Absolutely everyone has heard about evolution today. We all study the foundations of the theory of evolution in biology, as well as the fact that mankind has descended from monkeys, that there is natural selection and the strongest survive. But few people know that some scientists are interested in the process of reverse evolution and have already managed to draw some conclusions from the experiments. For example, bacteria can always return exactly one mutation back, but as they accumulate, they lose this ability.
In order to understand the intricacies and understand what it is, we need a little deeper knowledge in this area. This article will discuss whether there really is any definition of the reverse process of evolution, and whether the use in this vein of the very terms that are now accepted for convenience to denote this phenomenon is correct.
Evolution
The term itself came from the English verb evolve, which means "gradually develop."
In biology, evolution is considered to be the change of genes from generation to generation, although the misuse of this term in the media is very common. For example, when evolution and natural selection are not distinguished from each other. Sometimes they even manage to apply it to the Big Bang, which has nothing to do with it.
Charles Darwin, creating his theory, relied on the principles of natural selection and genetic mutations. Organisms gradually adapted, trying not to die in a changing and complex world, developing from generation to generation in order to survive.
The scientist believed that the process of evolution cannot go back. According to him, the species that has become extinct will not appear again, even if the necessary conditions for his life are established.
But it’s very easy to imagine (purely theoretically) that a certain mammal will again return the membranes between the fingers, just falling into the environment in which the ancestors of this species have had them for centuries. The most interesting thing is that membranes can really appear. But this cannot be called a process of reverse evolution, since when re-growing it will be correct to name what happened as regression. The fact is that this will happen differently, not in the way that the membranes once disappeared, giving way to fingers. This will be just a new step, a simplification of an existing structure, and not a return to its previous stage of development.
What is the name of the reverse process of evolution?
At the moment, there is no term bearing exactly this semantic load, which, of course, does not hinder the desire to speculate on such an interesting topic. Therefore, in this case, the incorrect use of names and definitions is permissible. For this reason, terms such as degradation, regression, and involution are often used to refer to the process of reverse evolution.
Degradation and regression
In fact, this is only the destruction and deterioration of the situation, antonyms to the word "progress", which does not mean a return to the already passed stage. These terms mean quality degradation, decomposition processes, and so on. Of course, this is not suitable for designating the process of reverse evolution, because it does not fully correspond to it.
Involution
This word often denotes the loss of any organs in the process of evolution itself, their atrophy during aging, as well as the reverse development and restoration of the organ's past properties, for example, the uterus after childbirth. Although this term is considered closer to the word "evolution", the reverse process can not be called involution officially as a phenomenon. This is only a peculiar kind of evolution, bearing certain changes.
Reversibility of evolution
According to scientists who studied bacteria and the reversibility of their evolutionary changes, the most important problem is not to prove the presence and possibility of this phenomenon, but to understand how, when and why it can occur. To understand this mechanism, scientists drew attention to bacteria and their mutations, which led to the emergence of antibiotic resistance.
To acquire resistance, the bacterium had to have five specific mutations. The aim of the experiment was to find out whether reversibility is possible in this process and whether bacteria will lose their ability to mutate and antibiotic resistance while reducing survival in a new environment. It turned out that bacteria could always go back one mutation, but the presence of four stages was already becoming critical.
That is, we are not talking about the complete reversibility of evolutionary processes, but the study of the very “point of no return" excites many scientists.