Evolution, a theory that explains the origin of species, was proposed by Darwin and subsequently developed rapidly. For more than 160 years, evolution itself has also been "evolving", and in the first half of the 20th century, "the randomness of biological genetic mutations" has finally become one of the axioms of evolution with the efforts of many biologists. Biologists have modeled the evolution of this axiom and explained the causes of genetic diversity.
"The randomness of biological gene mutations" is to put it bluntly, when organisms reproduce the next generation, genetic mutations are random and directionless, and it has become an important basis for evolution. However, an international team of researchers in collaboration with the University of Davis in California, usa, and the Max Planck Institute in Germany published a paper in the journal Nature, which found through studies of Arabidopsis thaliana that mutations are not born completely randomly, but rather that the regions where mutations occur have obvious regularities. This poses a huge challenge to the theory of evolution, so will it subvert it?
evolutionism
To understand this question, we must first understand, what role does "randomness of genetic mutations" play in evolutionary theory?
Most people have always misunderstood evolution. This misconception comes from "directionality", and many people believe that evolution has a "direction", such as: from low to high, from thin to strong. Darwin's theory of evolution did not say so. When Darwin studied the origin of species, through Malthusian "population theory", he understood that species could not increase indefinitely, but would be affected and limited by external factors.
Therefore, Darwin proposed that organisms will overproder in the early stages, but the number of populations will not increase uncontrolled, but will be affected by natural factors. So how does that affect it?
He believes that organisms will produce mutations in the process of reproduction, mutations are not random, there is no direction, as long as they accumulate to a certain extent, they will produce some different traits than before. External factors, namely natural selection, screen out individuals who adapt to their environment and allow them to survive. Therefore, the direction of evolution is essentially natural selection, and the randomness of mutation provides the raw material for evolution.
For example, dinosaurs were once a generation of overlords, dominating the earth for 200 million years. Later, an asteroid with a diameter of 10 kilometers hit the Earth, and the solar radiation was blocked, resulting in a large-scale death of plants, which directly led to the mass death of plant-eating dinosaurs, which became extinct due to lack of food (plant-eating dinosaurs, etc.). That is to say, if you live in the era of the extinction of dinosaurs, it is not that the more muscles you have, the stronger you are, the more you can survive, on the contrary, only those small, small animals are easy to survive due to the less energy required. Primate ancestors, for example, were small at the time, needed less energy, and eventually escaped extinction.
Later, in the first half of the 20th century, scientists clarified the "mutation" that Darwin mentioned here through research, which refers to genetic mutations, chromosomal mutations and genetic recombination, which are random and are the raw materials of evolution, and have gradually become the consensus of the scientific community, which has continued to this day.
Study in the journal Nature
In order to understand the deep law behind genetic mutations, researchers from the University of Davis in California and the Max Planck Institute in Germany found Arabidopsis, a "weed" with a smaller genome, which is relatively easy to cultivate and reproduces quickly, to study.
The researchers planted hundreds of Arabidopsis thaliana in the lab and tightly protected them so that some Arabidopsis thaliana with unfavorable mutations could survive.
According to evolutionary theory, these Arabidopsis thaliana with unfavorable mutations should be eliminated by natural selection if they are in the wild.
Subsequently, the researchers sequenced dna from hundreds of arabidopsis strains and found more than 1 million mutations. So the question is, what pattern do they find in these mutations?
If the "randomness of genetic mutations" in evolution is true, then the result that researchers should get is that these mutations are randomly distributed. In fact, the researchers found that mutations are not randomly distributed, and there are some specific regions where the mutation rate is significantly lower, especially the probability of mutations in necessary genes that play a decisive role in biological life activities is significantly lower than that of other genes. For example, genes involved in cell growth and gene expression have a mutation probability that is more than 50% lower than other genes, and some essential genes are even 66.7% lower than other genes. More interestingly, the researchers also found that more than 90 percent of the mutations were related to the epigenome.
To put it bluntly, the researchers found that these mutations are not randomly distributed, but have a regular pattern, which is contrary to the "genetic mutation is random".
Does this mean that evolution is wrong?
After this paper was published, it immediately caused a sensation in the academic circle, and many scholars joined the discussion. Some scholars argue that this study cannot rule out the "survivor bias" effect. The reason is also very simple, the experiments measure the living, and those who do not survive due to the serious harm to survival cannot be measured. Therefore, the samples sequenced to are not all samples.
It has also been suggested that the regions of mutation found in the paper are themselves conserved and not easily mutated.
That said, this research needs more peers to further study, which is not the consensus of the academic community, and it is too early to assert that "the randomness of genetic mutations" is wrong. Not only that, but even if the "randomness of genetic mutations" is really wrong, it does not infer that evolution is wrong. To completely negate the theory of evolution, this paper alone is not enough.
It is believed that this paper will also arouse more scholars' attention to relevant research, and propose more perfect experiments to confirm or falsify the "randomness of genetic mutations".