What do we know about science? - University of Southern California

What is Science?
What is science?
Science is that activity, the underlying
aim of which is to further our
understanding of why things happen as
they do in the natural world.
It accomplishes this goal by applications
of scientific method—the process of
observing nature, isolating a facet that is
not well understood, and then proposing
and testing possible explanations.
-S. Carey, 2004
What is science?
 Way of knowing
 Study of natural world (process)
 Involves observing, proposing explanations,
testing explanations
 Evidence-based
What is science?
 Know, use and interpret scientific explanations of
the natural world
 scientific knowledge (content)
 Generate and evaluate evidence and explanations
 scientific reasoning, using evidence (process)
(National Research Council, 2007, Taking Science to School)
What is science?
 Understand the nature and development of
scientific knowledge
 how science works (nature of science)
 Participate productively in scientific practices and
 how to talk/think about science, how to use scientific
knowledge, engage in scientific practice
(National Research Council, 2007, Taking Science to School)
Be careful…
 Sometimes we think science can do
things it can’t OR does more than we
think--there are
Common Science Myths
 When exposed to the vacuum of space, the
human body pops.
 a human can survive for 15 – 30 seconds in outer space
as long as they breathe out before the exposure
Food that drops on the floor is safe to eat if you
pick it up within five seconds Um, no..
but eating germs and dirt is not always a bad thing as
it helps us to develop a robust immune system
Common Science Myths
 Brain cells can’t regenerate – if you kill a brain
cell, it is never replaced.
 In 1998, scientists at the Sweden and the Salk Institute in
La Jolla, California discovered that brain cells in mature
humans can regenerate. An old dog CAN learn new tricks!
A penny dropped from a very high building can
kill a pedestrian below
the aerodynamics of a penny are not sufficient to make it
dangerous. What would happen in reality is that the person
who gets hit would feel a sting
Public Views of Science
 U.S. science is tops, but most Americans don't think it
is, a new survey finds. By Mandy Kendrick | Jul 9, 2009 04:15 PM
 84% of the public felt that “science’s effect on society”
has been mostly positive, with only 6% considering it
mostly negative Posted on July 15, 2009 by speakingofresearch
 Study finds public relatively unconcerned about
nanotechnology risks Published: Tuesday, April 12, 2011 - 09:36 in
Health & Medicine
Dangers of Science
That which we don’t understand can be looked at as
good or evil – science illiteracy
The “magic” of science with little understanding of
how it works can be a dangerous state of affairs.
The Nature of Science
 Content, process, nature
 How does science lead to new knowledge?
 What can science do?
 What can’t it do?
a Nature of Science quiz…
What do you know about science?
(Answer True or False)
1) Science is a system of beliefs.
2) Scientists are totally objective in their work
3) The scientific method is the basic, 5-step
guide for conducting scientific research.
4) Doing science involves creativity.
5) Scientific ideas are tentative and can be
modified or disproved, but never proved.
1. Science is a system of beliefs
 Many students, science teachers, and the general public
often believe that science is a system of beliefs
 Scientific ideas are established only after compelling
evidence has accumulated from observations of nature.
 Scientists use reasoning and imagination, study the
work of other scientists, and collaborate with other
professionals, always looking for evidence to support
or disprove their ideas.
2. Scientists are totally objective in
their work.
Science involves some subjectivity.
 Humans do sciencehumans are subjective
SO…science involves subjectivity
 Personal experience and expectations influence
 How do we "get around" this?
Controlled settings
Repeat tests
Confirmation from other observers
Large sample sizes
Perceptions and Bias
 Work in groups of 4.....
 * Keep the 'checks' (evidence) hidden in the envelope.....
 * Pull out ONLY 3 checks, and discuss with your group
what situation the checks imply
 * Record the implied scenario.....
 *Now, pull 3 more checks and modify the scenario........
 * Now, pull 3 more checks and further modify the
 * Publish your results by describing your analysis to the
Perceptions and Bias
 This is an excellent way to experience the very real fact
that even in science, cultural biases and experiences
DO influence interpretations (and even perceptions).
 Scientists typically collaborate, share ideas through
conventions, meetings, and publications, much as you
were doing as you discussed the checks.
What do you see?
What do you see?
What do you see?
 Inference is when observations are influenced by
prior knowledge and beliefs
 Being able to infer is a survival mechanism, so it
is positive.
 Inference doesn’t make science weak, but rather
forces us to be careful in our observations and
interpretation of evidence
What happened here?
What do you OBSERVE?
what do
Infer what happened based on your
 Any information collected with the
 The skill of describing scientific events.
 __________Inference______________
 Conclusions or deductions based on
observations .
 The process of drawing a conclusion
from given evidence.
What happened here?
 Be sure to distinguish observation and inference.
 Prior knowledge affects observation!
 Not all evidence leads to one answer.
 Not all scientific knowledge is gained through
controlled experiments. (Paleontology for instance)
3. The scientific method is the basic, 5-step
guide for conducting scientific research.
 There is no universal scientific method.
 There are methods, but not a single pathway
 Observations (before, during, after)
 Proposing explanations based on observation
 Testing explanations or predictions
Using senses to gather
Observations lead
to questions
 How does sand
grain size affect the
size and abundance
of crabs?
Two types of Observations
 Qualitative:
 Quantitative:
 Uses senses to
 Uses tools to take a
 Ex: color and
consistency of sand,
minerals present etc.
 Ex: actual size of
grains, actual size
and number of crabs
at various sites.
Predicts the answer
to a question
Hypothesis are based on:
Past experience
Test your prediction by
designing an experiment
Collect data and and analyze
4. Doing science involves creativity
 Scientific explanations and data interpretation
involve creativity and imagination.
 Science involves ‘making leaps’ and ‘thinking
outside the box.’
Inquiry Cubes
2. Arrange in groups of 2 or 3 at each table.
You will be provided with a cube that will
be placed in the center of your table.
Do not touch, turn, lift, or open the
Inquiry Cubes
3. Your group will focus on the question:
 You will have to answer the question by
proposing an explanation, and must convince
other colleagues that your answer is BASED ON
 Use your observations to propose an answer to
the question: What is on the bottom of the cube?
 Be ready to present your reasoning for this
Inquiry Cubes
Use your observations to make a prediction of the
number in the upper right corner of the bottom.
 Your team needs to decide which corner of the
bottom you wish to inspect and why you wish to
inspect it.
- Lift the designated corner LESS THAN ONE
INCH and look under the corner.
 Describe the data gained by the “experiment.”
 Be ready to share a summary of your
Inquiry Cubes
6. In your same groups, create a cube that will be
used as the evaluation exercise for other
groups. The focus question for evaluation will
be: What is on the bottom of the cube?
 Exchange your cube with another group.
All procedural directions are the same as for
Cube 2.
 What is on the bottom face of this cube?
 You made observations of the other sides in order to
provide a prediction and a hypothesis
 You used the scientific process of inferring to come to a
conclusion about what is on the bottom of the cube
 As in ‘real science’ you needed to be organized and
 As in ‘real science’ you needed to recognize patterns
 Recognizing patterns in science involves the important
process skill of categorizing (although this activity is
mainly about inferring)
5. Scientific ideas are tentative and can be
modified or disproved, but never proved.
 Tentative but durable--an important
characteristic (strength) of science
We can't look at ALL possible cases or
combinations, past present or future.
One bit of evidence that contradicts an
explanation requires us to come up with a new
Doesn't mean scientific explanations are bad
or inadequate—we know that based on the
evidence at hand, this explanation is durable
Dead words, caution words
Prove or proof
 Avoid these: use support or evidence
Word to avoid: ‘PROVE’
 Science can’t really PROVE anything
 Scientific knowledge is based on evidence-lots and lots of tests, observations, etc.
 But none of the methods of science allow
us to examine every possible case--past,
present and future. We can’t presume to
know this (not part of natural world)
Word to avoid: ‘PROVE’
 We can DISPROVE an explanation or
generalization by finding conflicting evidence.
 A strength of science is the fact that it is
falsifiable (can be disproved)--it is not dogma.
 Science can correct itself--new theories replace
old theories when the evidence fits better with a
new explanation.
 As researchers, it’s better to talk about
“supporting your case” or “providing evidence”
than “proving” something.
The case of the oviraptor…
Egg-stealer or
good parent?
The case of the oviraptor…
The oviraptorid
Ingenia on a nest.
Photo © Rob Gay
 A recent study found an oviraptorid embryo inside one
of those eggs, so actually the oviraptor was by its own
nest! More expeditions have found oviraptor skeletons
on top of nests — these devoted parents apparently
died in sudden sandstorms while guarding their nests!
Just recently, one of the most amazing fossils ever
found was announced — an Oviraptor skeleton
brooding a clutch of eggs, just like a bird does.
What is a scientific theory?
 An explanation based on repeated
observations, and/or repeated testing.
 They can be used to explain numerous
observations and patterns
 They may change, however, given new
contradictory evidence.
 A well-substantiated explanation of
some aspect of the natural world. (Backhus)
What is a scientific theory?
 Example: Atomic theory
Atoms consist of protons, neutrons, electrons.
Electrons are negatively charged, protons are
positively charged, neutrons have no charge.
This explains LOTS of observations, patterns
Chemical reactions (entire branch of science based
on this!) Even things like electrical circuits!
There is no “guessing” here—scientists use this
theory to predict outcomes and make other
The problem with ‘theory’
 In everyday language, ‘theory’ refers to
something untested or very tentative
 ‘She had a theory as to why her boyfriend was
always late.’
 The word has a different meaning depending on
the context.
 We must be aware of how we use terms that
have different meanings in different situations.
What is a scientific law?
 Scientific Laws describe patterns, predict
outcomes (description)
Law of gravity
 There is an attractive force between any two
bodies. This force depends on the size of the
objects and the distance between them.
 There is no explanation for this. No answer
to ‘Why?’
 Can be used to predict future observations
 Laws can sometimes be expressed as
mathematical expressions too.
Be careful…
 Scientific theories become scientific laws
when they are proven.
Law vs. Theory
Laws describe
Two DIFFERENT things
Theories explain
 Scientific Theories don’t become Scientific
 A theory might explain a law, but it can
NEVER become one.
Consistency : The results of
observations and/or experiments are
reasonably the same when repeated.
1. Green plants will grow towards a light source.
2. Walking under a ladder will cause bad luck.
Observability : The event or evidence of
the event, can be observed and explained.
The observations are limited to the basic
human senses or to extensions of the
1. Some plants eat meat.
2. Extraterrestrial beings have visited
List the differences you see
Natural : A natural cause (mechanism)
must be used to explain why or how
the event happens.
1. Green plants convert sunlight into
2. With a rod, Moses parted the sea so his
people could cross to the other side.
Predictability : Specific predictions
can be used to foretell an event. Each
prediction can be tested to determine
if the prediction is true of false.
Without sunlight (or artificial light), green plants
will die.
2. If you are a "Scorpio", your horoscope for today is
"You'll be saying 'I feel rich !' Lunar position
highlights back pay, refunds, correction of
accounting error."
Testability : the event must be
testable through the processes of
science, and controlled experimentation.
1. The Bermuda Triangle causes ships and
planes to sink and disappear.
2. Life comes from life and cannot come
from non-life.
Tentativeness : Scientific theories are
changeable and correctable, even to the
point of the theory being proven wrong.
Scientific theories have been modified
and will continue to be modified
1. The number of human chromosomes was
once "known" to be 48, but is now considered
to be 46.
2. We know that the world began about 6000
years ago.
Emerging Science
 Also called protoscience, a “near science”
 Tends to conform to CONPTT, but falls short
in one or two criteria
 Consistent observations and predictions
limited by knowledge and/or technology
 Ex: mental telepathy
 Does not meet criteria of CONPTT
 Topic that can be very logical but not fall
within realm of science
 Ex: belief systems, philosophy, ethics
False Science
 Also known as pseudoscience
 Non-science portrayed as a legitimate science
 Ex: astrology, creation science
The last observation!
Moon over North Carolina….. Can you see Santa?
Checks Lab can be found at:
Inquiry Cubes – variations
(my temporary website!)

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