evolution theory
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Transcript evolution theory
The Theory of
Evolution:
A Theory based upon the
similarities and differences of
life-forms alive and extinct
When Did Evolution begin?
The answer is in these
questions…
How has the Earth changed from
the past to the present?
What has caused the changes?
Will the changes in the Earth
ever cease to happen?
Proof the Earth has Changed:
Land formations have changed
Earth’s Climate has changed
Life was once only found in marine
environment
Dinosaurs were in the past dominant
form of life on land; Today mammals
are
Causes of Earth Changes
Land Changes caused by Plate
Tectonic Forces
Climate Changes caused by Drifting
Continents, Volcanoes, Outer Space
Events
Life from sea to land caused by
Dropping Sea levels and Ozone layer
allow for live to go on land
Mass Extincions caused by Space
Impact/ ASTEROIDS & COMETS
What is Evolution?
A change in an organism
throughout time.
Success = existence
Failure = extinction
Things organisms must do to
survive
1.
2.
3.
4.
5.
Must be successful each day
Acquire Energy/Feed as needed
Exchange gases/ Respire as needed
Reproduce / Breed to pass on DNA
Structure / Body Plan no injury or
flaw
6. Mobility / Ability to move
What causes Evolution?
Evolution is caused by the idea of
Natural Section
Natural Selection is survival of the
fittest
Only strongest organisms will be left
to reproduce; others will die before
being able to reproduce
This process causes the organism to
EVOLVE over time
4 Major Forces of Natural
Selection (4 Factors of
Evolution)
1.
2.
3.
4.
Environmental Factors
Disease Resistance
Competition for Food
Predator Influence
Evolutionary Success:
Lionfish
What creates Evolution?
Variations within a
species:
some variations good: aid
survival
some bad: early death
What is a Variation?
A change in the appearance or
behavior of one organism to another
of the same species
If positive, allows for greater
survivability for the organism: THIS
IS CALLED AN ADAPTATION
IS this a Variation or Adaptation?
EXAMPLES of ADAPTATIONS
Webbed Feet on duck
Coloration to environment
Waxy coating on leaves
poison
INABILITY TO ADAPT TO CHANGE
LEADS TO EXTINCTION
3 Types or Patterns of
Evolution:
1. Divergent Evolution
share common ancestor
but look totally different
today
Hoofed animals and
whales/dolphins
Types of Evolution
2. Convergent Evolution
Share totally different
ancestor but look similar
today
dolphin and shark
Types of Evolution
3. Parallel Evolutionrelated animals evolve in
same way for long period of
time
deer and antelope
Evolutionary Question?????
Is it possible for an organism
/ life form to successfully do
all the aforementioned items
and still be threatened with
the possibility of
extinction??????
Evolution Proposed by
Charles Darwin:
Studied and collected thousands of lifeforms during 5 year journey
most famous for his observations on the
Galapagos Islands
studied and observed 14 different kinds of
finches on the islands
found one dominant type on each island;
each one was different
Charles Darwin: Reflection of his
Observations
Studied findings on finches and other
life-forms for 20 years
from his studies wrote book entitled
The Origin of the Species in 1859.
Was not well received; went against
religious beliefs
revolutionized modern scientific
thought
Charles Darwin: The Finches
14 different versions of finches
existed on Galapagos Islands
Usually only 1-2 types of finch
located on an island
major difference between finches
was beak size; shape
beaks were deciding tool in success
failure of birds to survive
beaks were primary tool for food
Charles Darwin: Reflection of his
Observations
Studied findings on finches and other
life-forms for 20 years
from his studies wrote book entitled
The Origin of the Species in 1859.
Was not well received; went against
religious beliefs
revolutionized modern scientific
thought
Charles Darwin: 4 Main
Points of Book
1. All organisms produce more
offspring than can survive
2. Variations exist in all populations of
species
3. Some variations are better than
others; more beneficial for survival
4. Overtime offspring of more
successful organisms will make up
the population of species
Charles Darwin: The
Outcome
Book basically states that Natural
Forces are primary reasons for a species
evolving; not divine powers
Evolution, therefore continually is
happening
Variations acted upon by Natural
Selection Forces (En, Dis, CF & Pred)
Variations are caused by numerous
factors most likely of which are
mutations in an organisms DNA, that
then are passed on (modern genetics)