Evolution theory put to the test
New findings have repeatedly given rise to revising the theoretical foundations of evolutionary biology. Now some researchers are calling for the tried-and-tested construct of thought to be expanded again - rightly so?
Charles Darwin (1809-1882) hesitated for many years before publishing his theory of evolution. He was aware that the theory, as simple as its basic principles seemed, could not readily explain a number of biological phenomena. He would have hesitated even longer had he not learned in the 1850s that the British naturalist Alfred Russel Wallace (1823-1913) was developing ideas similar to his own. Darwin had been working on the theory for 20 years at the time and feared Wallace could forestall him with a publication.
In a preliminary publication, both naturalists had the basics of their concept read out to the Linnean Society of London in 1858, but initially met with little response. Darwin's theory of evolution first became known to a wide audience with the book "On the Origin of Species by Means of Natural Selection", which was published the following year. Contrary to what the title suggests, the core of the work is not the question of how new species develop, but the mechanism of natural selection. In the introduction, Darwin summarizes its cornerstones in two sentences, reproduced here in German translation:
"As many more individuals of each species are born than can possibly survive, and as there is thus a frequently recurring struggle for existence, it follows that every being, if changed even slightly in any way, which is advantageous in the complex and sometimes changing conditions of life, has a better chance of survival and is thus naturally selected. Due to the strong principle of inheritance, any strain selected will tend to propagate its new and modified form."
Here is everything you need to know about the basic principles of natural selection. Adaptation to the environment follows from the combination of excess offspring, struggle for existence, variation, heredity and basic ecological conditions. These relationships can be reproduced experimentally as often as desired and represent a secure law. In this respect, it is actually no longer a theory, which is why we usually speak of evolutionary biology instead of evolutionary theory.
Some scientists are now calling for the theoretical foundations of evolutionary biology to be revised in order to create what is called an extended evolutionary synthesis…