Greatest Show from Darwin. 14-speed of evolution

To the beginning: http://proza.ru/2022/06/26/1108

-14-
The speed of evolution.

If the rate of evolutionary change is the same for all living organisms, then what should we do with all these horseshoe crabs that have been "so careless that they don't evolve at all" since the time of their fossil ancestors?
You can get off with a common phrase that, they say, the theory that has no exceptions is bad. Accordingly, the theory that has these exceptions in abundance is good. But exceptions to exceptions are different. Some inexcusable fallouts from the great evolutionary process can no longer be explained by simple exceptions to the rules. They are so blatant that they involuntarily suggest the idea: is the evolutionary process not finite? Well, at least in some cases. For example, when a certain creature has reached such perfection in the struggle for resources and, in general, in the matter of survival, that further improvement for this species does not make sense.

However, such an assumption is inexcusable for all those who perceive the living world through the prism of natural selection. After all, natural selection is an arms race in which every newly mutated creature competes with all the others who have not received such useful weapons. The competitive struggle for survival has no end. It is eternal! At least to the same extent that peace on our planet is eternal.

On the other hand, how can you win the race for survival from those who have already adapted perfectly? After all, they have already passed through the sieve of natural selection, which means they already know quite good chances of survival. Yesterday their chances of survival were higher than everyone else's, and today new mutants have come with even greater chances. So?

Not quite. According to the theory, the evolutionary step is very small, and any noticeable advantage does not arise immediately, but as a result of a series of changes that take more than one generation to develop. So the chances of new mutants to survive are no greater than those mutants who have already adapted perfectly. These chances, of course, will increase when new mutants improve newly acquired adaptations or acquire additional mutations, which, according to the theory, will not happen immediately.

And here's another question: how is it better to survive? After all, life is one and no one has managed to die twice. An increase in life expectancy will not work here. For evolution, it only matters to reach puberty in order to have a chance to leave offspring.

In fact, we are talking, of course, about purely statistical survival. Let's say we have a hundred hypothetical rabbits and one of them got a useful mutation. Small, but very useful. Let's estimate the benefit of this mutation from good stocks at 5-10% of the total ability of rabbits to survive. Further, let's assume that exactly half of the offspring of rabbits previously managed to survive to puberty, and the birth rate averaged ten rabbits. It turns out that not five, but from 5.25 to 5.5 rabbits will "survive" from the offspring of the mutated rabbit.

So this advantage of a quarter or half of a rabbit in the future will displace all other rabbits from the population. Purely arithmetically, it's great that rabbits are so prolific, because in the case of, say, elephants, evolution has to deal with hundredths or even thousandths of a baby elephant, no matter how cynical and stupid it sounds.

But now it becomes clear how important millions and millions of years are for evolution. The rate of propagation of beneficial mutations can easily compete with the rate of their occurrence. On the other hand, changes in climatic conditions on the planet, migration, the appearance of new predators or the disappearance of familiar foods can seriously affect the rate of spread of a beneficial mutation.

It is also worth remembering that in the process of evolution, a living organism becomes more complicated. Judge for yourself, any mutation is a mistake, a kind of malfunction in the inherited information. For a single-celled organism, it is quite possible that even every second mutation will be a step forward, when, as for a complex organism, very few mutations can be useful. There are too many interconnections that allow a living organism to exist as an integral system, so that some mutation, even if it would seem quite suitable for some individual organ, would not cause deterioration in interaction with its other organs.
In other words, any changes can create an imbalance in a balanced system. Consequently, an immeasurably greater number of random mutations will be required to improve a complex organism compared to the number that was quite enough for the evolution of a simple one.

For clarity, let's imagine something simple from the world of technology. For example, a cart. I am not an expert in the history of the evolution of the cart, but I will assume that the first of them were two or even one-wheeled. Adding another one or a pair of wheels will increase the stability of the cart. Further addition of wheels is unlikely to improve the driving properties of this simple device. Although they will not make the cart less suitable globally.

The situation is worse with more complex devices. If, for example, you try to adapt the same wheel to an airplane or a space rocket, then this can cause a catastrophe. Just imagine the task of improving a space rocket. Moreover, imagine that this task was set before you, without giving, at the same time, elementary education, drawings, diagrams and everything that developers usually use. How many spaceships do you think should crash before some even minimal improvement works?

So, as the body becomes more complex, more random mutations are required to get at least one useful one. Accordingly, the rate of evolution with the same progression should slow down? The speculative phrase the crown of evolution in this regard becomes quite real, since at some point in time the speed of evolution should slow down so much that it can be confidently rounded to zero.
Of course, any decent mathematician could make an equation that would take into account the most significant factors affecting the speed of evolution. Not considering myself a decent mathematician, however, I can assume with a high degree of confidence that as the complexity of a living organism increases, the number of harmful mutations per useful one should grow exponentially.

This is on the one hand, and on the other, the complication of living organisms can predictably lead to an increase in the number of mutations. Indeed, having a unicellular structure, you can expect a few errors in the inherited genes. Having not just a multicellular organism, but an organism that unites many interconnected organs, it is quite logical to expect that the number of errors in hereditary information can increase many times and, therefore, compensate for the inevitable slowdown of evolution based on random mutations.

What can I add here? Perhaps the mathematical formula for the speed of evolution will give an answer to why horseshoe crabs and coelacanths have practically not changed over hundreds of millions of years. I really hope that the complexity of their organism is not the limit for improvement by random mutations and there is some simple explanation for their complete unwillingness to evolve.

Otherwise, a reasonable person would have no chance of being born at all, and then it would be convincingly proved that in fact we all live according to different laws governed by the Matrix.

* - I apologizes for my English. I would be grateful for the corrections.

Next:http://proza.ru/2022/07/12/1028