What the HELL?!?! Why would you want to do that? The basic theory of evolution is effectively a scientific FACT!!! You start by putting your child up for adoption, you worthless piece of crap.
Evolution is a scientific theory that explains the origin of the diversity of species (note that it does not, and is not intended to explain the origin of life). The basic idea of evolution is that mutations result in genetic diversity in a population, and consequently different traits, and different selective pressures favor certain traits over others. In a diverse population, some individuals are better suited to the environment than others, and the individuals that are better suited are more likely to survive to reproduce and thus pass their genes on to the next generation. Consequently, the next generation will have more of the "good" genes and fewer of the "bad" genes than the generation before it. Because the environment is constantly changing, the definition of "good" and "bad" genes is also constantly changing. Something that used to be an advantage can become a disadvantage, and vice versa. More often, however, neutral traits will become either good or bad. Changes in environment can include not only changes in weather or resources, but also competition from other species.
As the environmental pressures change, the population of organisms changes with it. Over time, the little changes start to add up, and eventually the population will be so different from the ancestral state that it will be considered a different species. The diversity of species results from splitting of populations. If a population is separated by some geographical or reproductive barrier, the two subpopulations will likely evolve in different ways, to become two separate species. Eventually the two species may be reunited, but they will no longer be able to interbreed. Instead, they will compete with each other, and likely diverge even more.
The theory of evolution is supported by considerable scientific evidence, and is accepted by the vast majority of the scientific community. It is the ONLY scientific theory currently in existence that explains the diversity of species. Some people claim that "intelligent design" is an alternative theory for the origin of species. However, intelligent design is not a theory in the scientific sense. It is not supported by scientific evidence and can never be tested experimentally (not because we don't have the tools yet, but because it is theoretically impossible). Intelligent design provides an alternative to science, not an alternative scientific theory.
Science is not about finding a single piece of evidence to conclusively prove a theory. It's about constructing theories to fit the existing evidence and gathering new evidence that supports or refutes existing theories. Evolution is supported by a preponderance of evidence. While no one point conclusively proves it, when all the evidence is considered in the context of existing scientific knowledge evolution is a well substantiated theory. Intelligent design is not. What follows are brief explanations of some of the evidence that supports the theory of evolution.
1. Vestigial structures
One example of a vestigial structure in humans is the appendix. It has no function. Removing it is harmful only in so far as any surgery is associated with certain risks (so I wouldn't have it removed just for fun, but it's because of the surgery not the absence of the appendix). An appendix is found in several mammals. In humans it is small and has no known function. In rabbits and many other herbivores it is large and is used in the digestion of cellulose.
Another example of a vestigial structure is the hipbones of snakes. Snakes evolved from quadrupeds, and some species still retain not on pelvises, but tiny protrusions of bone in a location that corresponds to the location of the legs in other quadrupeds.
2. Microevolution can be observed in both a controlled laboratory setting and in nature.
Creationists will tell you that microevolution does not prove macroevolution. This is true. However, it does provide evidence that macroevolution may be possible. Taken in the context of the other evidence for evolution, microevolution provides a mechanism by which macroevolution could occur. On its own, it doesn't prove that macroevolution occurs, but it does suggest that it is possible.
3. The fossil record.
Although the fossil record does not provide a “complete” record as fossils form only under certain conditions, it does show a gradual change in the morphology of species as well as numerous extinct species. There are a number of methods used to date fossils, and the time period from which a fossil comes can be determined with reasonable accuracy.
4. Imperfect structures (the blind spot of the mammalian eye, for example).
I want to mention the bind-spot of the mammalian eye specifically because creationists often hold up the human eye up as an example of something that is too perfect to occur by "chance" (i.e. as the result of the natural selection of beneficial changes among random mutations).
There are also numerous examples where the morphology of a species is constrained by similar patterns in its ancestors (quadrupeds, vertebrates, etc.).
5. Developmental biology reflects evolutionary lineage.
Creationists like to bring up a man named Haeckel in response to this argument. Haeckel suggested that development reflects evolutionary origin. It was later discovered that several of the sketches he used as evidence over-exaggerated certain features, and some were of different embryos all together. However, many of his sketches do accurately reflect the morphology of the embryo. Haeckel's methods were sometimes wrong and his ethics were poor, but it just so happens that his theory turned out to be fairly accurate.
Any developmental biologist can tell you that embryos of related species show similar morphology in the early stages of development. The point at which their development begins to diverge shows a strong correlation with the relative point at which the evolution of the two species diverged. Human embryos look similar to chimpanzee embryos for a lot longer than they look similar to cat embryos, but all three develop similar structures in the early stages of development. The early embryos of humans, chimps, and cats are similar to each other but quite different from, say, a sea urchin embryo. This is based on photographs of actual embryos taken by respectable scientists, NOT on Haeckel's drawings.
I find it rather funny that creationists try to argue that because one scientist was a fraud we should disregard all of developmental biology.
6. Genetic analysis shows similarities among species reflecting evolutionary origins.
The main point here is that recent work has shown that the extent of genetic divergence among species is consistent with the expected separation based on the fossil record and morphological evidence. This supports the conclusions drawn from the other evidence.
Genetic analysis often reveals remnants of a gene that is functional in one species but not another (i.e. a mutation occurred that made the gene non-functional, but most of the sequence is still intact). Why would God have created non-functional sequences that are extremely similar to functional genes found in related species?
Also, non-coding regions of DNA show degrees of similarity that are consistent with the expected degree of evolutionary divergence. I understand how you could argue that God was essentially working form a common genetic template for all species, but why change the non-coding regions? These differences result from mutations that do not affect the phenotype of the species in any way but accumulate over time. Non-coding regions show sequences that are conserved with changes, and the number of changes is consistent with the number of mutations that would be expected to have occurred since the approximate time of existence of most recent common ancestor.
7. Homologous structures.
Homologous structures are structures that typically have similar morphological features and, often, similar functions, and are the result of evolutionary change of a single structure present in the most recent common ancestor of the two species. A homoplastic structure is one that may have a similar function and superficial appearance to another structure but is the result of convergent evolution (i.e. it was not present in the most recent common ancestry).
The most obvious examples of homoplastic structures are things like a human's hand and a gorilla's hand. A more subtle example is the human hand and the bat wing. Although the two structures clearly serve different functions, their bone structures are nearly identical. This is because the bat wing is a modified mammalian forelimb. In other word, the most recent common ancestor of the human and the bat was a mammal that had a forelimb with a bone structure similar to that of the modern human hand and other mammalian forelimbs. In humans this forelimb became the hand. In bats it became the wing.
An interesting example of homoplastic structures is the bird wing and the bat wing. Although the two structures clearly serve similar functions (i.e. flying), they are anatomically quite different. They have quite different bone structures and operate according to different mechanical mechanisms. In fact, the bat wing is structurally more similar to human hand than the bird wing. Incidentally, the bird and bat wings are homoplastic as wings but homologous as forelimbs.
That is just one example. The animal kingdom is littered with examples of structures that serve different functions but have extremely similar morphological traits, and structures that serve similar functions but show clear evidence of distinct evolutionary origin.
8. Many cellular and biochemical processes are conserved in a variety of species.
The point here is that virtually all cells utilize similar mechanisms of DNA replication and protein synthesis, share certain respiration pathways, and other biochemical processes. Related species show more similarities. For example, all plants are capable of photosynthesis, and utilize a virtually identical biochemical pathway to accomplish this. If you study cell biology you will find numerous examples of pathways that are common to different types of cells. I'm not going to go into this more here as it requires considerable background in cell biology. However, these biochemical similarities support they theory that all cells share a common ancestor.
9. Vestigial biochemical pathways (for example, pancreatic cells are light-sensitive even though they are located deep inside the body).
These are similar to vestigial structures at the cellular level. The specific example I mentioned is the light-sensitive behavior of pancreatic cells. Basically, the pancreas is located inside the body and will never be exposed to light. However, pancreatic cells grown in vitro (i.e. in a Petri dish, test tube, etc.) demonstrate light-sensitive activation of biochemical pathways similar to that seen in the cells that form the retina. There is no reason for this behavior unless this pathway is a remnant (i.e. a vestigial pathway) of a pathway present in an ancestral cell that did have come in contact with light.
There are many other examples of vestigial biochemical pathways. Like vestigial structures, their existence is easily explained by evolution but makes no sense in the context of creationism or "intelligent design."
For more information, see the following links:
http://www.txtwriter.com/backgrounders/Evolution/EVpage16.html
http://evolution.berkeley.edu/evosite/lines/index.shtml
http://fermat.nap.edu/html/creationism/evidence.html
Or just do a google search for something like “evidence of evolution,” or check your local library.
People have trouble accepting evolution for the same reason they had trouble accepting that the Earth was not flat and was not the center of the universe. The funniest thing is when people claim that creationism has been proven or is fact. It's a fact just like it is a fact that the world is flat. It looks that way so it must be true. Since we can't see evolution it must not exist. I also find it amusing that people think that it makes more sense that women were created from a man's rib than that we are the result of evolution.
I've noticed that many people don't understand the theory of evolution, and essentially use that as a basis to attack it. For example, many people will point out that evolution does not explain the origin of the first cells or where matter came from. No duh it doesn't. It's not supposed to. Evolution explains the origin of the diversity of species, not the origin of life. There are other theories that address that issue, and I don't think any of those are accepted as fact. I do, however, think it's a fair bet that life does in fact exist, so it's perfectly valid to construct a theory that presupposes that life exists.
People also misunderstand the concept of a scientific theory. What they fail to realize is that most of science is made up of theories, and while many of these theories have been effectively proven true, they're still called theories. Unlike the common English use of theory, in science a theory is an explanation of facts, which is subjected to rigorous scientific testing. Evolution is called a theory not so much because we're not sure if the basic concepts are accurate, but because we are not confident that every single little detail is perfectly accurate. There may be complexities and details that are not yet fully understood, but the basic idea that species evolve and that the process of evolution has resulted in the diversity of life we see today is basically an established fact.
Another problem that may be partly to blame for the confusion regarding evolution is the presentation of "scientific evidence" by creationists that the claim contradicts the theory of evolution. I often see misleading and incorrect use of scientific data to "disprove" evolution. For example, on prominent creationist website cites a study John A. Eddy and Aram A. Boomazian which they claim says that the sun has been contracting for 400 years when, in fact, the study examined evidence from under 100 years and extrapolated the rest from a single report of the appearance of a solar eclipse in the 1500s. Furthermore, the study was conducted about 50 years ago, and dozens of studies since then have found that the data was based on flawed methodology and the sun is actually not contracting.
Here's that site: http://www.khouse.org/articles/2002/418/
And some background on the study they cited: http://www.asa3.org/ASA/PSCF/1986/PSCF9-86VanTill.html
The problem is that people read that and believe that evolution has been disprove. I saw someone quote that particular website here on Answers as scientific proof that the theory of evolution was false. The people who wrote the creationist article probably did their research and latched on to the one study that supported their theory, but the people who read it don't know that it is an outdated study, that the conclusion is overinflated (the 400 year thing), or that it contradicts the findings of dozens of more recent and more accurate studies.
Apparently the phenomenon of distorting scientific data to further a creationist agenda is fairly widespread. One of my bio profs talked about a particularly egregious example of someone (I don't remember his name) who actually obtained a PhD in evolutionary biology for the expressed purpose of disproving the theory of evolution, and now goes around writing articles that pretty transparent to scientists but are just believable enough to confuse the general public.