later Darwin dared to set forth this insight in a two-volume work.
This work deals above all with what distinguishes man from the animal and where similarities exist. Darwin expresses in the first section the amption that humans had developed in Africa. He states that his intellectual and moral abilities developed over a long period of time – not at the act of creation in paradise.
The Briton also opposes the idea that human races are different species. In the second part, Darwin describes the mechanism of sexual selection – first on the basis of insects, fish, amphibians, birds and mammals. The third part then deals with the effect of sexual selection on human development.
"The difference between humans and animals is only gradual, not fundamental," he writes. Nevertheless, humans do not lose their special position in nature. For Darwin, humans are "the most dominant animal that has ever appeared on earth". For he has heightened mental faculties, verbal language and moral ability.
Environment essentially shaped by preferences of females
According to the Tubingen Darwin expert Eve-Marie Engels, this also means that if the conditions of life change, man does not have to grow a thick skin, no claws, no fangs. Intellectual abilities, cultural habits and techniques allow him to adapt to nature.
Moral sense and religious ideas are also products of evolution, according to Darwin. Only human beings are capable of orienting their actions to moral principles and norms. "It is the noblest of all qualities in man that leads him, without a moment's hesitation, to sacrifice his life for that of a fellow creature," writes Darwin.
With regard to sexual selection, the natural scientist emphasizes that humans and animals have characteristics that are important in the search for a mate, but have no discernible value for survival, and may even be more of a hindrance to it: This is true, for example, of huge deer antlers as well as striking peacock feathers or human ideals of beauty. Darwin calls the two evolutionary forces the "male competition" and the "female choice". He concludes that the environment is essentially shaped by the preferences of females. For they are the ones who choose their mates wisely.