HuttonLyell said that

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Hutton/Lyell said that

• -Mountains, Hills and Valleys have been SHAPED BY
  erosion, heat and cold temps.
• Darwin witnessed an earthquake that lifted a
  piece of land about 8 ft in one day and THEN
  understood how sea shell fossils might be found
  ON mountains about 3 miles high from sea level.
• POINT THIS WOULD TAKE A LOT OF TIME!!!!

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Rocks are constantly being changed to alter the
landscape.
The OLD MAN OF THE MOUNTAIN- New Hampshires
state symbol
BEFORE (for 10,000 Yrs)
NOW-ROCK FACE FELL ON MAY 3, 2003
GRAVITY WINS AGAIN!!!
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What we see NOW is the product of millions of
years of nature at work...
GLACIAL ACTION AND RUNNING WATER CUT A PATH
FOR THIS INTERSTATE HIGHWAY IN NEW HAMPSHIRE
(called Franconia Notch)
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Jean Baptiste-Larmarck

• First to propose that species change over time.
• -theorized that animals when used or disused (did
  not use) certain organs, organisms gained or lost
  traits IN THEIR LIFETIME. (wrong!!-could never
  happen)

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LAMARCKS INCORRECT IDEA OF USE
AND DISUSE EXAMPLE A giraffes Neck would Get
longer During its Life if it Needed.
TO DARWIN Gave him idea That organisms could
change (if they had to in order to
survive) -BUT HE REALIZED THAT LAMARCK
WAS WRONG!!
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Ideas that shaped Darwind. THOMAS MALTHUS

• -said that if human population
• continued to grow, eventually
• there would not be enough food
• Or space to livedeath
• DARWIN THOUGHT
• This applies even more strongly to animals and
  plants since they have more offspring
• He thought, what affects who lives and dies in
• In the animal/plant world??

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Chap 15.3 Darwin Presents His Case

• Darwin returned to England in 1836
• He refused to publish his ideas on evolution as
  he knew they would be very controversial-his wife
  was told, publish them after I die
• Alfred Wallace (another naturalist) also figured
  out how species evolve during his time in the
  Malaysian rainforest

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Slide 2 (15.3)

• Fearful another man would get credit for his
  lifes work and ideas he published his very
  famous book,
• ON THE ORIGIN OF SPECIES
• In 1859
• Some said he was brilliant
• Others said it made no sense and he was a fool.

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Slide 4 (15.3)

• SUMMARY of Darwins ideas
• There is NATURAL VARIATION among all living
  things. This seems obvious today but was a
  revolutionary idea then.
• Evidence Some cows give more milk than others.
  No two dogs are exactly the same in appearance or
  temperament (even within a breed)

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Rottweilers Bred to be
aggressive/protective
THERE ARE NATURAL VARIATIONS EVEN AMONG THE SAME
SPECIES OF DOGS (All dogs are not the same) NOTE
ALL DOGS ARE SAME SPECIES BUT DIFF
BREEDS! Scientific Name Canis familaris
Labrador Retreivers Bred to be child- friendly
(a family dog)
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Slide 5 (15.3)

• In selective breeding farmers/breeders took
  advantage of natural variations by picking and
  crossing the BEST livestock (or fruit) to make
  more of the same.
• Darwin called this ARTIFICIAL SELECTION as humans
  selected those characteristics in species they
  liked the best.

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These variations have occurred Naturally
without Humans being Involved.this is
what, naturally Occurring means
Example Farmers have Artificially
selected which variation is most desireable(prof
itable) And bred more of them for us to eat.
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Slide 6 (15.3)

• Darwins Ideas (continued)
• B. STRUGGLE FOR EXISTENCEHigh birth rates/lack
  of things like food to feed everyone lead to a
  struggle for existence. This is important to
  evolution!!
• C. FITNESS IS A RESULT OF ADAPATATIONS The
  species that are most fit or well-suited to their
  environment tend to survive and reproduce. Those
  that are not perishgenes are lost
  foreverextinction!

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Slide 7 (15.3)

• Adaptations are any inherited trait that helps an
  organism survive in the wild.

The quills help this small porcupine from being
lunch!
POINT ANIMALS/PLANTS APPEARANCE IS NOT
AN ACCIDENT. SOMEHOW IT HELPS THEM TO
SURVIVE-(its not always as obvious as this)
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Slide 8 (15.3)

• D. SURVIVAL OF THE FITTEST
• Those species with a high level of fitness
• (they fit into their environment) live to
  reproduce offspring similar to themselves.
• DARWIN CALLED THIS NATURAL SELECTION Nature
  selects some individuals to live/die based on
  fitness

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Slide 9 (15.3)

• Over long periods of time, this results in
  changes (modifications) of a population to
  produce the best possible fit to their own
  unique environment. Ex. The forest, the North
  Pole, etc.
• THE RESULT?
• A population that is better suited (adapted)
• to some aspect of their environment than they
  were before.

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Slide 10 (15.3)

• Descent with Modification
• -means every living species has descended, with
  changes, from other species over time.
• Principle of Common Descent
• -all species (still living or extinct) came from
  similar ancestors. A tree of life unites all
  living things.

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Slide 11 (15.3)The Evidence for Evolution

• Darwin said that evolution has been taking place
  for millions of years.
• Evidence for this?
• A. The Fossil Record
• B. Geographic distribution of species
• (why are there kangaroos in Australia but
  not anywhere else?)
• C. Homologous (same) body structures
• D. Similarities in early development

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Slide 12 (Chap 15.3)Evidence for Evolution

• The Fossil record
• -Different fossils found in different layers of
  rock show changes in the types of things that
  have lived

Fossils are traces or parts of ancient Organisms
preserved (usually in Sedimentary rock).
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Note Different layers of Rockshown by
horizontal lines
Fossil remains Embedded in rocks Tell you
what ived when and what It looked like
Top Layers Youngest Rock
Bottom layers Oldest Rock
Evolution sees a similarities in Fossil remains
in each successive layer of rock (you Can
actually see a species Changing.
(most recently pushed up from inside the Earth
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Slide 13 (15.3)Evidence of Evolution

• B. Geographic distribution of living species
• It has been discovered that the same species (or
  nearly same) of animal are living on continents
  close to each other.
• Why? Because the continents were once joined.
• They are different however because they evolved
  in different environments. This is proof that
  adaptations occur.

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SIMILAR FOSSILS HAVE BEEN FOUND ON THE WESTERN
COAST OF AFRICA AND EASTERN COAST OF S.
AMERICA This supports -Theory of Continental
Drift (continents were once joined and
separated) -Evolution because you can clearly see
species were related even though now they are
separated by about 3000 miles of ocean now.
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Slide 14Evidence for Evolution

• C. Homologous Structures
• Many animals have similar structures
• Ex. Backbones, arms, legs, wings. Etc.
• This is evidence that all 4 limbed animals with
  backbones are related to ancient animals. (why?
  SAME DNA!)

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Note similar (homologous) structures

• Observe similar joints and fingers

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Slide 15Evidence for Evolution

• Vestigal structures (traces of ancient
  structures) NO LONGER NEEDED! (but not necessary
  for survival so still exist)
• Ex. Human appendix, tailbone

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D. Similarities in Early Development

• Human embryos look very similar to other animals
  with backbones, ex. Fish, birds
• Similarities mean we probably come from common
  ancestors millions of years ago.

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