Is Darwinism or Lamarckism true

Evolution theory : That's not true! Where Darwin was wrong

1. ACQUIRED CHARACTERISTICS

ARE INHERITED

Darwin's greatest faux pas was probably to believe in inheritance of acquired traits, as suggested by the French zoologist Jean-Baptiste de Lamarck. Darwin, of all people, was a Lamarckist! The two are often compared in school books to illustrate Darwin's innovation. In reality, however, it took over a lot from its predecessor. The problem: Darwin saw that there are always small differences between the individuals of a species, but he was not clear how they come about. As well as. Genes were not yet known, and certainly not mutations. After Darwin's death, it was more than 70 years before James Watson and Francis Crick deciphered the structure of DNA and ushered in the age of genetics.

In his need, Darwin therefore also appealed to external forces. For example, he thought that individuals who make greater use of certain organs have offspring in which those organs are more pronounced. So Lamarck's picture of a giraffe. It has a long neck because it always stretches towards the treetops. "Darwin invokes Lamarck again and again in his works, up to and including remarks that the village blacksmith has very muscular children and the village priest is rather pale, thin," says evolutionary biologist Ulrich Kutschera. Today one would no longer pass a biology exam with such assumptions.

2. THE TREE OF LIFE

Sometime in July 1837, Darwin picked up his red notepad, opened a new page and wrote, “I think.” Beneath it, he drew a diagram of a tree branching out in thin lines, the first representation of the “Tree of Life”. Many scientists now believe that the concept has taken off. Because it is based on the assumption that inheritance always only takes place vertically, that is, characteristics are passed on from parents to their children. But evolution isn't as neat as Darwin thought. We now know that genetic material is very often passed on horizontally, i.e. it is transferred from an individual of one species to an individual of another species.

In bacteria, this "lateral inheritance" has long been known and seems to be commonplace. Pathogens are particularly happy to exchange resistance genes, which is why there are more and more bacteria in hospitals that are resistant to numerous antibiotics. But also in higher animals one can find genes that were taken up by other species in the genome. Scientists have found that the genome of the fruit fly contains the entire genome of a bacterium called Wolbachia. Foreign DNA is also found in humans: for example, the syncitin gene, which is involved in the structure of the placenta. Studies suggest that the building instructions for this protein were introduced into the genome of our ancestors by a virus 25 to 40 million years ago. Some researchers believe that half of our genome comes from viruses.

In addition, two types can merge into one. Around 14 percent of all plant species were created in this way, estimates Loren Rieseberg from the University of Vancouver. This frenzy makes it difficult to call one species the descendant of another, because part of the genome may be derived from one species while other genes were contributed by a second or third species. Evolution can hardly be represented as a tree, at most as a dense network.

3. FROM WHOM THE DOG COMES FROM

Darwin was also wrong on some details. So he was convinced that the dog descended from fox, wolf and coyote. Today we know that it is only descended from the wolf. It was the other way around with the domestic chicken. Darwin was convinced that he had recognized the sole ancestor: a particular type of combed grouse that was domesticated in Asia about 5000 years ago. It is now clear that two different species contributed to the genetics of the domestic chicken.

If you consider what was still unknown in Darwin's time, it is all the more impressive how many things he was right about. Because Darwin's world was different from ours. Take continental drift, for example: In Darwin's time, it was not yet known that the continents were moving. The idea was not widely accepted until the second half of the 20th century. In order to put the fossil finds on different continents together into a meaningful story of life, it is enormously important.

Viruses had not yet been discovered either, and bacteria had not yet been identified as pathogens. Living beings were mainly plants and animals. Today we know that much of all life on earth is unicellular. Plants and animals make up less than 20 percent of the biomass on our planet.

His mistakes do not have to diminish the respect for Darwin. "Darwin mastered the knowledge of his time brilliantly," says Kutschera. Accusing him of not knowing certain things is like accusing Mozart of not having composed late Romantic sonatas.

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