A momentous discovery
Growth and decay, passing things on and renewal: evolution is life, and life is constant change – from the single-celled LUCA (last universal common ancestor) 3.6 billion years ago up to the new climate challenges today, for example. The word ‘evolution’ is also used to describe gradual changes in culture and society. Over the coming six months, this dossier produced by the Communications Department will be devoted to one of the most momentous discoveries ever: evolution.
“I feel as if I’m confessing a murder,” wrote Charles Darwin in his book “On the Origin of Species”, published in 1859. He was evidently aware that his new insights at that time were not only presenting some scientific theory. No, the British naturalist was shaking the prevailing conception of the world. Why? Because he was providing an explanation for the gradual development of life, which constantly adapts to new environmental conditions – in other words, does not stem from a unique act of divine creation. “Evolution as a gradual development,” says Prof. Joachim Kurtz from the Münster Graduate School of Evolution, “is the most widespread scientific concept for understanding processes – everything from the origins of the Earth to human societies.” Evolution, he says, is a scientific fact which is based on empirical measurements and observations, and which is explained by the theory of evolution.
This is something that even the Catholic Church had to recognise – but that took precisely 137 years. It was only in 1996 that Pope John Paul II declared that the theory of evolution was “more than a hypothesis”. Nevertheless, in 2005 US President George W. Bush demanded equal time in schools for teaching “intelligent design” alongside the theory of evolution. “Intelligent design” is the belief held by evangelical Christians that the origins of life go back to a creative intelligence. One more reason why Darwin Day – celebrated since 1995 on Darwin’s birthday, 12 February 1809 – also represents a stance taken against scepticism towards science.
“The gradual developments,” explains Prof. Jürgen Gadau from the Institute of Evolution and Biodiversity, “are the result of selection which, from among hereditary variations, chooses those which have adapted best. As a result, the hereditary features of a population or other organic structures gradually change.” According to the German Duden dictionary, a continuous step-by-step development can also refer to the “evolution of forms of society”; as far as the cultural evolution of humans is concerned, it relates to behaviours learned being passed on to the next generation.
Many people associate evolution with the phrase “survival of the fittest”. Darwin used the phrase to describe his idea of natural selection, according to which it is those individuals that are best adapted to the environment – not the strongest – that will survive. Successful adaptation can also exist in a division of labour – in colonies of bees and ants as much as in human communities. In other words, social Darwinism is not necessarily the method of choice. Cooperation also exists between different species. For example, fungi and cyanobacteria combine to form lichens, a new organism. Many species of plants depend on insects for reproduction and reward them with nutritious nectar.
Another surprising finding is that diseases can be an advantage in the selection process. The hereditary disease sickle-cell anaemia provides protection against malaria and, in regions in which the disease is widespread, around a third of the population have this hereditary trait. But there is more: “Paradoxically, evolution can not only eliminate diseases but also strengthen them, for example through rapidly changing pathogens,” says Prof. Ulrich Dobrindt from the EvoPAD Research Training Group (Evolutionary Processes in Adaptation and Disease).
The model of cultural evolution can make a contribution to research into human universals. Some years ago, an interdisciplinary team of researchers in the United States investigated the universality of music. All over the world, people sing and dance; tonality and rhythm are can be found everywhere. Music is used mostly in connection with bringing up children, religion, healing processes, dancing and love.
Although Darwin used the word “murder” as a metaphor, it is still true that mass extinctions in the past have always produced new species every time – such as the dinosaurs around 250 million years ago. Today, the man-made climate crisis requires an adaptation to environmental conditions changing faster than ever before, thus presenting evolution with an enormous new challenge.
Author: Anke Poppen
This article is from the university newspaper wissen|leben No. 1, 31 January 2024.