Tuesday, January 30, 2018

Evolution

Definitions

Evolution in biology can be defined as ”A change in the gene pool of a population from generation to generation by mutation, natural selection, and genetic drift.” We can also have a general definition for evolution, such as ”A process of gradual development in a particular situation or thing over a period of time.”

Evolution is a gradual, random, and slow process most of the time

All the living things started from a birth of a self-copying system with some kind of basic, heritable mutation. Mutations are random errors in copying. Our genes replicate themselves slowly and gradually through the generations. Gradualness is the key feature of evolution. It moves step-by-step from one stage to next. These moves compound in a very long time This process creates new structures and behaviors. And it has no reason or goal in mind. Humans have evolved from simple cells to conscious animals in billions of years. This process adapts to changes by changing itself.

All mutations have an element of luck. Genes maximize their own survival. Genetic effects have their own time and place. These effects may have to be changed by working together with other genes. Together they create chemical environments in our cells. Genes have usually many effects. Some of them are beneficial and most of them bad. Beneficial effects are likely happening later than good ones. Species change through these effects all the time, but slowly. You have to consider this slow speed of change, when you think about how human beings behave. For example, our brains and bodies have changed very little in the last 10,000 years. The environment around us has changed a lot more.

Evolution is a self-organizing system

Evolution happens by adding new strucures, feedback loops, or rules. This ability is the strongest form of a system resilience. Self-organization has rules. They tell the system itself where, how and what can be changed by adding or subtracting something from the system and the under what conditions these changes can happen. Biological evolution has simple sets of rules. It has created a complex world with wide variety of species. DNA´s genetic code has four different letters, combined into words with three letters. This pattern and the rules for copying and rearranging it has not been changed in billions of years. These rules have created a variety of failed and successful creatures.

DNA is an evolutionary raw material. It is a stock of variable information and a means for experimentation. It is used for selecting and testing new patterns. Spontaneous mutation creates variety for selecting raw aterial. Changes in the environment are testing mechanisms that determine which individuals survive or reproduce. For technological evolution, the raw material is the understanding of the science. The source of variation is creativity and the selection mechanism are the organizations that fund research or human needs.

Survival of the fittest is not the best definition for evolution

There are some misunderstandings about the evolution. The most common one is that the fittest always have the best chances to survive and thrive through time. We should talk more about the most adaptable and co-operative individuals. Fastest, strongest and biggest do not always cope with changes in the environment. Top-Down hierarchies or bigger structures have problems in coping with change. The faster the changes, the bigger the problems for these structures. Biological evolution is full of random bottom-up processes.

We talk about all the self-replicating genes that are always fighting for the available resources. Genes that are more efficient of getting themselves copied tend to replace the less efficient genes. In the long run, our DNAs become full of well-surviving genes. These genes are best for surviving in the average environment of their species. When the average environment changes, the surviving genes change too. In DNA´s point of view, the average environment is the body, in which DNA visits for a body´s lifetime. The other genes are maybe the most important aspect of the environment. They are not the only things concerning on the environment that matter. For example geographical separation can create different species, because conditions change by the changing geographical location. When the conditions in the environment change fast, we can talk about disruption. This is a model I will introduce later.

Adaptability is very important for the non-living things like companies. Their environments are in states of constant change. These changes are many times completely random. Many great inventions like penicillin have been discovered accidentally. Sometimes best solutions for the problem do not win. VHS videos beat Beta videos even though the latter one was the better technology. These examples are all around us. Many researchers have no way of knowing if they ever find anything useful. Companies that suffer from these unexpected discoveries can be the fittest before them and after these discoveries some of these companies even go bankrupt. These things happen because companies couldn´t adapt to changing environments because they are still applying the rules that worked before to the new situation.

This text is just the tip of the ice-berg about evolution. Evolution is all around us and it effects on every living thing on earth. I hope I have covered some basics in an understandable way. Please tell me, if I have failed.

Sources:

Thinking in Systems, Donella H: Meadows
River Out of Eden, Richard Dawkins
From Bacteria to Bach and Back, Daniel Dennett
The Evolution of Everything, Matt Ridley

-TT

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