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117. The Amazing Brain: How it was made.

6 Jul

Most people know, or are at least aware of the idea, that our amazing brains were developed through biological evolution. I am going to try to make a clear explanation of this process. One approach is to make comparisons with easy to understand non-biological processes.

A manufactured product can evolve under the following conditions:
1. Consider a product such as a cell-phone, that has a high volume of sales.
2. This product can and will be improved in a number different ways.
3. After each modification, there is an objective measure of the product’s success.
4. The product is permanently modified if there are indications of its success with the public.

So, the procedure is to make and sell a specific improvement, say, a larger screen. If the larger screen sells more phones, then it will be included in all future versions. If sales are worse, then the improved version will be abandoned. In this way, the cell-phone will “evolve” and customers will enjoy better and better phones.

The key factors in this and other evolution are variation (which is persistent) and feedback related to the new features. And, of course, the feedback must have an effect on the persistence of variations.

In biological evolution, mutation (relatively permanent changes) occurs in a species as new DNA is created for offspring. The feedback is success in survival. If a change, such as a longer neck for a giraffe, helps giraffes to survive, then giraffes may “evolve” longer necks. Note, longer necks allow giraffes to reach more food. Natural selection (survival of the fittest) is the biological process, similar to customer satisfaction for the cell phones.

It is really remarkable that “nature” has created automatically self-improving objects like animals and plants. The improvements can take place without any human intervention. Every animal and plant on earth has developed, in this way, for billions of years.

.                           Amazing time leads to Amazing complexity
Now think about this: the amazing complexity of the human brain is based on an amazing amount of time, billions of years. Brains (and all other organs) have developed to a fantastic degree, because of a fantastic amount of time for this “evolution” process to take place.

I should also mention that in our world, there are many types evolution. Similar to natural biological evolution, is animal breeding. Here, the selection is NOT natural, but by humane intervention. As civilization developed, there have been remarkable changes in species to make them more desirable for human use. The clear effects of breeding are very supportive of the concept of natural evolution.

If you want to develop your understanding of brain evolution, do an Internet search on the words “animal nervous systems” or “animal brains” and look at the images. This will help you to see the progression. After the transition from single-celled to multi-cellular animals, rudimentary nervous systems appeared. These provided simple two-cell reflexes based on an input (sensory neuron) and an output (motor neuron). Eventually, more neurons were added to the processing and finally complex brains appeared. Some of this nervous system development is well
understood, but there is still very much to learn.

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