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| Dallas Zoological Society Partnership : Zoo Science Scientific Inquiry |
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Topic Overview
Quick Facts
Historically, the scientific method is traced to
Alhazen, a medieval Muslim scientist from Basra,
Iraq who
emphasized gathering information through experiment in his Book of Optics.
An example of a seven step scientific method is:
1) state the problem, 2) research the problem, 3) state the hypothesis, 4) test
the hypothesis, 5) analyze the results, 6) state the conclusion, and 7) repeat
the work.
Engineers often use a different set of steps
than scientists. One example is as follows: 1) define the need, 2) establish
design criteria, 3) do background research of what has already been done, 4)
prepare preliminary designs and material lists, 5) build and test a prototype,
6) retest and redesign, 7) present results.
Nobel physics laureate P.W. Bridgman once said,
“It seems to me that there is a good deal of ballyhoo about scientific method.
I venture to think that the people who talk most about it are the people who do
least about it…Scientific method is something talked about my people standing
on the outside and wondering how the scientist manages to do it…In short,
science is what scientists do, and there are as many scientific methods as
there are individual scientists.”
Pictures of dinosaurs in the media are
constructed from a combination of scientific theory and filling in the gaps
with artistic imagination.
Aristotle supposedly provided long arguments as
to why men and women had different numbers of teeth, without bothering to
verify his assumption.
A scientific law describes how something works.
A scientific theory describes why something works.
Popular Science magazine selected the “10 worst
jobs in science.” Number two involved some incredibly skilled observers – those
who inspect the 1.5 billion tons of manure produced by livestock each year in
order to learn about how to eliminate the bacteria E. coli from our food
supply.
It is estimated that 50-100 million animals are
used worldwide for experiment (including a large number of fruit flies and
mice). Most of these animals are either killed during the experiment or
subsequently euthanized.
Approximately 30 years ago, Viking 1 sent back
images from Mars that looked remarkably like there was a giant face of a man on
the Martian surface. Theories of alien civilizations filled the popular press.
NASA was also seduced by this pseudoscience, as the “Face on Mars” became a
priority for Mars Global Surveyor 1997. A scheduled flight over the region
proved that the image it was just a landform and not an alien artifact.
Begin the Lesson
What is science? Attempts to answer this question throughout
the centuries have identified traits common to all scientific research:
observation, hypothesis, and experiment. These components are often presented
in step-by-step recipes and referred to as The
Scientific Method. Although practical scientific research rarely follows
the scientific method explicitly, the steps in this method provide
non-scientists with a philosophical understanding of the path to scientific
theory. The method also helps scientists establish protocol for experiments and
share data and results to a wide audience. The main challenge is developing an
appreciation for inductive as opposed to deductive reasoning, where general
theories form from specific observations. Other characteristics such as
falsifiable hypotheses, repeatability of observation, and experimental control
serve as tests for scientific validity.
Whole Class Introduction to the Lesson
You will need at least one computer with Internet connectivity
and a projection device, a classroom with more than one computer, or access to
a computer lab. This introduction will take approximately 10 minutes to
complete.
Use optical illusions to introduce the differences between
human perception and reality and how scientific analysis can help us determine
what is true. Optical illusions highlight the challenges of measurement and
observation. The sites:
http://www.indiana.edu/~ensiweb/lessons/percep.html, http://www.eyetricks.com, and http://www.niehs.nih.gov/kids/illusion/illusions.htm provide visual examples to present to the class. Sample Questions:
What do you see in the picture?
How would you determine if your observations are
true?
Why do you think your eyes see something
different that reality?
What do your experiences with optical illusions
tell you about relying solely on your senses for observation?
Can two different observers arrive at different
conclusions?
How can scientific methods ensure that your
observations match reality?
As part of the introduction, you may want to review some of the
glossary terms in advance of students going online. At this point you can
launch the WebLesson as whole-class activity using a projection device, or you
can assign students to work individually or in teams in a computer lab.
WebLesson Sites
Introduction How do scientists discover anything new? What makes knowledge scientific? There are many paths leading to scientific discovery, including relentless systematic work, mistakes, luck, and chance. Textbooks and philosophers of science often present a recipe for scientific research known as the scientific method.
Authors present the scientific method in many forms, varying in the order and number of steps. However, all forms use observation, hypothesis, and experimentation to arrive at a final theory. Observations must be capable of being repeated by different observers at different times. Hypotheses must be falsifiable. That is, if a hypothesis is false, there must be a way to show it. Experiments must be repeatable as well as have scientific control, a baseline against which to compare test results. Theories must be robust, holding up to criticism and to challenge, yet open to change. There is a current trend to de-emphasize the use of the scientific method when teaching science, primarily because real scientific discoveries rarely result from strictly following this method. Indeed, some contemporary scientists decry the existence of the scientific method, feeling that it improperly describes the process of scientific inquiry. Others find it indispensable in teaching students the scientific reasoning necessary for designing experiments. Scenario Imagine that you are designing a habitat for a new animal at the zoo. Your task is to create an environment that provides the animal with a means of obtaining food, water, shelter, social interaction, and entertainment similar to the wild. In order to create the exhibit, you will need to use elements of the scientific method. You will have to observe the animal in the wild, hypothesize animal behavior, experiment with a variety of surroundings and diets in captivity, and come up with consistent theories of animal behavior.
Lesson Pages
Wild Animal Park Exhibit: African Elephant
http://www.sandiegozoo.org/wap/ex_elephants.html Rich Media
The Skeptics vs. the Ozone Hole
http://www.wunderground.com/education/ozone_skeptics.asp
Oregon Zoo – Gallery: ZooLights 2006 video
http://www.oregonzoo.org/VideoArchive/FlyingReindeer.htm Rich Media
The T. W. I. N. K. I. E. S. Project
http://www.twinkiesproject.com/ Conclusion & Project
Conclusion The scientific method gives us a way to understand how science differs from other subjects. Science is unique in that it begins with observation and continues by identifying patterns, making educated guesses, and experimenting in order to arrive at theories for how nature behaves. Science is not concerned with the meaning of life and the universe, as are philosophy and religion. Science is not meant to challenge our worldview by creating illusions and paradox, as are literature and art. Science deliberately avoids being human-centered, a vital focus of history. The scientific method provides a way to organize scientific knowledge, reserving a place for science within the complex realm of our physical and spiritual existence.
Project You have been asked to create an exhibit for a new resident at the zoo: an alien from Mars. Create a list of questions to guide a team of scientists in deciding how to set up the exhibit. Include questions that lead the group through important observations aimed at determining diet, social interaction, and physical needs. Use the questions to create guidelines for developing hypotheses and experimental tests concerning the behavior of the alien. Pay attention as well to proper protocol for animal research. In all of your questions, emphasize the procedures of the scientific method.
Glossary
observation - impressions of the physical universe that come to us directly through our senses or indirectly through instruments
inquiry-based education - type of learning where students learn by questioning, with the teachers becoming facilitators of learning rather than vessels of knowledge
scientific principle (law) - description of how something behaves
scientific theory - stablished and experimentally verified fact or collection of facts about the world. Unlike the everyday use of the word theory, it is not an unproved idea, or just some theoretical speculation
hypothesis - proposed explanation for an observation, phenomenon, or scientific problem
experiment - test to examine the validity of a hypothesis
fact - observation that has been repeatedly confirmed that is believed to be true or real
conclusion - decision based on a set of observations and facts
theory - explanation that incorporates facts, laws, inferences, and tested hypotheses
deductive reasoning - going from a general theory to specific examples
inductive reasoning - using specific examples from observation and experiment to arrive at a general theory
falsifiable hypothesis - hypothesis that can be tested for falsehood
controlled experiment - situation where two virtually identical experiments are conducted, one of which is a control, where the factor being tested is not applied
experimental variable - factor that is tested in an experiment
scientific paradigm - collection of theories that are accepted by most of the scientific community
Occam’s Razor (the Principle of Parsimony) - principle that the best theory is the simplest, the one requiring the least number of suggestions
fantasy - fictional description that includes magic, myth, and supernatural elements
supernatural - transcending the laws of nature
mathematical model - abstract model that uses mathematical language to describe a system
pseudoscience - any body of knowledge that claims to be scientific but does not follow the basic components of the scientific method
test subject - person, animal, or thing put in experimental conditions
control subject - person, animal, or thing in normal non-experimental conditions
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