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During the past year, I was a guest on several radio call-in shows answering callers’ questions about my book, Settled Science. Some of the more popular questions were:
- “Does God exist?”
- “Did we really come from monkeys?”
- “What is evolution and how does it work?”
- “What does ‘survival of the fittest’ mean?”
Some people say they are absolutely sure God is dead. Others are just as certain He lives. Still others have no doubt God is just a figment of man’s imagination. The God question endures because only dead people might know, and they can’t tell us. Any individual or group that claims otherwise have either been misled themselves, are hallucinating, or are just pretending to know for a myriad of reasons. In my opinion, if everyone could somehow be persuaded to replace their disparate religious and anti-religious certainties with one strong unifying hope that a loving and merciful God does exist in an eternal spiritual world, who might assist each of us while we are living and might provide us with an eternal life of our own choosing after we die, much of the fear, anxiety, and hate in the world would disappear. I don’t think religious unification will ever be possible for the following reasons:
- Without all the economic activity generated by thousands of competing religious and anti-religious groups, and all the businesses that support and depend on them, the world’s financial system would collapse.
- Truly religious people are not satisfied just believing they might get to heaven, they strongly need to believe others who hold different beliefs won’t, which explains why every religious group I’m aware of insists its pathway to heaven is the only way, and all competing ones lead straight to the other place.
- Argumentative people, religious or not, love to argue about religion because they know most of their affirmations, testimonials, and denials cannot be proved or disproved. So exchanging their strong certainties(real or feigned) for consensual hope would eliminate anything religious to argue about, so, in my opinion, they won’t.
Replacing expensive, sometimes boring, and outmoded religious habits, and dour secular attempts to restrict them, with cheerful visits to nursing homes, and generous donations to the Special Olympics and St. Jude Children’s Hospital would at least improve our dispositions, don’t you think?
Trying to rationally debate competing “messages” from God, offered by God’s many earthly “messengers,” is not only futile, the debates often lead to violent conflicts when zealous followers of the “messengers” try to convert others. As long as many people ignore their conscience and willingly surrender their liberty for a few biscuits and an AK-47, and others set aside their reason and eagerly trade their hard-earned resources for smiles, hugs, and soothing lies, there will be no shortage of ‘messengers’ offering them. Please read my other commentaries—“Ah, The Comfort of Knowing,” “Change The Creator’s Rules,” “Theistic Evolution: God’s Plan,” and “Slippery Slope of Irrational Hope”—and see if you agree with any of them.
The monkey question is humorous to some but disturbing to others. Humanity’s most recent ancestors were not monkeys. They were apes. Read my commentary “What Is A Human Being” to see who all our other ancestors were, all the way back to the first one-celled bacterium that formed in the sea 3.5 billion years ago.
Evolution is usually defined as a change in the gene pool of a living species caused by a change in its environment. Members in the species’ population that have physical or behavioral traits better suited to a significant environmental change will increase their relative positions in the population . In time, most members will inherit these more suitable traits giving the species a competitive advantage over others.
The term “survival of the fittest” was made popular by Charles Darwin when he heard the term applied to his theory that a process of “natural selection” determines species winners and losers based on their relative fitness for their environment. A more accurate term would be survival of the fit enough. Today biologists know natural selection operates at all levels of living systems, not just at the species level. The highly specialized cells in each of our body organs choreographed by specific genes and master genes to know precisely when and where to go, and what to do when they get there, didn’t attain this sophistication in one step. Their primitive ancestors first made their debut in the simple organelles of our flatworm ancestors over half a billion years ago.
All members of every species on Earth have evolved a way to survive long enough to pass on their genes to a new generation. In order for the species to survive each new generation needs high numbers of offspring because many will die before they can pass on their genes, and many will be unable to. Offspring equipped with the most efficient (fittest) traits for their environment have the best chance to survive but a few with some less efficient ones sometimes can as well, depending on which ones and the extent of their unfitness. Natural selection is the unconscious invisible hand that “decides” which traits must be the fittest, which of the almost fittest can be “tolerated,” and which ones must be discarded.
All traits, fit or otherwise, of any living thing was determined by the genes it inherited from other living things. On very rare occasions, when living cells are making copies of its genes to pass on to the next generation, mistakes (mutations) occur that change the genes. If the changed genes are helpful, or not too harmful, to the offspring receiving them, the next generation will have individuals in it with different traits who can pass them on to the next generation and so on. If the mutations (changed genes) cause immediate or early death to offspring or adversely affect the offspring’s ability to reproduce, natural selection discards them. Depending on how harmful the mutations are, their disappearance from the gene pool can take place quickly or take many generations over a very long time. In time, surviving species will be composed of individuals having multiple variations of the same trait but a large majority will be equipped with the most efficient (fittest) ones.
Many people still skeptical of Darwin’s theory ask “…if natural selection is supposed to favor genes that are best for us, why are there so many genes that cause mental disorders and low intelligence in the population, and why has natural selection not gotten rid of them?” The reason there are so many less than fit human brain gene variations is because there are so many opportunities for the mutations that produce them, and natural selection’s “decisions” to “tolerate” some and limited opportunities to remove others.
The entire human genome contains about 25,000 genes and half of them are involved with the brain. During ongoing mutations over millions of years natural selection slowly guided the development of a larger, thicker, and more efficient human brain by selecting (retaining) the mutations of genes that aided this development and discarding harmful ones. At some point along this long journey, a combination of mutations produced a startling result: rudimentary cognitive thinking. Having this ability was so advantageous that any other mutations enhancing this ability were quickly selected even though some of them also produced psychological disorders. The speed of selection accelerated when humans, using their more intelligent brain, saw the advantages of living in larger groups. Living in larger groups increased competition between individuals for resources and mating partners, making intelligence even more important. These developments increased pressure on natural selection to accelerate selection, which allowed many psychological disorders to remain in the gene pool.
In order for natural selection to cull any genetic disorder from a population, mental or otherwise, the disorder must be one that restricts or reduces the number of surviving offspring. Many psychological disorders are not serious enough to affect reproduction or survival rates, and some of the more serious ones only develop in individuals after child bearing age when natural selection is no longer operating. Furthermore, some of the most serious psychological problems that do inhibit reproduction, or shorten lives, are associated with parts of the brain that evolved so recently, in evolutionary time, that natural selection has not had enough time to do its work. Again, when less efficient genes are not immediately lethal to the offspring receiving them, the number of generations required by natural selection to remove them from the population is inversely proportional to how harmful they are on the number of surviving offspring.
Read Settled Science to better understand how mutations, in combination with natural selection and genetic drift, changed a one-celled bacterium into all the living things that have ever existed on Earth.
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