- A fact is an objective observation that does not attempt explanation, a hypothesis proposes an explanation that requires testing, and a theory is an explanation that has been extensively tested and supported by evidence. - Natural selection is a scientific theory and not a fact or hypothesis because it provides an explanatory framework for observations that has been rigorously tested and supported over time. - The key difference is that facts present objective observations, hypotheses propose explanations, and theories have withstood significant scrutiny and amassed supporting evidence.

1. Facts, Theories, and Hypothesis Are they the same thing? Natural Selection is which one?

2. Scientific Fact Webster’s online dictionary defines a fact as “a piece of information presented as having objective reality” It is true universally It does NOT try to give an explanation of an observation, but is the objective observation of a phenomenon

3. Examples of scientific facts Air pressure at sea level 14.7 psi The moon orbits the earth Plants create food by the process of photosynthesis

4. Hypothesis Webster’s online dictionary states a hypothesis is “a tentative assumption made in order to draw out and test its logical or empirical consequences” A hypothesis attempts to explain a phenomenon, but still needs to be tested

5. Example of hypothesis Observation: ground water is contaminated Hypothesis: There is a leak in an underwater container holding gasoline. This possible explanation can be tested Examine the container to see if there is a leak Examine the water to see if it contains the same type of gasoline held in the container If the evidence supports the hypothesis, it is on its way to becoming a theory.

6. Scientific Theories According to Webster’s online dictionary a theory is “a plausible or scientifically acceptable general principle or body of principles offered to explain phenomena” It is a hypothesis that has been tested, reviewed, and supported by many scientists under different circumstances It tries to explain or interpret an observation It is NOT proven, but supported

7. Examples of scientific theories Gravitation Theory All objects with mass attract each other Einstein’s General Theory of Relativity would view gravity as the geometry of space and time, showing that neither theory can be considered fact as there are two very reasonable explanations for why objects behave the way they do when they fall Germ Theory Microorganisms cause disease There are exceptions to this idea, but for the most part evidence supports this idea, making it theory

8. Natural Selection is… Natural Selection is NOT a fact because it is an explanation/interpretation of observations, not the actual universal reality Natural Selection is NOT a HYPOTHESIS because it has been overwhelmingly tested and supported, making it a THEORY.

9. Conclusion Facts, theories, and hypothesis are NOT the same thing Natural Selection is a scientific theory, since it has been tested, reviewed and supported by an abundance of evidence compiled from many scientists in many fields.