Monday, April 23, 2012

What is Natural Selection?

Natural selection is the most important mechanism of evolution, and it makes the childish god fantasy unnecessary. A god fairy who never had anything to do is a fairy who doesn't exist.

Natural selection is an extremely simple concept so of course most Christians are unable to understand it. They think it's a completely random process therefore evolution is impossible. Of course evolution would be impossible if it was random but there's nothing random about the natural selection of favorable mutations. The mutations are random but the selection of what works is not random. Selection occurs when a creature has what it takes to become a parent and a grandparent. Its genes get passed on to future generations, while another creature without the favorable mutation has zero or fewer descendants. Its genes disappear from the population. That can not be called random or chance. Small changes are cumulative. Small improvements every generation can over a vast amount of time and thousands of generations very gradually develop a new species, for example modern human apes and modern chimpanzee apes which developed from the same common ancient ape ancestor. These two lineages evolved differently because they lived in different environments.

My experience is the more I learn about this mechanism of evolution the more interesting it becomes. I learn why fish who live in caves lose their eyesight, and why the ancestors of whales lost their legs. I learn about how evolution works with what it has, because evolution by natural selection can't develop a new species from scratch, unlike the god fantasy called magical creationism. And this fact, natural selection has to work with what nature gives it, is a source of some of the most powerful evidences for evolution.

In America (population 300 million) there are about 150 million idiots who deny evolution, or if you want to include the morons who think a god's magic wand is a mechanism of evolution, then about 250 million American idiots are evolution deniers. These science deniers are usually called creationists because instead of accepting 150 years of amazing scientific discoveries which have made evolution the strongest fact of science, they have a ridiculous fantasy about a god fairy who waved a magic wand to create every creature out of nothing (or waved its wand to invent, use, or guide evolution as if natural processes require the magic Jeebus man to work properly).

Christian idiocy in America is out of control. Choose 10 Americans randomly and virtually all of them are likely to be creationists.

An interesting thing about American evolution deniers, besides their breathtaking stupidity, is they know absolutely nothing about the science they are denying. They ignore the evidence (which they wouldn't be able to understand anyway) and they assume their ignorance is equal to the education and experience of all the world's biologists, which reminds me of this famous quote:

There is a cult of ignorance in the United States, and there always has been. The strain of anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that "my ignorance is just as good as your knowledge."
-- Isaac Asimov

Creationists go way out of their way to know nothing. Not often but sometimes they will read a book about evolution. They don't read to understand. Instead they try hard to not understand anything, preferring to invent problems with evidence that has no problems. They are looking for excuses to deny what they're reading. It's fair to ask what the heck is wrong with these imbeciles. How is it possible for a person to prefer something as idiotic and childish as magical creationism instead of more than a century of scientific progress? How can anyone be so brain-dead fucking stupid?

It's obvious something terrible has happened to evolution deniers that has made their small brains permanently defective. It doesn't help that they were born in an idiot country where it seems virtually everyone is an uneducated moron. Almost always the creationist's parents are extremely stupid, so of course the person was trained to be equally retarded. Even worse than all the burning stupidity is the intense religious brainwashing that begins as soon as the victim learns how to walk. After several years of this child abuse the victim is convinced scientists are evil people who can't be trusted. They have been trained to believe that denying the magical creation fantasy is a terrible sin and the punishment is eternal torture in a magical hell. These unfortunate people have been trained to be insane.

I would be surprised if a creationist ever gets this far. Besides being cowards who are terrified of reality, creationists are very sensitive. Instead of complaining about being called retards, they should consider the possibility they really are retarded and then do something about it. They should grow up, educate themselves, and face facts. It's a terrible waste of a life to spend it believing in bullshit while denying the most interesting natural process of science. These people don't even know what they are (they're apes). They will drop dead pretending they are special creations of a magical god who will send them to a magical heaven. It's disgusting that they're so sick and it's even more terrible that these Christian scum infect their own children with their incurable mental illness. Even worse, their Christian war against science education can destroy the minds of everyone else's children. I see absolutely no difference between a Christian and a terrorist. They are both trying to destroy my country.

National Geographic  Magazine defined natural selection at

The gist of the concept is that small, random, heritable differences among individuals result in different chances of survival and reproduction—success for some, death without offspring for others—and that this natural culling leads to significant changes in shape, size, strength, armament, color, biochemistry, and behavior among the descendants. Excess population growth drives the competitive struggle. Because less successful competitors produce fewer surviving offspring, the useless or negative variations tend to disappear, whereas the useful variations tend to be perpetuated and gradually magnified throughout a population.
Natural selection is the gradual, non-random, process by which biological traits become either more or less common in a population as a function of differential reproduction of their bearers. It is a key mechanism of evolution.
Variation exists within all populations of organisms. This occurs partly because random mutations cause changes in the genome of an individual organism, and these mutations can be passed to offspring. Throughout the individuals’ lives, their genomes interact with their environments to cause variations in traits. (The environment of a genome includes the molecular biology in the cell, other cells, other individuals, populations, species, as well as the abiotic environment.) Individuals with certain variants of the trait may survive and reproduce more than individuals with other variants. Therefore the population evolves. Factors that affect reproductive success are also important, an issue that Charles Darwin developed in his ideas on sexual selection, for example.
Natural selection acts on the phenotype, or the observable characteristics of an organism, but the genetic (heritable) basis of any phenotype that gives a reproductive advantage will become more common in a population (see allele frequency). Over time, this process can result in populations that specialize for particular ecological niches and may eventually result in the emergence of new species. In other words, natural selection is an important process (though not the only process) by which evolution takes place within a population of organisms. As opposed to artificial selection, in which humans favour specific traits, in natural selection the environment acts as a sieve through which only certain variations can pass.
Natural selection is one of the cornerstones of modern biology. The term was introduced by Darwin in his influential 1859 book On the Origin of Species,[1] in which natural selection was described as analogous to artificial selection, a process by which animals and plants with traits considered desirable by human breeders are systematically favored for reproduction. The concept of natural selection was originally developed in the absence of a valid theory of heredity; at the time of Darwin's writing, nothing was known of modern genetics. The union of traditional Darwinian evolution with subsequent discoveries in classical and molecular genetics is termed the modern evolutionary synthesis. Natural selection remains the primary explanation for adaptive evolution.

Darwin C. (1859) The Origin of Species
''........can we doubt (remembering that many more individuals are born than can possible survive) that individuals having any advantage, however slight, over others, would have the best chance of surviving and procreating their kind? On the other hand, we may feel sure that any variation in the least injurious would be rigidly destroyed. This preservation of favourable variations and the rejection of injurious variations, I call Natural Selection'
or in a most concise definition from contemporary Biologist Richard Dawkins
"the non-random survival of random variants."
The rest of this post are quotes about natural selection from the books of four biologists. Click the links if you want to buy the books. I recommend all four books but my favorite is Jerry Coyne's Why Evolution is True because it's interesting, easy to understand, and not tedious to read.

On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life by Charles Darwin

Why Evolution is True by Jerry Coyne

The Making of the Fittest: DNA and the Ultimate Forensic Record of Evolution by Sean B. Carroll

The Greatest Show on Earth: The Evidence for Evolution by Richard Dawkins

 "I have called this principle, by which each slight variation, if useful, is preserved, by the term Natural Selection"
-- Charles Darwin

"In the struggle for survival, the fittest win out at the expense of their rivals because they succeed in adapting themselves best to their environment."
-- Charles Darwin

Dishonest Christian assholes love to quote-mine the following Darwin quote. They end their quote mining at "absurd in the highest possible degree." This is typical Christian dishonesty. Christian scum are constantly spreading lies to defend their dead magic Jeebus man. I never met a Christian who wasn't a dishonest stupid fucking asshole.

"To suppose that the eye, with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest possible degree. Yet reason tells me, that if numerous gradations from a perfect and complex eye to one very imperfect and simple, each grade being useful to its possessor, can be shown to exist; if further, the eye does vary ever so slightly, and the variations be inherited, which is certainly the case; and if variation or modification in the organ be ever useful to an animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, can hardly be considered real."
-- Charles Darwin

But Natural Selection, as we shall hereafter see, is a power incessantly ready for action, and is immeasurably superior to man's feeble efforts, as the works of Nature are to those of Art.
Charles Darwin, The Origin of Species

When we no longer look at an organic being as a savage looks at a ship, as something wholly beyond his comprehension; when we regard every production of nature as one which has had a long history; when we contemplate every complex structure and instinct as the summing up of many contrivances, each useful to the possessor, in the same way as any great mechanical invention is the summing up of the labour, the experience, the reason, and even the blunders of numerous workmen; when we thus view each organic being, how far more interesting - I speak from experience - does the study of natural history become!
— Charles Darwin

 Multiply, vary, let the strongest live and the weakest die.
Charles Darwin, The Origin of Species

Nothing is easier than to admit in words the truth of the universal struggle for life, or more difficult--at least I have found it so--than constantly to bear this conclusion in mind.

natural selection: The nonrandom, differential reproduction of alleles from one generation to the next. This usually results from the carriers of some alleles being better able to survive or reproduce in their environments than the carriers of alternative alleles.
-- Jerry Coyne

allele: A particular form of a given gene produced by mutation. For example, there are three alleles at the protein-coding gene that produces our blood type: the A, B, and O alleles. All are mutant forms of a single gene that differ only slightly in their DNA sequence.
-- Jerry Coyne

Chance alone cannot explain the marvelous fit between individuals and their environment. And it doesn't. True, the raw materials for evolution--the variations between individuals--are indeed produced by chance mutations. These mutations occur willy-nilly, regardless of whether they are good or bad for the individual. But it is the filtering of that variation by natural selection that produces adaptations, and natural selection is manifestly not random. It is a powerful molding force, accumulating genes that have a greater chance of being passed on to others, and in so doing making individuals even better able to cope with their environment. It is, then, the unique combination of mutation and selection--chance and lawfulness--that tells us how organisms become adapted.
-- Jerry Coyne

Some day in the future when I have more time I will finish this post with more quotes from Coyne and quotes from Carroll and Dawkins about natural selection.

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