It is a theory in biology exactly the same way gravitation is a theory in physics. In the field of science, we use terms in more specific ways than those same terms are used colloquially. A theory, strictly speaking, is a set of laws that govern the natural world, that have been modeled by a body of knowledge within one or more disciplines, and that has been tested using the scientific method numerous times without being refuted. Evolution is the model that describes how different traits are affected over several generations of offspring, through inheritance and through interactions with the environment. To say that one does not believe in evolution, strictly speaking, is to say that one does not believe in the body of scientific knowledge that models how traits are inherited and selected for fitness by the environment over several generations. Colloquially, I think, when people say "I don't believe in evolution," it really means that those people don't believe in the concept of "abiogenesis," i.e. the singular idea that, at some point in time, life came about from something that was not alive, which is actually an entirely different concept.

The University of California, Berkley, defines a theory as "a broad, natural explanation for a wide range of phenomena. Theories are concise, coherent, systematic, predictive, and broadly applicable, often integrating and generalizing many hypotheses." Any scientific theory must be based on a careful and rational examination of the facts. Facts and theories are two different things. In the scientific method, there is a clear distinction between facts, which can be observed and/or measured, and theories, which are scientists' explanations and interpretations of the facts. An important part of scientific theory includes statements that have observational consequences. A good theory, like Newton's theory of gravity, has unity, which means it consists of a limited number of problem-solving strategies that can be applied to a wide range of scientific circumstances. Another feature of a good theory is that it formed from a number of hypotheses that can be tested independently. The evolution of a scientific theory A scientific theory is not the end result of the scientific method; theories can be proven or rejected, just like hypotheses. Theories can be improved or modified as more information is gathered so that the accuracy of the prediction becomes greater over time. Theories are foundations for furthering scientific knowledge and for putting the information gathered to practical use. Scientists use theories to develop inventions or find a cure for a disease. Some think that theories become laws, but theories and laws have separate and distinct roles in the scientific method. A law is a description of an observed phenomenon in the natural world that hold true every time it is tested. It doesn't explain why something is true; it just states that it is true. A theory, on the other hand, explains observations that are gathered during the scientific process. So, while law and theory are part of the scientific process, they are two very different aspects, according to the National Science Teachers Association. A good example of the difference between a theory and a law is the case of Gregor Mendel. In his research, Mendel discovered that two separate genetic traits would appear independently of each other in different offspring. "Yet Mendel knew nothing of DNA or chromosomes. It wasn't until a century later that scientists discovered DNA and chromosomes ? the biochemical explanation of Mendel's laws," said Peter Coppinger, an associate professor of biology and biomedical engineering at the Rose-Hulman Institute of Technology. "It was only then that scientists, such as T.H. Morgan working with fruit flies, explained the Law of Independent Assortment using the theory of chromosomal inheritance. Still today, this is the universally accepted explanation (theory) for Mendel's Law."

"To say that one does not believe in evolution,..." No one here said that but you. And I was trying to explain on a simple level she could understand. Adding a bunch of techno babble isn't going to help if she doesn't understand the basics. I also didn't bring up all the other elements involved in evolution for the same reason. Besides the fact this is in the religion category not biology.

"'To say that one does not believe in evolution,...' No one here said that but you." Did I use quotes? The OP strongly implies that he or she doesn't believe in evolution in the description. Do you disagree? If not, then why try to refute that particular infinitive phrase? This OP doesn't seem to have come here to get answers, just to obtain affirmation of his or her own worldview, so no answer is going to sway that, regardless of how much or how little "technobabble" (words like "offspring" and "inheritance," I guess) is used. I'm glad we agree that hypothesis, theories, facts, and laws are different things. But, when you say "The evolution of a scientific theory A scientific theory is not the end result of the scientific method; theories can be proven or rejected, just like hypotheses," I think there is a little bit of misunderstanding applied. The scientific method is the primary way scientists control how they test the natural world. From those tests come, eventually, theories. It is true that scientific theories have been replaced in the past, but I don't think it works the way you seem to be alluding to. Again, the distinction between a scientific theory, such as the theory of evolution, and the scientific hypothesis, such as the Lamarckian Hypothesis. Where Lamarck came up with two trends he proposed, saying he thought this and he thought that, based off of conjecture, there was no experimental confirmation attempted until decades later. Medel's Laws, on the other hand, we based off of experimental data. Both were considered quackery at the time of contemporary publication, but their approaches were very different. And just because Mendel did not mention DNA doesn't mean that DNA replaced Mendel's laws. On the contrary, what we know about DNA goes hand in hand with our understanding of genetic inheritance. As for categories, you and I both know that the question rarely fits the category. "What is Evolution" isn't a religious question, since neither the Torah, Quran, Vedas, nor the Bible have anything to say about it, seeing as how those scriptures all predate the conception of "evolution."

Oh really? Tell me all about porcine heart valve xenotransplantation ... (*crickets chirping*) You're way out of your depth here. Pick up a text book. Read it. Come back afterward, and maybe we can have a meaningful discussion then, but, for now, I have to disagree with everything you said in your answer, simply because you have no idea what you are talking about. You obviously don't understand the meanings of the words "theory," "outside," "influence," "man," "monkey," "genus," or, especially "intelligent."

Anyone can ' knock' a comment...so WHAT are your ideas on the question? Show me an example of something improving without outside influence. In my book, Jehovah god is the influence. And his book does not support evolution... One ' type' does not change into another 'type'.

Again, your "answer" to this question shows a high degree of ignorance. 1. Evolution is not a theory that things change without outside influence, it is the scientific theory of how generations of life forms change over a long term, based on random mutations and selection of genes due to mate selection and survival. 2. No one is trying to tell you that "present man got better from monkeys." Homo sapiens are apes, like chimpanzees and gorillas, because we are bipedal mammals with large crania, opposable thumbs, and lack tails, among hundreds of other traits. 3. Intelligent man did not begin with Adam and Eve. It's a story. The Bible itself isn't even consistent with its own story between Genesis 1 and Genesis 2, reinforcing the idea that it was never intended to be interpreted literally. 4. Man-like life before recorded history is not classified as "the genus of monkey." Monkeys and apes came from a common ancestor. 5. Monkeys are not a genus. They are a infraorder containing two families, which each contain several genus. 6. Your argument that we can accept heart valves from pigs proves that we did not evolve from an ancestor common with monkeys is full of logical fallacies, including argument from ignorance, strawman, post-hoc-ergo-propter-hoc, and non sequitor.

Same as any other idea that goes beyond instinct.