LAMARK

1
Look at the drawings carefully then answer the
following questions 1) What is the main
difference you notice about the Galápagos
finches? 2) Why do you think this difference
exists?  
2
INTRODUCTION TO EVOLUTION
What can we say about the structures in the
diagram above?
3
DEFINITION OF EVOLUTION

• change over time the process by which modern
  organisms have descended from ancient organisms.
  
• Theory A well-supported, testable explanation
  of phenomena that have occurred in the natural
  world.
• What is the support in science?
• EVIDENCE!!!
• Charles Darwin was first to propose the theory of
  evolution in 1800s

4
The Life of Charles Darwin
5
The Life of Charles Darwin

• Born 1809 (England)
• Completed college after studying to become a
  doctor but could not stand sight of blood
• Set sail on 5 year voyage on H.M.S., Beagle in
  1831 as the natural historian for expedition.

6
The Life of Charles Darwin

• Made extensive drawings and notes on the trip but
  also collected many species of plants and
  animals.
• Began to OBSERVE that animals were well adapted
  to their environments, but
• why were different animals found in areas that
  appeared to be similar in climate? And some
  survived others did not?
• Argentina
• Australia
• Europe

All had grasslands but very different animals
7
The Life of Charles Darwin

• He collected fossils.
• noticed some looked like living organisms
• others looked like nothing he had ever seen
  before
• Were these related to the living (present day)
  organisms?
• Why did some organisms disappear altogether?

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The Life of Charles DarwinGalapagos Islands

• Organisms Darwin Observed on the Galapagos
• Land Tortoise different shaped carapace (shell)
  depending what island they inhabited.
• Finches different shaped beaks depending on
  environment in which they lived.
• Through his observations and talking to other
  islanders
• he realized that characteristics of many animals
  and plants varied noticeably among the different
  islands of the Galapagos.
• On the journey home he began to pose the
  question
• Could animals on the different islands once have
  been members of the same species?

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Those Who Influenced Darwin Be sure to read
pages 374-377

• Hutton (Geologist)
• Geologic processes operate extremely slowly
• millions of years
• therefore, the earth is very old
• Lyell (Geologist)
• Scientists must explain past events in terms of
  processes that they can actually observe
• since processes that shaped the Earth millions of
  years ago continue to shape present day Earth
• This explained how geological features can be
  built or torn down over long periods of time.

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Darwin wondered

• If the earth could change over time, could life
  change as well?
• Also it must have taken many, many years for
  life to change the way Darwin had in mind
• This would only be possible if the earth was very
  old

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Those Who Influenced Darwin Be sure to read
pages 374-377

• Malthus (Economist)
• proposed that war, famine, disease, limits the
  growth of human populations
• if populations continue to grow unchecked, they
  will run out of resources (food/shelter)

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LAMARKs explanation on evolution
Law of Use and Disuse an organism can change
certain body parts during its lifetime and pass
these changes on.
ASSUMPTION 1
Implies that an organism can sense its needs and
change to meet them.
CRITICISM OF THIS ASSUMPTION
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LAMARK continued
Inheritance of Acquired Characteristics acquired
traits can be passed on to offspring ? population
changes.
ASSUMPTION 2
Suggests that changes in body cells (like
building bigger muscle mass) can be inherited.
CRITICISM OF THIS ASSUMPTION
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SUMMARY

• LAMARK
• Individuals can change

• DARWIN
• Evolution acts on populations

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New York Times Article You are a reporter for
The New York Times newspaper. It is 1836. You
have been assigned to cover a story about the
young Charles Darwin, who has just returned from
his travels to the Galápagos Islands. You are to
interview him and talk about the observations he
made on his journey. How did his observations
lead to ideas about his theory of evolution? What
has he learned from others in the scientific
community that may influence his theory (Hutton,
Lyell, Lamarck, and Malthus)? Dont forget to
give your article an eye-catching headline and BE
CREATIVE! USE YOUR OWN WORDS WHEN DESCRIBING
HIS IDEAS!
16

GRADINGthis MUST BE TYPED!!! POINTS
possible 1. Includes information
about the observations 6 made
on his trip to the Galápagos Islands
(Tortoises, birdswhat was he thinking/
learning?) 2. Includes information that Darwin
learned from 8 Hutton Lyell
Lamarck Malthus 3. Answers the
question How did his observations
of all these animals 6
give rise to his ideas about the theory of
evolution? 4. Article must have a catchy
headline, be neat, 5 well
written with few grammatical errors
_______
Total points 25