1. Body Of Knowledge - Nature of Science
Scientific Thinking
Body Of Knowledge - Nature of Science
Big Idea 1 – The Practice of Science
Big Idea 2 – The Characteristics of Scientific Knowledge
Big Idea 3 – The Role of Theories, Laws, Hypotheses, and Models

2. SC.8.N.2.2 – Discuss what characterizes science and its methods
Science is a way of understanding the natural world around us.
It is based upon the idea that our senses, and extensions of our senses through instrumentation/technology, give us accurate information about the natural world.
Scientists ask, “What is there? How does it work? How did it come to be this way?

3. The joy of science is in the freedom to explore and wonder
Science relies on evidence and creativity

4. Science explanations are evaluated by testing and using evidence
Science explanations are evaluated by testing and using evidence. Explanations that don’t fit evidence are rejected or modified and tested again.
Science claims are subject to peer review and replication. Scientists attempt to identify alternate explanations to get closest to the truth.

5. There is NO one “Scientific Method”!
Scientists continually make observations, question, and form multiple hypotheses.
Science never “proves.” Hypotheses are either “supported”
or “not supported” by the data collected.

6. SC.6.N.1.5 – Recognize that science involves creativity, not just in designing experiments, but also in creating explanations that fit evidence
Dinosaur Extinction Hypotheses:
Asteroid?
Volcanism?
Climate Change?

7. SC.8.N.1.5 – Analyze the methods used to develop a scientific explanation as seen in different fields of science
Physicists
Biologist
Volcanologist
Geologists
Chemists

8. SC.7.N.1.6 – Explain that empirical evidence is the cumulative body of observations of a natural phenomenon (event) on which scientific explanations are based

9. SC.7.N.1.7 – Explain that scientific knowledge is the result of a great deal of debate and confirmation within the science community
Science Conferences

10. SC.8.N.1.6 – Understand that scientific investigations involve the collection of relevant empirical evidence, the use of logical reasoning, and the application of imagination in devising hypotheses, predictions, explanations, and models to make sense of collected evidence

11. SC.6.N.3.1 – Recognize and explain that a scientific theory is a well supported and widely accepted explanation of nature and is not simply a claim posed by an individual.
The Theory of Plate Tectonics
Evidence – Sea Floor Spreading, Distribution of earthquakes and volcanoes, Fossils
Claim – Volcanoes erupt in Hawaii because of Pele, the goddess of fire

12. SC.6.N.3.2 – Recognize and explain that a scientific law is a description of a specific relationship under given conditions in the natural world (different from societal laws).
Newton’s Laws of Motion

13. SC.6.N.3.3 – Give several examples of scientific laws
Law of Conservation of Energy
Newton’s Laws of Motion
Universal Law
of Gravitation
Law of Conservation of Mass

14. SC.7.N.3.1 – Recognize and explain the difference between theories and laws and give several examples of scientific theories and the evidence that supports them
THEORY
Explanation based upon
evidence
Verified multiple times
Can be used to make
predictions
LAW
A statement that describes an action or
set of actions
Can be expressed as a mathematical
equation
Simple, true, universal
Theories explain WHY
something happens
Laws describe WHAT happens

15. Theory Example – The Theory of Biological Evolution
All life on Earth shares a common ancestor. There is “decent with modification.”
Evidence – Fossil Record, Genetic Studies, Radiometric Dating, Stratigraphy
The horse’s foot adapted to a changing climate

16. SC.6.N.3.4 – Identify the role of models.
Model – a representation of an object, process, system, or event that is
similar to the original object or idea
role – models help scientists better understand objects/ideas; allow
hands-on contact with matter that is too small, too large, too far
away, too dangerous, or too expensive to build

17. SC.7.N.3.2 – Identify the benefits and limitations of the use of scientific models
Used to study matter that is too large,
too small, too far away, too dangerous,
or too expensive to study directly
Models can be physical, mathematical,
computer simulations, or conceptual
Can be used to make predictions
Limitations
May lack details
May not be composed of the original
material (model of the Sun)
May not be able to demonstrate every
aspect of the system

18. SC.6.N.2.2 – Explain that scientific knowledge is durable because it is open to change as new evidence or interpretations are encountered SC.8.N.3.2 – Explain why theories may be modified but are rarely discarded
Germ Theory (1870s) – specific microorganisms are the causes of specific diseases
Louis Pasteur
demonstrated that
microbes decomposed
meat and heat kills
bacteria
Robert Koch
specific diseases were
caused by specific germs
Miasma - Before the 1800s, it was thought that diseases were caused by miasma, a poisonous vapor in the air filled with particles of decaying matter!

19. SC.7.N.1.2 – Differentiate replication (by others) from repetition (multiple trials)
Table 1: Plant Growth with TurboGro by Trial
Trial Number
Height after 5 Days (cm) 1 30 2 31 3 4
30.5 5
AVE
Dr. Square copied Dr. Groovy’s procedure and got similar results! The plants grew an average of 30 cm in 5 days!
If scientific explanations are replicable, they are more valid and reliable.
SC.6.N.1.2 – Explain why scientific explanations should be replicable

20. SC.8.N.1.3 – Use phrases such as “results support” or “fail to support” in science, understanding that science does not offer conclusive “proof” of a knowledge claim
EXAMPLE
Hypothesis
If Turritella snail fossils are compared for height and number/location of predation drill holes, then there will be an escape size where the holes are absent, because the predators in the community would no longer be large enough to feed on the snails.
Discussion
In the study area, predation drill holes are absent on Turritella over 6 cm. The results support the hypothesis. The researcher infers that once Turritella grew to 6 cm in length, it escaped predation.
There is NO conclusive proof of this claim, as this is one study conducted in one particular study area.

21. SC.8.N.1.4 – Explain how hypotheses are valuable if they lead to further investigations, even if they turn out not to be supported by the data
Studies that analyze the strengths and weaknesses of alternative explanations are valuable.
They encourage others to more thoroughly examine the ideas and evidence and to develop new ways to test the ideas.

22. SC.6.N.1.3 – Explain the difference between an experiment and other types of scientific investigation, and explain the relative benefits and limitations of each
SC.7.N.1.3 – Distinguish between an experiment and other forms of scientific investigation and explain that not all scientific knowledge is derived from experimentation
Experiment – involves identification and control of variables
Independent variable/test variable/manipulated variable
Dependent variable/outcome variable/responding variable
Controlled variables
Field Study – observe a natural habitat without manipulating variables
Simulation – imitating a real situation or process

23. SC.7.N.1.4 – Identify test variables (independent variables) and outcome variables (dependent variables) in an experiment
Independent Variable (Test Variable):
the amount of light per day
Dependent Variable (Outcome Variable):
plant growth measured in cm