Six Criteria of Science

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Six Criteria of Science
CONPTT
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Consistency The results of observations and/or
experiments are reasonably the same when
repeated.

• Green plants will grow towards a light source.
• Walking under a ladder will cause bad luck.

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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 senses.

• Some plants eat meat.
• Extraterrestrial beings have visited Earth.

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Natural A natural cause (mechanism) must be
used to explain why or how the event happens.

• 1. Green plants convert sunlight into energy.
• 2. With a rod, Moses parted the sea so his people
  could cross to the other side..

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Predictability Specific predictions can be used
to foretell an event. Each prediction can be
tested to determine if the prediction is true or
false.

1. Without sunlight (or artificial light), green
   plants will die.
2. If you are a "Scorpio", your horoscope for today
   is Lunar position highlights back pay, refunds
   and money!!!!!"

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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.

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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

• The number of human chromosomes was once "known"
  to be 48, but is now considered to be 46.
• We know that the world began about 6000 years
  ago, and nothing will change that.

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Scientific Method

• Observation
• Gather Information
• Hypothesis
• Experiment
• Conclusion

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Observation

• Using senses to gather information
• Observations lead to questions

• what is the effect of on ?

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Two types of Observations

• Qualitative
• Uses senses to describe
• Ex Mrs. Forsythe has RedHair

• Quantitative
• Uses tools to take a numerical measurement
• Ex Mrs. Forsythe is 5 ft 8 in.

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Hypothesis

• Predicts the answer to a question
• BASED ON
• Past experience
• Observations
• Research

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The format for writing a hypothesis

• IF . . . THEN . . .because.
• Example If we increase the temperature of the
  fishs water, then the breathing rate will
  increase because breathing rate is dependent upon
  temperature.

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Experiment

• A Test of your hypothesis
• Experiments tests a VARIABLE (factor that
  changes)
• Example Variable change in breathing rate
• Experiments need a CONTROL GROUP (to compare)
• Control Group breathing rate at room temp

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Types of Variables

• Dependent Variable
• Is the data collected through observation and
  measurement
• Ex Breathing Rate
• Independent Variable
• Variable that is manipulated (changed) during the
  experiment.
• Ex Water Temp

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Conclusion

• 4 parts
• Did the experiment support the hypothesis?
• If you did the experiment again, what would you
  do differently?
• What did you learn?
• Possible Errors

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What Factors effect Plant Growth?

• Experimental Design
• Activity

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EVOLUTIONARY THEORY
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Theory

• theory hypothesis supported by many
  experiments over time
• Examples of theories
• Big Bang Theory
• Theory of Plate Tectonics

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• Jean Baptiste Lamarck Evolution occurs as
  structures develop through use, or disappear
  because of disuse, and these
• acquired characteristics
• are passed to offspring

EXAMPLE Over a Giraffes Lifetime it can stretch
its neck and its offspring will be born with
long necks. Valid?
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Darwin and The Monkey!
THIS IS NOT WHAT HIS THEORY SAYS
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Who was Charles Darwin

• Studied Medicine
• Hated the sight of blood
• Received a BA in Theology
• Had 10 children

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Theory of Evolution

• Darwin was an Naturalist on the HMS Beagle
• In The Galapagos Islands, Darwin collected
  species of finches (13)
• Each had a specialized diet and way of obtaining
  food.
• These finches all closely resembled a South
  American finch species
• Hypothesized that the differences were do to
  gradual change

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Darwins Finches
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Theory of Evolution

• Darwin referred to such change as descent with
  modification evolution
• Wrote Origin of Species
• He still wondered
• How does evolution occur?

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What is Evolution
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• After his voyage, Darwin made following
  inferences
• There is variation within populations
• Some variations are favorable (better)
• Not all young each generation can survive
• Individuals that survive and reproduce are those
  with favorable variations
• And then those traits will increase in a
  population and population will slowly change

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• Darwin called this process by which populations
  change in response to their environment
• Natural Selection

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Evolution happens because of natural selection
Selection acts on individuals, populations evolve
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Change creates advantages for some species
disadvantages for others

• Fossils reveal changes in species over millions
  of years

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Adaptation

• Adaptations are inherited traits that increase a
  groups chance of
• survival reproduction

This type of finch has a thick beak ? adaptation
for cracking open seeds
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Variation

• Within a species, there is variation
• Variation differences between members of a
  population
• Species group that can breed produce healthy
  offspring

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Evidence for Evolution

• 1. Fossils show change over time
• scientists can date fossils use them to support
  the theory of evolution
• common ancestors reveal whether species are
  related
• Anatomy of living species also
• shows relatedness

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How Anatomy supports Evolution

• Homologous Structures
• Traits similar in different species because they
  share a common ancestor
• Ex human arm, dog front limb, horse leg, whale
  fin

Look the Same
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• 3. Analogous structures
• Distantly related species have structures that
  have the same function but are different in
  structure
• Ex wing of butterfly bird

Work the Same
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• 4. Vestigial structures
• Structures reduced in size often unused
• Remains of functional structures inherited from
  an ancestor
• Ex leg hip bones in pythons whales

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5. Molecular Evidence

• Also called biochemical evidence
• Compares biomolecules such as DNA or amino acid
  sequences between organisms
• Related organisms have more of the same molecules
  in common

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How Do New Species Form?
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How do new species form?

• Geographic Isolation
• When members of a population are separated
• Ex polar, grizzly, black bears

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• 2. Reproductive Isolation
• When members of a population cant breed even
  though they live nearby
• Ex different mating seasons or different mating
  calls

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Different Types of Evolution

1. Divergent evolution
2. Convergent evolution
3. Coevolution
4. Adaptive radiation

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Divergent Evolution

• Isolated populations evolve independently
• Ex polar grizzly bears changed independently
  due to different habitats

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Convergent Evolution

• Unrelated species become more alike because they
  live in similar environments
• Ex shark dolphin

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Coevolution

• Species that interact closely adapt to one
  another
• Ex flowers hummingbirds

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Adaptive Radiation

• Evolution of many diverse species from one common
  ancestor
• Ex famous Galapagos finches discovered by Darwin

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How fast does evolution occur?

• Gradualism
• One species changes slowly eventually becomes
  two species
• This idea is supported by fossil evidence

• Punctuated Equilibrium
• Stable with short periods
• of change during which a new species forms