Home ] Up ] [ Notes 1: What is Science ] Notes 2: Intro to Evolution ] Notes 3: Pre-Dinosaur Reptiles ] Carnosaurs ] Sauropodomorphs ] Sauropods ] Ornithopods ] Thyreophora ] Marginocephalia ] Nasal Turbinates and Hot Blooded Dinos ] Isotopes and Hot Blooded Dinos ]

Up

 

What is Science?

Gel 113 is a Science course, and most students take it to fulfill a science requirement in the General Education Program. So what exactly is it that sets this course apart from non-science courses? In Gel 113 you will learn facts about dinosaurs; but don't you learn facts in a History course, or a Social Science course? Of course you do. So what's the difference?

The difference is that the facts and/or procedures you learn in a Science course are based on the fundamental philosophy or technique of Science which is known as the Scientific Method. The Scientific Method is based upon the idea that careful observation of natural phenomena can lead to suggested explanations for those phenomena (hypotheses), and that these explanations can then be tested to determine whether they are correct. The "tests" themselves must be carefully described so that other scientists who are interested in the phenomena being studied can repeat the "tests" and judge the results for themselves. If repeated tests always yield the same results, the "explanation" is considered to be a "fact" and ends up in a course like GEL 113. Consider the following example.

What causes rain?

Two people are asked to investigate this question. What observations can they make? Both make the simple observation that rain is water which comes from the sky. Person 1 immediately hypothesizes that rain is caused by angels crying (Hypothesis 1). Person 2 makes some other observations: 1) air contains a certain amount of moisture (she's tried to eat a salty pretzel in New York City on a humid day and watched the salt turn into a saline solution on the pretzel), and 2) air gets colder the higher up you go (she's climbed a mountain). Based on these two additional observations person 2 hypothesizes that moist air rises upward and cools, which causes the water vapor to condense into drops, i.e., rain (hypothesis 2).

Now what?

Scientific method requires that these hypotheses be tested. Person 1 is in a bind. He can try to fly around in a rain storm and look for angels, or simply admit that his hypothesis is NON-TESTABLE, and therefore NOT scientific. (Scientific Method requires TESTABILITY). Person 2, on the other hand, can perform a simple test. She can take a piece of glass and put it into a dry freezer to make it very cold. On a humid day she can take it out and see if water condenses on the glass (since the environment in the freezer is dry any moisture which appears would have to come from the air). She can also run a simple experiment in the Spring or Fall to determine if dew comes from the air (this will probably require staying up all night). The point is that she or some other person can repeat this test (or similar tests) over and over and always come to the same conclusions. Her hypothesis will now be considered fact.

 

 

Types of Logic in Science.

There are two types of logic used in science: Induction and Deduction.

Induction is the type of logic through which a person draws a conclusion from particular facts or individual observations. In the rain example, person 2 demonstrated Induction by using her observations to formulate her hypothesis.

Deduction is the use of known principles to formulate a hypothesis. If person 2 had simply stated that it is well known that water vapor condenses to liquid water when cooled, and that rain is probably caused by the cooling of moist air, she would have been using deductive reasoning. Note that, based upon a known principle she would have been predicting a result.

A classic example of deductive logic is presented by Mr. Spock (how can you possibly discuss Logic and not mention Mr. Spock?) in the original Star Trek episode "Court Martial". In it Spock states: "If I release a hammer on a positive gravity planet, I do not have to watch it to know that it will fall." Note that he uses a given principle (gravity) to make a prediction (the hammer will fall down).

Lastly, the rain example also illustrates the rule that scientists follow which simply states that you always look for the simplest answer. This rule is given various names including Occam's Razor and the Principle of Parsimony. Note that hypothesis 1 requires spiritual intervention in a natural process, while hypothesis 2 required no supernatural occurrence, only simple natural phenomena. In general, any hypothesis which requires Divine intervention, Little Green Men, the Loch Ness Monster, or Elvis in order to explain a phenomenon usually fails the simplicity test.

 

 

Dinosaurs

All right, how does all this apply to dinosaurs?

All of our knowledge about dinosaurs has come through this process.

We all known the Tyrannosaurus rex ate meat, right? Have you ever seen a T. rex eating? (Other than in the movies, of course!). Unless you happen to have a time machine at home I rather doubt that you have. Then again neither has anyone else. So how do we know what it ate? We look at its teeth.

All modern meat eating animals have sharp, fang-like teeth (look at a cat or dog). We test this hypothesis directly on modern (live) animals through direct observation. Based on those observations we derive a principle, also known as a Model (sharp teeth = meat eater). We then base a prediction on this principle. All meat eaters will have sharp teeth, T. rex has sharp teeth, therefore T. rex was a meat eater. We have determined the dinosaurs dietary habits based on deductive reasoning.

However, there is a fly in the ointment! What we have just completed is an exercise in Observational Science, not Experimental Science. In either case, we construct a model based upon previously determined principles, but in Experimental Science we can conduct a direct test or experiment to verify our hypothesis (remember the rain example). In observational science we cannot experimentally test our hypothesis, instead we compare observations to what we expect (i.e., our predictions). As more and more observations are made which support our hypothesis, the probability that we are wrong becomes less and less, but since no direct experiment is possible, there is always the possibility (albeit small) that we may be wrong.

 

 

Facts, Interpretations and Conclusions in Dinosaur (Observational) Science

The following is a guide to the four levels of ?fact? often presented about dinosaurs in the media.

 

Level 1. Inevitable Conclusions. In these cases there are no possible alternatives. Example: dinosaurs are reptiles. Since dinosaurs meet every criterion in the definition of reptile based on the study of modern reptiles there are no alternatives to the conclusion that they are reptiles.

Level 2. Likely Interpretations. While a large body of evidence supports these interpretations, there are alternatives which, to date, have not been proven wrong. Example: T. rex was a carnivore. There are some paleontologists who argue that T. rex was too big and slow to be a successful predator (carnivore); but, instead was a scavenger (like a big vulture). At present there is no conclusive evidence to prove either interpretation.

Level 3. Speculative. May be right, and are testable through observations, but at present lacks any real supportive evidence. Example: Velociraptor hunted in packs. This hypothesis would be supported by a trackway showing numerous individuals following a prey dinosaur, or by a mass death assemblage containing only Velociraptor bones. To date neither has been found.

Level 4. Reasonable. Plausible explanations which are completely untestable. Example: color patterns on dinosaurs. Since skin impressions are extremely rare, and skin colors are never preserved in the fossil record, there is no way to test the hypothesis that T. rex was a pastel pink or that Velociraptor had racing stripes.

 

  Return To Dino Notes.