What is evolution?

Evolution

In its most basic form, evolution is genetic change within a population - specifically changes in the allelic frequencies of said population. Like gravity, this is an easily observed fact, having been observed in history and replicated today; evolution is both a fact and a theory.

Evolutionary thought can be traced back to classic Greece, but it is most commonly associated with Charles Darwin. In fact, Darwin only described one of the mechanisms that now are known to guide evolution, that is Natural Selection. He also put forward his idea that all the species have originated from a common ancestor and changed over time to the present situation. But it is important to note that evolutionary theory was not unique to Darwin; he simply put together puzzle pieces that others gathered throughout history.

In short, Natural Selection is the process by which favorable heritable traits become more common in successive generations of a population, and unfavorable heritable traits become less common due to differential reproduction. That is: given a certain population, those individuals who are more fit to the selective pressure(s) by their habitat (in a given time and space) will leave more descendants (with the favorable traits that allowed them or reproduce) than those less fit.

This means that for Natural Selection to act, a population must be composed by individuals that differ in their traits. This variation among members of the same species is evident and arises via mutations.

The other known mechanisms for evolution are: Genetic Drift, Genetic Flow and the aforementioned Mutation. Other common concepts are Artificial Selection and Sexual Selection (Both special cases of Natural Selection) and Bottleneck Effect and Founder Effect (Special cases of Genetic Drift.)

Evolution is the change of species through time. Process of change with time during successive generations among organisms.

Evolution is the explanation for the development, adaptation and diversity of life, as well as the morphological similarities between different kinds of life, such as the similarities between mammals and other "families" of species.

A minor quibble:

Evolution is the change of a species over generations. Time is incidental. Bacteria evolve over a matter of hours while humans need at least twenty years to create a single generation. It is the number of generations that matters most because each individual animal does not evolve no matter how much time passes. It is changes in DNA that get passed on through reproduction that matters in evolution.

A Major Quibble

Evolution is a theory. Gravity is described under the proved scientific Law of Gravity. The two are quite different things.

Evolution has not been proved. This is why it is correctly referred to as a theory. Gravity is a proved Law of science with no known exceptions and no contrary evidence. It is also repeatable and observable, which evolution is not.

It is thus both incorrect as well as grossly misleading to refer to gravity and Evolution in the same breath as if they are equal. They are not.

A quick Note:

In science, a Theory is a well established body of science that has a negligible chance of being disproved. It's as good as science gets - a huge deal in the scientific community. Laws are mathematical relationships, usually part of a theory. Law does not mean proved. Gravity is not proved. Nothing in Science is proved. It's tested, and supported by evidence.

Evolution is a False Belief in Some Opinions

According to Richard Dawkins:

"I believe, but I cannot prove, (emphasis added) that all life, all intelligence, all creativity and all "design" anywhere in the universe is the direct or indirect product of Darwinian natural selection."

Source: Roger Highfield, "Science's 'scourge of believers' declares his faith in Darwin." Daily Telegraph, 5 January, 2005, p.10.

This is also clearly demonstrated in the emotional way in which people defend their 'faith', since it is such an integral underpinning of atheistic naturalism.

Context matters

I believe, but cannot prove, that I have a cold. I am convinced that I have one because I am sneezing, have a runny nose and generally feel lousy but haven't improved or worsened in the last two days. It is possible that rhino virus is not the culprit and I am certainly open to evidence pointing either way. However, for the time being I feel reasonable accurate declaring that it is a cold. This is one form of "belief." (I have chosen this example because it can be proved to be true or false, by testing for the virus. But, since I lack the equipment I cannot prove it. There is a valid, scientific test even if I do not have access to it right now (or if it hasn't been invented yet.) This is different from the bottom example because the believer there has no test, but merely relies on circumstantial evidence as sufficient.)

I believe, but cannot prove, that there are mermaids. People all over the world have believed in mermaids for thousands of years. There are ancient books describing mermaids and there are mermaids in many cultures. It is foolish to discount all this just because we haven't seen one with a submarine. I have no direct evidence pointing to them but I believe they exist. We should except it as a working hypothesis and place the burden of proof on the disbelievers. This is another form of belief.

Belief in evolution is in the first category while religious faith is in the second. There is nothing really wrong with unsubstantiated beliefs as long as you recognize the important differences.

Answer

Evolution is indeed an unsubstantiated belief, as Dawkins stated, although he is undoubtedly a firm believer in it.

The Laws of Science are against it, like the Law of Biogenesis.

Many facts of science are against it, indeed making it impossible.

Evolutionary scientists acknowledge that we don't see evolution happening. Nor do we see it in the fossil record. It is thus not at all the same as a common cold which I can see, feel and test. In other words it is part of a philosophy, or, as Dawkins admitted, a belief, but is not proven.

Important note

There is already a good definition of evolution above, but several people have posted false information as well.
Instead of participating the endless claims and arguments about evolution, I will simply state undeniable facts about the scientific community. The US National Academy of Science, and Albanian Academy of Science, and Argentinian National Academy of Science, and Australian Academy of Science, and Austrian Academy of Science, and Bangladesh, and Belgium, and Bosnia, and Brazilian, Bulgarian, Canada, Chile, Chinese, Taiwan, Columbia, Croatian, Cuba, Czech, Danish, Egypt, France, German, Greece, Hungarian, Indian, Indonesian, Iranian, Irish, Israel, Italy, Japan, Kenya, Kyrgyz, Latvian, Lithuanian, Macedonian, Mexican, Mongolian, Moroccan, Netherlands, New Zealand, Nigerian, Pakistan, Palestinian, Peru, Philippines, Polish, Senegal, Serbian, Singapore, Slovak, Slovenian, South Africa, Spain, Sri Lanka, Sweden, Swiss, Tajikistan, Carribian, Turkish, Uganda, UK, Uzbekistan, Venezuela, Zimbabwe, and more....

Every National or International scientific academy on earth with a public position on evolution, every single one has the official position that evolution is valid well supported science conclusively supported by the evidence, and rejecting every single criticism against evolution thus far as scientifically refuted or just plain false. There is no national or international academy of science that considers any of the anti-evolution claims above to be true, no national or international academy of science that considers any of the anti-evolution claims above to have any scientific validity. People can post anti-evolution claims all they like, every significant scientific body on earth agrees that those claims are just plain false. People can post all the anti-evolution arguments they like, every significant scientific body on earth agrees that those arguments those arguments have been scientifically refuted.

THOSE facts are indisputable and unarguable.
I will add a link to a typical such official scientific statement on the subject, the IAP statement on the teaching of evolution, a statement signed by the National Academy of Science of every nation in the laundry list of nations I mentioned above. Countless additional national and international scientific bodies have issued comparable official statements affirming that evolution is valid evidence supported science. All of the claims against evolution are just plain misinformation and scientifically invalid. The anti-evolution activists have no scientific credibility and no scientific support. There are only about 0.1% of people with biology degrees who dispute evolution, and they are all considered crackpots by the other 99.9% of professional biologists. The only "scientific" bodies disputing evolution are tiny private activist groups like the Discovery Institute, and they don't actually do any science. All they actually do is run public relations activism against evolution and political lobbying on the issue and fighting court battles over it. They don't do any active science! They are tiny non-scientific activists spreading misinformation.

Answer

Evolution usually means a gradual, unplanned change. For example, in computing you might argue that there has been an evolutionary move from using floppy disks - as it became common for computers to be networked, writable CD drives became cheaper people stopped using floppy disks - they didn't plan the change, it happened naturally as a consequence of external events.

Answer

Evolution, at least as it is presented in modern evolutionary synthesis (MES), is far and away the very best explanation for the way life on earth came to be the way it is today. We know by virtue of scientific facts that life on earth has been here a long, long time. Additionally, the earliest forms of life were very simple. Later, more complex forms of life arose. Modifications of the surface of the earth, like climate change, massive vulcanism, or impacts from large rocks from space, imposed conditions that forced many different species of life into extinction. As billions of years of time went by, life changed. Why wouldn't it? And modern evolutionary synthesis is considered fact as regards the scientific community. It (MES) looks across a literal ocean of facts and bits of data, and then pulls the whole thing together with an explanation. Note that the facts are already there, and MES comes along late to explain how all the facts are tied together. The curious investigator will use the links below to discover supporting facts and new ideas.

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First answer by Getacar. Last edit by Quirkyquantummechanic. Contributor trust: 2269 [recommend contributor]. Question popularity: 34 [recommend question]