What is Science?

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What is Science?
OCN 201
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Science as a Way of Knowing

• Science
• A way of investigating the world in order to form
  general rules about why things happen

Pure Science- pursuit of knowledge
Applied Science- search for practical uses of
scientific knowledge
Pain relief in terminal cancer patients
tetradoxin
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Characteristics of Scientific Explanations
Science is empirical. It relies on observation
and experience. The phenomenon studied must be
measurable. Phenomenon that cannot be
measured Is this painting beautiful? Does
God exist? It must be consistent with known
natural laws and well-established,
well-documented existing theories. It must be
derived objectively from independently
confirmable observations. All scientific
knowledge must be regarded as tentative.
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Scientific statements must be testable and
reproducible (i.e., valid reliable).
Hypothesis Overfishing Antarctic Krill has an
effect on the Antarctic food web. Hypothesis The
fibropapilloma virus causes tumors in green sea
turtles. Hypothesis Hydrothermal vent bacteria
are the primary producers in the deep
sea. Hypothesis Bioluminescent fish are better
predators.
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When did the study of science begin?
32,000 years ago Paleolithic paintings on cave
walls and recordings on bones- observations
7,000 B.C. to 6th century B.C.
Mesopotamian cultures- written record of
astronomical observations, chemical substances,
disease observations, mathematical tables and
calculations
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Aristotle (384-322 B.C.)

• Scientific method (observation, inductive
  reasoning)
• Described hundreds of marine species
• Dolphin is a mammal
• The earth is round
• Biology (spontaneous generation)- disproved by
  Francesco Redi (1668), an Italian doctor who
  proved maggots came from flies.

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Ptolemy (170 A.D.)- geocentric universe
Copernicus (1500s)- heliocentric universe not
accepted until 100 years after his death
Galileo (1600s)- physicist, astronomer,
scientific method
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Darwin- HMS Beagle (1831)
Subsidence theory Origin of Species (1859)
Galapagos Islands, Ecuador
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Wegener (1915)
Continental drift theory
248 mya
Pangaea
65 mya
present
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Science Disciplines
Physical Sciences
Biological or Life Sciences
Physics Astronomy Chemistry Geology
Botany Zoology
Oceanography Marine biology Embryology Anatomy Eco
logy Genetics Microbiology
Aerospace Engineering Agronomy
Biochemistry Biophysics Biomath Bioengineering
TECHNOLOGY
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Scientific Method
A way to answer questions
Must be testable repeatable, i.e., validity and
reliability
Deductive Reasoning- general to
specific reasoning from general theories to
account for specific experimental
results (theory-data collection-analysis)
Inductive Reasoning- specific to
general reasoning from specific observations and
experiments to more general theories (data
collection-analysis-theory)
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Lost at Sea
January1992 in the North Pacific
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Rubber Duckies and Ocean currents.

• In Jan. 1992, a container loaded with 29,000
  rubber ducks, was damaged and lost overboard.
• Jim Ingram (NOAA scientist)- offered a reward
• He graphed and studied the data as it came in.
• Eventually he made an inference and created a
  hypothesis that the ocean currents were moving
  the ducks in about the same speed and direction
  that the currents were going!

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Toy trek Researchers expect some 29,000 bath toys
lost at sea in 1992 to make the ice-covered trek
over the North Pole and to the North Atlantic by
this summer.
Inductive or Deductive Reasoning?
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Population cycles in
Snowshoe Hares vs. Lynx.
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• Population cycles in Snowshoe Hares vs. Lynx
• Scientists collected data between 1850 to 1930 on
  the population of hares and lynx.
• Data was from of pelts sold by trappers to the
  Hudson Bay Company!

Scientists observed an oscillation of population
density
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• As the population of Snowshoe Hare increased or
  decreased, the population of Lynx increased or
  decreased too.
• Later the scientists made an inference (inferred)
  and created a hypothesis that the populations of
  Snowshoe Hare and Lynx depended upon each other.
• Scientists made inferences from their
  observations (Inductive reasoning).
• Each inference helped them develop a general
  conclusion, and form a hypothesis.

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• However, just because the scientists used
  inductive reasoning doesnt necessarily mean that
  the hypothesis is true!
• Further observations failed to support the
  current hypothesis.
• New data showed that populations of Snowshoe hare
  on islands without Lynx had similar population
  changes as those with Lynx!
• This means the Snowshoe hare population is not
  dependent upon the Lynx population. (However, the
  Lynx may be dependent upon the amount of Snowshoe
  Hare.)
• Thus the data was accurate, but the hypothesis
  wasn't.

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Scientific Method
Observations
Question
Formulate Hypothesis
Conduct Experiment to test Hypothesis
Analyze Results
Conclusions
Discussion
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Observation
The car wont start when I turn the ignition.
Question
Hypothesis
Test hypothesis
Analyze Results
Draw Conclusion
New hypothesis
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Ben Franklin the Gulf Stream
Observation
Question
Hypothesis
Test hypothesis
Analyze Results
Draw Conclusion
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Scientific Method

• Observations
• Suggest questions to investigate
• Question
• Why does something happen
• Hypothesis
• An educated guess
• A testable explanation for an observation

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Scientific Method

• Conduct Experiment
• Process of testing a hypothesis or prediction by
  gathering data under controlled conditions
• Control vs Experimental Group
• Control group a group that has not been exposed
  to some factor (variable)
• Experimental group a group that has been exposed
  to the factor (variable)
• Independent variable (IV) the variable you
  manipulate that you believe will affect the DV
• Dependent variable (DV) the outcome variable,
  i.e., variable you measure

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Scientific Method

• Collect, organize, analyze data
• Determine whether data is reliable
• Determine whether data supports or does not
  support the hypothesis or prediction
• May use statistics
• Compare data from other studies
• Determine relationships
• Determine experimental error

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Scientific Method

• Theories
• Unifying explanations for a broad range of
  observations
• Based on testing a collection of related
  hypotheses
• The solid foundation of science
• Can be revised given new evidence

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Scientific Method

• Drawing Conclusions
• To understand something not previously understood
• To produce a model
• Construct a representation of an object, a
  system, or a process to help show relationships
  given the data
• A model is an explanation supported by data
• Use the model to generate new hypotheses or
  predictions

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Experimental Design
Confounding factors factors that were not
accounted for in the design that may affect the IV
Biased sampling A sampling technique that does
not give you a representative sample.

• Method for Reducing Bias
• Randomization in sample selection

Randomization Ensures that each subject in a
population or each site used for sampling has an
equal opportunity of being selected.
ReplicationThis is necessary to estimate the
degree of chance variation among samples.
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Experimental Design
Sample Size The larger the sample size, the
better. A larger sample size tends to give you a
closer estimate of the true population mean.
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Coral Reef Benthic Habitat Point and Area
Assessments Kaneohe Bay, HI

• Large sample size
• Random sampling

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Mangrove Study
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Mangrove Study
Select a large sample size
Randomly divide the sample into 2 groups
Treat the groups equally in all ways but one
Observe or make measurements
Compare results
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Observation
The endangered Hawaiian monk seals population has
been decreasing over time.
Question
How does commercial fishing effect the health and
reproductive success of monk seals?
Hypothesis
H0 Commercial fishing operations has no impact
on the health and reproductive success of seals .
Variables
disease, pollution, other predators on food
supply or monk seals themselves
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Contrasting Hypotheses, Theories, and Laws
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Scientific Hypothesis
A tentative scientific explanation (educated
guess) that attempts to answer questions asked
about natural phenomena.
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Scientific Theory

• A widely accepted, well documented statement that
  addresses and explains many independent
  observations of nature.
• should be rational and logical
• should be relevant
• should be extensible

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Natural Law
A description or rule for how nature appears to
behave. A law has a small likelihood of being
found incorrect. Mainly found in physics and
chemistry.
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Mendels Law of Inheritance
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Newtons Law of Gravity
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First Second Laws of Thermodynamics
Matter Energy
Entropy
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The Blind Men and the Elephant


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The Blind Men and the Elephant (Saxe 1816-1887)
I. It was six men of Indostan To learn much
inclined, Who went to see the elephant (Though
all of them were blind), That each by
observation Might satisfy their mind. II. The
First approached the elephant, And happened to
fall Against his broad sturdy side, At once began
to bawl Bless me!but the Elephant is very like
a wall!
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III. The Second, feeling of the tusk , Cried,
Ho!what have we here So very round and smooth
and sharp? To me t is mighty clear This wonder
of an Elephant Is very like a spear! IV. The
Third approached the animal, And happening to
take The squirming trunk within his hands, Thus
boldly up and spake I see, quoth he, the
Elephant Is very like a snake!
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V. The Fourth reached out his eager hand, And
felt about the knee. What most this wondrous
beast is like Is might plain quoth he T is
clear enough the Elephant Is very like a
tree! VI. The Fifth, who chanced to touch the
ear, Said, Een the blindest man Can tell what
this resembles most Deny the fact who can, This
marvel of an Elephant Is very like a fan!
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VII. The Sixth no sooner had begun About the
beast to grope, Than seizing on the swinging
tail That fell within his scope, I see, quoth
he, the Elephant Is very like a
rope! VIII. And so these men of
Indostan Disputed loud and long, Each with his
own opinion Exceeding stiff and strong, Though
each was partly in the right, And all were in the
wrong!
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Moral. So, oft in these theological wars The
disputants, I ween, Rail on in utter ignorance Of
what each other mean, And prate about an
elephant Not one of them has seen!
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The Blind Men and the Elephant, Part 2,
I. They talked, those men from Indostan While
standing at the door, Of elephants and how they
looked (This talk was such a bore!), At last they
agreed that the knowledge gained Required
something more. II. Perhaps each one in his own
way, Did learn a bit Of the beasts elusive
mystery, But just a part of it With work, they
thought, that they might see The puzzle pieces
fit.
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III. Twas obvious to all of them For learning to
progress, That they must share in what they
found Jointly sort out the mess. And seek to
fully understand Elephants, more or
less. IV. Some worked alone and some in
teams, In both the field and lab. Models were
made some soft, some hard Some good, some pretty
bad. But when they pooled the useful work, And
truth they made a grab.
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V. They checked each others methods out, Some
kept, some put asunder. To use the ones which
passed the test Reduced the chance of
blunder. Then theyd trust what they had
learned Of elephants fine wonders. VI. They
made great strides in what they knew Of the
nature of the beast. Of what and where and how
and why They knew much more at least. For blind
men learned how best to learn And vision soon
increased!
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Inquiry

• What is the difference between a hypothesis,
  theory and law?
• Can a theory ever be proven?
• In the mangrove study, what is the dependant
  variable?
• State Ben Franklins hypothesis.