Tuesday, April 9, 2013

CH11: Doom Rivals





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Rival Theories

         Rival theories are those opposing to Darwinism. In this chapter, we shall try to explain life and ‘adaptive complexity’ using these theories. We shall see that these theories cannot explain life as well as Darwinism. These theories are just doomed rival theories. 

Embryology

Embryology is a study of the development process of living things from a single cell to an adult.  There are two school of thoughts when it comes to embryology:


  1. Preformationism or blueprint theory: This school of thoughts believes that an adult was pre-defined. Traditional preformationists believe that a sperm is a tiny version of an adult. When a sperm meets an egg, it just scales up in size, and become an adult. Modern preformationists, on the other hand, believe in blue print. They believe that DNA contains information to recreate an adult, just like when a string of digital information can be used to construct a photo. 
  2. Epigenesis or recipe theory: This school of thought believes that there is a recipe containing instructions (i.e., in DNA) to create an adult. This is like you have a recipe to bake a cake.  The instruction does not tell you what every bit of cake should look like (e.g,. color, taste, softness). It does tell you how to mix ingredient and how to bake (e.g. temperature) to get a decent cake. 

The blueprint theorists believe that there is a blueprint or a template to create adult. You can crate exactly the same adult if you follow the blueprint. This is like building a house based on a blueprint.
Epigenesis does not have template to create an adult. However, it does have instructions to create adults. If you follow, the instruction, you will create not the same but similar adult.
Today, most biologists believe in epigenesis. This is partly because the embryonic process can not be reengineer. You can’t simply look at a final product and know what stored in DNA. If the embryonic process is carried out via a blueprint, we should be able to edit the blueprint. We can remove the roof from the blueprint of a house, and the engineer will build a house without any roof. But we can’t edit DNA, and we don’t expect the embryonic process to develop an adult with one eye.
But, from time to time, we do see mutated adults. This is not because of someone has edited their DNA. It is because of inevitable mutation over the entire population. If we use the analogy to baking cake above, mutation would be like changing ingredient. The change affects not just a portion (not like a house with mission roof), but the entire cake or body.

Lamarckism

Lamarckism is developed prior to the time of Charles Darwin. Todays, only two of all its principles still survive as ‘neo-Lamarckism’: The principle of use and disuse, and the inheritance of acquired characteristics.

The Principle of Use and Disuse

This principle states that whatever gets used will grow and whatever isn’t used will wither. We see it quite often when you workout. When you try to build muscle by lifting weights, you basically breaking your muscle. When your body heals your muscle, the muscle gets bigger and stronger.
However, this principle applies only to simple stuff such as muscle. It cannot not be applies to more complicated things like an eye. It wouldn’t make sense to claim that we will have better eyesight if you exercise our eyes frequently.

The Inheritance of Acquired Characteristics

This is to say that whatever you have experienced in life will be passed down to your children. If you built strong muscle, you would inherit strong muscle to your children. Giraffe has a long neck, not because of natural selection, but because of that they’d tried to exert their neck muscle for generations.
A lot of people want to believe in ‘inheritance of acquired characteristic.’ It’s comforting to know that what you do in life can be passed down to your child. If you obtain a certain skill, your child will have that skill too. If you love this political party, your child will too. But, as you might already know, that’s not always the case.
If the inheritance of acquired characteristics is true, evolution would be quite destructive process. We, humans, accumulate defects (e.g., scar, high cholesterol level) over time. According to this principle, we are very likely to pass on these defects to our children. Our children would tend to do the same. Down the generation, we should expect that all babies would be born with a load of defects, and finally all babies would die at birth. Humans should have become extinct a long time ago.

“Lamarckism isn't a rival to Darwinism at all. It isn't even a serious candidate as an explanation for the evolution of adaptive complexity. It is doomed from the start as a potential rival to Darwinism.”
Most modern evolutionists do not believe in Lamarckism. Rather, they believe that evolution happens due to mutation and natural selection.

Other School of thoughts

There are few other schools of thoughts related to evolution.

Neutralism

Neutralism believes that the change at the molecular level is random and not subject to natural selection. Selectionism, on the other hand, believes strongly in natural selection. They believe that natural selection has great influence even at the molecular level.

Mutationism

Mutation refers to random changes. Here are a few characteristics of mutation:
Mutation is random. The change has equal odds of getting  better or getting worse.
Mutation is induced by physical events, e.g., X-rays or other genes
Mutation is non-uniform over cells. Some cells (i.e., hot spot) have high mutation tendency. Others have low mutation tendency.
Mutation in one direction might not be as likely as the mutation in the reverse direction.
Mutation does not happen out of thin air. It usually builds on embryonic process.
Darwinism believes that mutation gives 50-50 chances of being better or being worse. The role of natural selection is then to allow only those whose mutation improves the odds of surviving to live longer.
Mutationists do not believe in natural selection. They believe that every living thing improves because of mutation only. They did not ask the key question: “How do living things know what is ‘better’?” Without natural selection, all living things should have equal odds for being better and worse. On the average, they should make no improvement.

Natural Selection or Selecting Natural

This school of thought believes that mutated animals select fitting environment which is most suitable for them. Humans is an example. Humans see only ‘visible’ light, which contains colors ranging from violet to red. Even if we cannot see infrared nor ultraviolet, we are quite fit to survive. If our eyes can see only infrared, this school of thought believes that, we would have found another way to use our eyes. So, it is not the nature that has given us these eyes. It is us who choose how to use these eyes.
The problem with the denial of natural selection is that there are just too many mutating possibilities. Suppose we can mutate only a bit to generate a mutant in each generation. In 100 generations, there will be 1030 different mutated version of us. These different 1030  species cannot possibly find 1030 types of environment in this world to live happily.

Conscious Designer

This is arguably the most ancient belief. It states that there must have been a creator--i.e., God or Deity--which creates all things. But, even modern theologists do not believe in instantaneous creation. What they do believe in is ‘guided evolution’. They believe that the roles of Deity is to influence us to do this and that. It is our actions which lead to mutation and evolution.

“The one thing that makes evolution such a neat theory is that it explains how organized complexity can arise out of primeval simplicity.”
Perhaps we might have forgotten to ask one of the key questions. If we were to believe in conscious designers, we had to ask ‘who design the designer?’, ‘who design the designer of the designer?, and so on. Then we kindda run into the deadend. We can ask this question over and over again, and yet we might never get the answer.

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Book or Audiobooks?

Personally, I prefer audiobooks. It's fun, and I can listen when I'm doing something else. It also makes other activities (e.g., jogging) a lot more fun. For more detail about audiobooks, please read [this post].

There is one more reason that may encourage you to go for the audiobook version. You can get it now for FREE. Audible offers you a free trial for 14 days. Even if you get the book and cancel the subscription right away (so that you don't have to pay), you can keep the book. And, don't worry if you lost the audiobook file. Just log into audible.com. You can keep downloading the over and over again.
About the summary: It takes time to finish up a book. And, when you do, sometimes, you want to review what you learn from the book. If you do not make  notes as you read, you might have to go through the book once again. This can be time-consuming when you are dealing with a book. But you can still flip through the book and locate what you are looking for.

However, when the material is an audiobook, it is extremely hard to locate a specific part of content. Most likely you will have to listen to the entire audiobook once again.

This book summary will help solve the pain of having to go through the book all over again.

I am leaving out the details of the books. Most books have interesting examples and case studies, not included here. Reading the original book would be much more entertaining and enlightening. If you like the summary, you may want to get the original from the source below.

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