My "look vs. sounded" was meant as a parody of your "being vs. sounding", in that neither quip added to the discussion.
Now, don't blame me for the following, because you asked for it...
Let's start from the top.
EvolutionEvolution is usually defined simply as changes in trait or gene frequency in a population of organisms from one generation to the next. However, "evolution" is often used to include the following additional claims:
- Differences in trait composition between isolated populations over many generations may result in the origin of new species.
- All living organisms alive today have descended from a common ancestor (or ancestral gene pool).
The term "evolution", especially when referred to as a "theory", is also used more broadly to incorporate processes such as natural selection and genetic drift.
FactFact is often used by scientists to refer to experimental data or objective verifiable observations. "Fact" is also used in a wider sense to mean any hypothesis for which there is overwhelming evidence. A fact is hypothesis that is so firmly supported by evidence that we assume it is true, and act as if it were true.
Evolution is a fact in the sense of it being overwhelmingly validated by the evidence. Frequently evolution is said to be a fact in the same way as the Earth revolving around the Sun is a fact. The following quotation from H. J. Muller, "One Hundred Years Without Darwin Are Enough" explains the point.
'There is no sharp line between speculation, hypothesis, theory, principle, and fact, but only a difference along a sliding scale, in the degree of probability of the idea. When we say a thing is a fact, then, we only mean that its probability is an extremely high one: so high that we are not bothered by doubt about it and are ready to act accordingly. Now in this use of the term fact, the only proper one, evolution is a fact.'
The National Academy of Science (U.S.) makes a similar point:
'Scientists most often use the word "fact" to describe an observation. But scientists can also use fact to mean something that has been tested or observed so many times that there is no longer a compelling reason to keep testing or looking for examples. The occurrence of evolution in this sense is fact. Scientists no longer question whether descent with modification occurred because the evidence is so strong.'
Philosophers of science argue that we do not know anything with absolute certainty: even direct observations may be "theory laden" and depend on assumptions about our senses and the measuring instruments used. In this sense all facts are provisional.
TheoryScientific theories describe the coherent framework into which observable data fit. The scientific definition of the word "theory" is different from the colloquial sense of the word. Colloquially, "theory" can mean a conjecture, an opinion, or a speculation that does not have to be based on facts or make testable predictions. In science, the meaning of theory is more rigorous: a theory must be based on observed facts and make testable predictions.
In science, a current theory is a theory that has no equally acceptable or more acceptable alternative theory, and has survived attempts at falsification. That is, there have been no observations made which contradict it to this point and, indeed, every observation ever made either supports the current theory or at least does not falsify it by contradicting it completely. A revision of the current theory, or the generation of a new theory is necessary if new observations contradict the current theory, as the current findings are in need of a new explanation (see scientific revolution or paradigm shift). However, the falsification of a theory does not falsify the facts on which the theory is based.
Evolution and GravityThe terms "fact" and "theory" can be applied to evolution, just as they are to gravity. Misuse and misunderstanding of how those terms are applied to evolution have been used to construct arguments disputing the validity of evolution.
There have been many theories that attempt to explain the fact of gravity. That is, scientists ask what gravity is, and what causes it. They develop a model to explain gravity, a theory of gravity. Many explanations of gravity that qualify as a Theory of Gravity have been proposed over the centuries: Aristotle's, Galileo's, Newton's, and now Einstein's. Confusion of the terms can arise when we use a single word to describe both the observed facts and the theory that explains it. The word "gravity’’ can be used to refer to the observed facts (i.e., the observed attraction of masses) and the theory used to explain it (gravity is the reason why masses attract each other). Thus, gravity is both a "theory" and a "fact."
In the study of biological species, the facts include fossils and measurements of these fossils. The location of a fossil is an example of a fact (using the scientific meaning of the word fact). In species that rapidly reproduce, for example fruit flies, the process of evolutionary change has been observed in the laboratory. The observation of fruit fly populations changing character is also an example of a fact. So evolution is a fact just as the observations of gravity are a fact.
In biology, there have been many attempts to explain these observations over the years. Lamarckism, Transmutationism and Orthogenesis were all non-Darwinian theories that attempted to explain the observations of species and fossils and other evidence. However, the Theory of Evolution is the explanation for all relevant observations regarding the development of life, based on a model that explains all the available data and observations. Thus, evolution is not only a fact but also a theory, just as gravity is both a fact and a theory.
Gravity- Things falling is an observation of the pull of bodies towards each other.
- Bodies pulling towards each other is called gravity.
- Gravity is a fact.
Evolution- Fruit flies changing generation to generation is an observation of generational organism change.
- Organisms changing generation to generation is called evolution.
- Evolution is a fact.
Gravity- Aristotle and Galileo created explanations of the fact of gravity. These are now obsolete explanations.
- Newton's explanation of gravity is approximately correct but required refinement.
- Einstein's explanation is a refinement of Newton's explanation of gravity. Einstein's explanation is currently the most accepted explanation of the fact of gravity.
- Einstein's explanation of the fact of gravity is called The General theory of relativity.
Evolution- Lamarckism, Transmutationism and Orthogenesis were created as explanations of the fact of evolution. These are now discredited explanations.
- Darwin's explanation of evolution is approximately correct, but required refinement.
- The modern evolutionary synthesis is a refinement of Darwin's explanation of evolution, which did not include genes in its explanation. This modern synthesis is currently the most accepted explanation of the fact of evolution.
- The explanation of the fact of evolution provided by the modern synthesis is the latest and most widely accepted Theory of Evolution.
More Fact vs. TheoryThe confusion between "fact" and "theory" and the use of the word "evolution" is largely due to some authors using evolution to refer to the changes that occur within species over generations and common descent, while others use the term more generally to include the mechanisms driving the change. However, among biologists at least, there seems to be consensus that evolution is a fact:
- American zoologist and paleontologist George Simpson stated that 'Darwin...finally and definitely established evolution as a fact.'
- H. J. Muller has written, 'If you like, then, I will grant you that in an absolute sense evolution is not a fact, or rather, that it is no more a fact than that you are hearing or reading these words.'
- Kenneth R. Miller writes, 'evolution is as much a fact as anything we know in science.'
- Ernst Mayr has observed 'The basic theory of evolution has been confirmed so completely that most modern biologists consider evolution simply a fact. How else except by the word evolution can we designate the sequence of faunas and floras in precisely dated geological strata? And evolutionary change is also simply a fact owing to the changes in the content of gene pools from generation to generation.'
Commonly "fact" is used to refer to the observable changes in organisms' traits over generations while the word "theory" is reserved for the mechanisms that cause these changes:
- Paleontologist Stephen Jay Gould writes, 'Evolution is a theory. It is also a fact. And facts and theories are different things, not rungs in a hierarchy of increasing certainty. Facts are the world's data. Theories are structures of ideas that explain and interpret facts. Facts do not go away when scientists debate rival theories to explain them. Einstein's theory of gravitation replaced Newton's, but apples did not suspend themselves in mid-air, pending the outcome. And humans evolved from ape-like ancestors whether they did so by Darwin's proposed mechanism or by some other yet to be discovered.'
- Similarly, biologist Richard Lenski says 'Scientific understanding requires both facts and theories that can explain those facts in a coherent manner. Evolution, in this context, is both a fact and a theory. It is an incontrovertible fact that organisms have changed, or evolved, during the history of life on Earth. And biologists have identified and investigated mechanisms that can explain the major patterns of change.
Other commentators, focusing on the changes in species over generations and in some cases common ancestry have stressed that evolution is a fact to emphasize the weight of supporting evidence while denying it is helpful to use the term "theory":
- R. C. Lewontin wrote, 'It is time for students of the evolutionary process, especially those who have been misquoted and used by the creationists, to state clearly that evolution is a fact, not theory.'
- Douglas Futuyma writes in his Evolutionary Biology book 'The statement that organisms have descended with modifications from common ancestors--the historical reality of evolution--is not a theory. It is a fact, as fully as the fact of the earth's revolution about the sun.'
- Richard Dawkins says, 'One thing all real scientists agree upon is the fact of evolution itself. It is a fact that we are cousins of gorillas, kangaroos, starfish, and bacteria. Evolution is as much a fact as the heat of the sun. It is not a theory, and for pity’s sake, let’s stop confusing the philosophically naive by calling it so. Evolution is a fact.'
- Neil Campbell wrote in his 1990 biology textbook, 'Today, nearly all biologists acknowledge that evolution is a fact. The term theory is no longer appropriate except when referring to the various models that attempt to explain how life evolves... it is important to understand that the current questions about how life evolves in no way implies any disagreement over the fact of evolution.'
Predictive Power of EvolutionA central tenet in science is that a scientific theory is supposed to have predictive power, and verification of predictions are seen as an important and necessary support for the theory. The theory of evolution did provide such predictions. Three examples are:
- Genetic information must be transmitted in a molecular way that will be almost exact but permit slight changes. Since this prediction was made, biologists have discovered the existence of DNA, which has a mutation rate of roughly 10^-9 per nucleotide per cell division; this provides just such a mechanism.
- Some DNA sequences are shared by very different organisms. It has been predicted by the theory of evolution that the differences in such DNA sequences between two organisms should roughly resemble both the biological difference between them according to their anatomy and the time that had passed since these two organisms have separated in the course of evolution, as seen in fossil evidence. The rate of accumulating such changes should be low for some sequences, which code for critical RNA or proteins, and high for others - that code for less critical RNA or proteins; but for every specific sequence, the rate of change should be roughly constant through evolution. These results have been experimentally confirmed. Two examples are DNA sequences coding for rRNA which is highly conserved, and DNA sequences coding for fibrinopeptides (amino acid chains which are discarded during the formation of fibrin), which are highly non-conserved.
- Prior to 2004, paleontologists had found fossils of amphibians with necks, ears, and four legs, in rock no older than 365 million years old. In rocks more than 385 million years old they could only find fish, without these amphibian characteristics. Evolutionary theory predicted that an intermediate form between these two (i.e. a "fishibian") should be found in rock dated between 365 and 385 million years ago. In 2004, an expedition to islands in the Canadian arctic searching in rocks that were 375 million years old discovered fossils of Tiktaalik (a fish with tetrapod characteristics).
Common misconceptions about evolution- Biological evolution does not address the origin of life; for that, see abiogenesis. The two are commonly and mistakenly conflated. Evolution describes the changes in gene frequencies that occur in populations of living organisms over time, and thus, presupposes that life already exists. Evolution likewise says nothing about cosmology, the Big Bang, or the origins of the universe, galaxy, solar system, or Earth, although the term 'evolution' in the sense of a slow unfolding is used to describe such processes, e.g. Stellar Evolution, Cosmic Evolution.
- The word "theory" in "the theory of evolution" does not imply doubt in mainstream science regarding its validity; the words "theory" and "hypothesis" are not the same in a scientific context (see above). While "theory" in conventional usage tends to denote a "hunch" or conjecture, a scientific theory is a set of principles which, via logical induction, explains the observations in nature. The same inductive inferences can be made to predict observations before they are made. Evolution is a theory in the same sense as the theory of gravity or the theory of relativity.
- It is misleading to claim that evolution is completely random. Normally, the random results of genetic mutation are filtered by ontogeny, natural selection, and other non-random mechanisms. On the other hand, some evolutionary changes result from genetic drift, which is random.
- Humans did not evolve from monkeys or from any current non-human apes. Rather, humans and other modern simians—chimpanzees, gorillas, orangutans, baboons, etc.—all share a common early ancestor. It is believed that humans are more closely related to modern fellow apes than to monkeys, and humans and other apes share a later common ancestor that lived around 7 million years ago in the late Miocene epoch. However, fossil discoveries of "recently" (as in, only millions of years ago) extinct species are, in the experience of paleontologists, rarely direct ancestors of living species.
- The process of biological evolution is not necessarily slow. Millions of years are not necessarily required to see speciation (a change in characteristics of a kind of organism, typically rendering offspring infertile with the previous species). Indeed, it has been observed multiple times under both controlled laboratory conditions and in nature.
- Speciation does not happen within a single organism: a chimpanzee cannot be born a chimpanzee and turn into a different species within its lifetime. Evolution to a new species deals with changes to the gene pool of a population, which accumulate only over generations. Nor does speciation occur on an individual basis. It is not meaningful to speak of the first member of a new species.
- Organisms cannot pass on acquired traits to their offspring; a bodybuilder's children are not born with bigger muscles (but see epigenetics).
- A population can evolve to become simpler with less genetic information, and have a smaller genome—often called "devolution", but that is a misnomer.
- The theory of evolution does posit "transitional forms", but not "endpoint forms". That is, every animal, plant, fossil that exists, is an example of a transitional form. Evolution is a continuous process that has no "goal" per se.
- The claim that "almost all mutations are harmful" is false. In fact, most mutations have no noticeable effect, mainly because most mutations do not occur within coding or regulatory regions of the genome. One study gives the average number of mutations that arise in a human conception to be around 128, with an average number of harmful mutations per conception of 1.3. However, most mutations that have an effect on phenotype are indeed detrimental to the organism.
- The claim that evolution makes no meaningful predictions is not true—for example the discovery of the relationship between chromosome 2 and chimpanzee chromosomes at the end of the completion of the human and chimp genome projects was predicted, and makes meaningful sense as evidence of a common ancestor.
- The characterization of evolution as the "survival of the fittest" (in the sense of "only the fittest organisms will prevail", a view common in social Darwinism) is not consistent with the actual theory of evolution. Any organism which is capable of reproducing itself before dying is considered "fit". If the organism is able to do so on an ongoing basis, it will survive as a species. A more accurate characterization of evolution would be "survival of the fit enough".
Hopefully that's enough for you.
As for the "pink sky", again, you're the one using the word "abuse". What if the trusted figure who told the other man that the sky was pink sincerely believed that the sky was pink himself. He would not be abusing that trust, but simply passing on what he thought was best for the man to know. I think this more accurately parallels to the situations of those who don't believe in evolution.
Now, for the sake of you and I, and everyone else on this forum, and the internet itself (wouldn't want to clog it), let's please keep the replies shorter from now on.