AP ENVIRONMENTAL
UNDERSTANDING SCIENCE SKILLS
CHAPTER 2
HISTORY OF SCIENCE AS A PROCESS
Ancient Egyptians
- Used scientific observations to determine when
to plant crops or how to predict human events
using astronomical signs rooted in religion
Ancient Greeks
-Theoretical approach to science. “Knowing
for the sake of knowing” by asking “Why” or
“For what purpose?”
1500’s-1600’s
-Development of the scientific method by
Gilbert, Galileo and Harvey to ask “How do
things work”
SCIENCE AS A PROCESS
• Science is a continually evolving process that leads
to generalizations, conclusions, and theories that
can always be changed with additional information
• Science does not provide a final answer to
unknowns
• Science can be frustrating because of changing
scientific conclusions.
• Examples: What diet is best? What chemicals are
cancerous?
SCIENCE AS A PROCESS
• The scientific method was first described by Francis
Bacon in 1620
• During the medieval period people believed that
disease arose from one of the four humors
• Bacon argued that all assumptions needed to be
“weighed with the truthfulness of knowledge”. He
believed that everything should be held in doubt
until proven by observation with the five senses.
SCIENCE AS A PROCESS
• The scientific method proposed by
Bacon stated that in order to test
potential truths (hypotheses) scientists
had to devise experiments that would
manipulate nature in attempts to
prove their hypothesis wrong
• He suggested that variables had to be
isolated and data collected and
analyzed using a systematic process
• He also said that nothing could be
considered a truth until the
experiments could be consistently
repeated with the same results
SCIENCE AS A PROCESS
• Today the standard for measuring the validity of a
scientific concept is whether or not the concept
can be disproved
• As a rule, if you can devise a test that would
disprove a statement then it can be considered
scientific (Reference diagram: figure 2.3)
• Does not include religious, aesthetic or moral views
because they are based on faith, belief, cultural or
personal choices
ASSUMPTIONS OF SCIENCE
• Events in nature follow patterns.
These patterns and the rules
that describe them are the same
throughout the universe
Principle of Uniformitarianism
• Popularized by James Hutton and Charles Lyell
• States that the processes that shape the Earth today are the
same processes that occurred millions of years ago and
could be found on other planets throughout the universe
ASSUMPTIONS OF SCIENCE
• Science is based on
inductive reasoning.
• Induction begins with
specific observations and
then leads to
generalizations based on
those observations
ASSUMPTIONS OF SCIENCE
• Generalizations can be subjected to tests to
disprove them if they are scientific.
• Science can never provide absolute proof of its
theories.
SCIENTIFIC PROOF
• Proof in mathematics:
• Uses deductive reasoning that tries to make a connection
between a premise(assumption) and a conclusion
• Does not require a premise to be true, only a foolproof
reasoning
Example:
Premise: A straight line is the distance
between two points.
Premise: The line from A to B is the
shortest distance between points A and B.
Conclusion: Therefore, the line from A to B
is a straight line.
SCIENTIFIC PROOF
• Proof in Science:
•
•
•
•
Uses observations
Conclusions are only as true as their premises
Requires logical reasoning and correct premises
Generalizations made this way have a high degree of
probability unless proven otherwise
Premise: Humans are the only toolmaking
organisms
Premise: The woodpecker finch uses tools
Conclusion: Therefore, the woodpecker
finch is a human being
Scientific Reasoning concludes:
If humans are the only
toolmaking organisms
and
the woodpecker finch uses
tools,
then the woodpecker finch is a
human being
SCIENTIFIC PROOF
• Science is not limited just to inductive reasoning, it
can also be deductive if the situation requires it.
• New advancements begin with insight (leaps of
imagination based on a foundation of knowledge)
and then attempts are made to prove them
through inductive reasoning
SCIENTIFIC NUMBERS
• Quantitative representations of data used to build
relationships between data sets
• All scientific measurements are made using the
International System of measurement (SI or metric
system)
• All measurements are approximations because of the
factors of uncertainty
What are some of the sources of uncertainty in
measurements?
SCIENTIFIC NUMBERS
Precision vs. Accuracy
SCIENTIFIC SKILLS
• Scientific reasoning is
based on observation
and inferences
• Observations use the 5
senses and/or tools to
describe something
• Inferences are
generalizations that
can be made based
on observations
SCIENTIFIC SKILLS
• Once an inference is made, if it is testable it can
become a hypothesis
• Hypothesis format:
If…independent variable, then…dependent variable.
Manipulated by scientist
Measured response
SCIENTIFIC SKILLS
• Variables in an experiment have to be described in
a way that would allow them to be understood by
all scientists. This is called their operational definition.
• Once an experiment has begun data must be
collected to show the relationship between the
independent variable (input) and dependent
variable (output)
• This information is recorded in either quantitative
(numerical) or qualitative (non-numerical) form
MODERN SCIENTIFIC METHOD
Make observations and ask a
question
Develop a tentative answer
(hypothesis)
Design a controlled experiment to test
the hypothesis
Collect data in an organized form
Interpret the data
Draw conclusions and compare
to the original hypothesis
Complete additional
tests/observations if necessary
ENVIRONMENTAL QUESTIONS
• The way that scientists attempt to answer
environmental questions often has to use a creative
take on the standard scientific method
• Environmental questions can deal with processes
that occur over long periods of time or organisms
that are hard to control within an experiment
The California Condor breeding
program captured all wild condors
and bred them for reintroduction
into the wild once numbers
increased. None of the reintroduced birds however were able
to find their own food.
ENVIRONMENTAL QUESTIONS
Alternative approaches:
• Historical evidence is used in cases of research into
a process or pattern that has occurred over a long
period of time. This evidence is drawn from past
reports or evidence left behind within the
environment.
ENVIRONMENTAL QUESTIONS
• Modern Catastrophes and Disturbances can create
a one time large scale experiment for studying
events and processes that relate to things like
volcanism, tectonic movement, etc.
ENVIRONMENTAL DECISIONS
• Once information has been gathered about an
issue or an environmental concept the next step is
usually to decide on some sort of action
• Decision making on environmental issues has to
balance environmental needs, social needs and
economic needs
ENVIRONMENTAL DECISIONS
• Standard decision making process:
1.
2.
3.
4.
5.
Formulate clear statement of the issue
Gather scientific information
List alternative courses of action
Predict consequences and probabilities of each action
Weigh alternatives and decide
SCIENCE AND TECHNOLOGY
• Science is a search for
understanding while technology
seeks to apply scientific
knowledge for the benefits of
humans
• Science can be both driven and
limited by technology
• Technology can have both
positive and negative effects
SCIENCE AND MEDIA
• Media coverage of scientific discoveries has
become a bigger issue because of the accessibility
of information and the numerous media platforms
that post information
• All publications of scientific
discoveries have to be
analyzed for the validity of
their claims and the sources
that have provided the
information
SCIENCE AND MEDIA
To determine the validity of a scientific article you
must:
• Identify the author or group that published the
article
• Find the origin for the claims being made
• Identify the sources used to provide information
about the claims (preferably more than one)
• Research contradictory evidence
• Research any evidence of bias from the author
• Determine if the reasoning presented is logical
SCIENCE AND OBJECTIVITY
MYTH: Scientists rely only on the facts
Scientists like all people have influences in their lives
that spill over into their work.
Do not simply trust information presented because it
comes from a scientific source. Use your own
background knowledge and research into the
information to determine if there is any bias or false
information.
LEARNING SCIENCE
• Learn science in the active mode. Listen critically
and be critical of what you see and read. Try to
understand what science is and apply it to
environmental science concepts. Make
connections among the facts presented instead of
focusing on rote memorization.
LEARNING SCIENCE
“You cannot understand
science and its relation to
anything unless you
understand and
appreciate it as the great
adventure of our time.”
“The imagination of nature
is far, far greater than the
imagination of man.”
-Richard Feynman