Chapter 15 - Evolution

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Chapter 15 - Evolution

• Biology
• Mr. Hines

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15.1 The Puzzle of Life.Target 1 - Explain
Biodiversity.

• A. The puzzle of lifes diversity
• B, The earth is filled with millions of different
  life forms.
• C. Life on earth is very diverse and includes
  everything from intelligent beings like humans to
  single celled organisms known as bacteria.
• D. The variety of living things on earth is
  called biodiversity.

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• E. With such diversity on the planet, many
  questions arise.
• F. How did organisms arise?
• G. How are they related?
• H. Questions like these are known as the puzzle
  of lifes diversity.
• I. We will look into this puzzle in this chapter
  according to science.

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Target 2 - Explain the basic idea behind a theory.

• A. Remember that science is based on
  observations.
• B. There is a lot of data which supports the
  theory of evolution most scientists believe
  evolution to be true.
• C. However, the term theory suggests that
  evolution cannot be confirmed as fact.

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• D. Theory well supported testable explanation
  of phenomena that have occurred in the natural
  world.
• E. Therefore, evolution is a theory.

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Target 3 - Define Evolution and give examples.

• A. Evolution is sometimes misunderstood.
• B. Some people think that evolution says that
  monkeys turn into humans Evolution does not say
  this at all.
• C. Evolution is a complex understanding of how
  populations of organisms change of long periods
  of time.
• D. Evolutions most simple definition is CHANGE
  OVER TIME.

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• E. For example, humans were not the same today as
  they were hundreds of thousands of years ago.
• F. Fossil evidence proves this to be true.
• G. Since humans have CHANGED OVER TIME, it shows
  that humans have evolved change over time.
• H. We will look at this in more detail soon?

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Target 4 - Give basic facts about Charles Darwin
and his Voyage of the Beagle.

• A. Charles Darwin contributed most of our
  understanding of Evolution.
• B. We will study the work of Darwin in this
  chapter his name will be mentioned many times.
• C. Darwin sailed a ship called The Beagle
  around the world making many observations (1831)
• D. Most of his work was done on the Galapagos
  Islands west of South America

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• E. During his travels, he made numerous
  observations and collected evidence that led him
  to propose a revolutionary hypothesis about the
  way life changes.
• F. In more recent years, his hypothesis has
  generated enough evidence to become a theory.
• G. Evolution explains every aspect of the puzzle
  of the diversity of life.

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Target 5 - Understand Darwins observations.

• A. Throughout Darwins travels, he collected 68
  different species of beetles he wasnt even
  looking for beetles.
• B. This led him to realize the amazing patterns
  and diversity of life.
• C. Darwin was intrigued by the fact that so many
  plants and animals seemed remarkably well suited
  to whatever environment they inhabited.

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• E. As he traveled from continent to continent, he
  noticed that there were no rabbits in Australia
  and no kangaroos in England.
• F. Why is this since the habitats in both
  continents are similar?

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Target 6 - Understand the connection between
Living organisms and fossils.

• A. Darwin realized that the living organisms were
  just a small part of the puzzle.
• B. As he collected fossils, he realized that most
  of the puzzle was found in the fossil record.
• C. Many organisms in the fossils were very
  different from organisms alive today.

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• D. This indicated that many species died off.
• E. This also indicated that life on Earth is
  different today as it was then.
• F. Many of Darwins discoveries were from the
  Galapagos Islands.

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Target 7 - Describe the diversity of the
Galapagos Islands.

• A. Out of all of the continents Darwin visited,
  he was most influenced by what he saw on the
  Galapagos Islands 800 miles west of South
  America.
• B. Even though the islands were close together,
  each island had a different climate.
• C. Some islands were hot, dry, and barren with
  sparse vegetation

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• D. Others had mountains with lots of vegetation
  and rainfall.
• E. Darwin paid close attention to the giant
  tortoises and ground finches.
• F. He noticed that the tortoises were different
  on each island and suited for the environment.
• G. We will take a closer look at the tortoises
  (big turtles) and finches (birds).

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Target 8 - Compare and Contrast the Tortoises on
three different Galapagos Islands.

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• A. Tortoises on Hood Island
• 1. The vegetation on Hood Island is sparse.
• 2. This tortoise is suited for this environment
  with a long neck to reach higher vegetation and a
  shell that allows it to extend its neck.

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• B. Tortoises on Isabela Island
• 1. The vegetation on Isabella is very abundant
  and closer to the ground.
• 2. The tortoise on this island has a short neck
  and a shell that does not allow it to extend its
  neck

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• C. Tortoises on Pinta Island
• 1. The tortoise on Pinta island has a neck and
  shell intermediate to the other 2 based on its
  habitat.

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Target 9 - Compare and Contrast the different
Finches on the Galapagos Islands.

• A. Now we will take a close look at the finches
  there are 13 species on the Galapagos.B. The
  finches are all about the same size, but their
  beaks are all different.

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• C. Each bird has a different kind of beak which
  is suited for the environment on a specific
  island.
• D. Some of the finches live on an island where
  there is lots of vegetation.
• E. The size of the beak depends on the kinds of
  seeds that are available to them.

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• Look at figure A and draw a Finch below which
  will likely be most adapted to eat small seeds.
• Look at figure A and draw a Finch below which
  will likely be most adapted to eat large seeds.

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• Write a complete sentence about how beak size
  gives a finch a survival advantage.
• __________________________________________________
  _____________________________________

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Target 10 - Describe Darwins final thoughts as
he journeyed home.

• A. As you might imagine, sailing the seas in the
  1800s took a long time.
• B. Darwin had a lot of time to sit around and
  think.
• C. He started to connect the dots about how
  living things were suited for their environment.
• D. He wondered if all of the different species on
  each of the islands were once members of the same
  species.

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• E. In other words, he wondered if one species
  arrived on the island, and over time, they
  changed to adapt to the environment which is
  different on each island.
• F. Was this possible? Can living things change
  over time to adapt to new environments?
• G. If so, it would turn peoples view of the
  natural world upside down.

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15.2 - Ideas that shaped Darwins thinking.

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Target 11 - Understand some older ideas about the
world when Darwin lived.

• A. Darwin lived in a time when the world was
  being explored.
• B. Much of the scientific knowledge that was
  forming was about the earth and living things.

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• C. Some ideas that were changing.
• 1. The earth is flat
• 2. The earth is unchanged from its creation.
• 3. Life was created thousands of years ago.
• 4. Living things are today as they have always
  been.

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• D. In other words, science was proving many old
  ideas to be incorrect.
• E. Science and Religion began to conflict.
  Consider this for thought.
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• Science unanswered questions.
• Religion unquestioned answers.

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• F. As time passes, science answers new questions
  based on current observations.
• G. As we learn more, new questions arise.
• H. For example - As fossil evidence was
  uncovered, humans had to rethink their ideas that
  living things are today as they have always been
  - Humans had to change their thinking.
• I. Fossil evidence supports the fact the living
  things are NOT today as they have always been.

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The skull labeled N is a current human skull. If
you look at older human skulls, they are
different. Fossil evidence demonstrates that
humans have changed over time.

• human Homo sapiens. Older skulls not Homo
  sapiens.

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Target 12 - Explain what fossil evidence supports.

• A. Fossil evidence supports the fact that living
  things are not today as they have always been.
• What does fossil evidence support?

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Target 13 - List and explain the two important
discoveries made by Hutton and Lyell.

• A. Hutton and Lyell made 2 important discoveries
  about the earth.
• The earth is millions of years old.
• The earth changes slowly over time.
• B. These changes involved layers of rock pushing
  up from beneath, forming mountains and valleys
  (earthquakes and volcanoes) this is going on
  right now all over the world (US California).

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• C. Fossils of ancient sea creatures are found at
  the top of mountains How?
• D. Rocks are pushed up from forces beneath the
  Earths crust.
• E. Mountains and valleys are then reshaped by
  wind, rain, heat, and cold, etc. (erosion)
• F. These changes occur very slowly hardly
  noticeable in ones lifetime.

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• G. The earth is always changing this study is
  called Geology.
• H. Geology the study of the changing earth.
• I. Geology proved that the Earth is very old
  4.5 billion years old.
• J. Geology showed that Earth is different from
  its creation.

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Target 14 - Understand the connection between the
changing earth and living things on it.

• A. Darwin was influenced by our understanding of
  geology.
• B. If the earth could change, what about living
  things.
• C. If living things were to change, it would take
  lots of time the earth would have to be very
  old it is.

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Target 15 - Explain Lamarcks Evolution
Hypothesis.

• A. Before the time of Darwin, a naturalist by the
  name of Lamarck proposed that by selective use or
  disuse of organs, animals lose or gain certain
  traits over the course of their lifetime.
• B. These traits could be passed on to offspring
  and could change a species over time.

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• C. This is called Tendency towards perfection by
  use or disuse.
• D. Lamarck claimed that an organism could alter
  the shape of its body by use or disuse.
• E. Was Larmarck correct?

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• Example 1 Did giraffes get long necks by
  stretching towards taller trees ultimately
  producing offspring with longer necks?

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Target 16 - Define Acquired Trait and explain why
it cannot be passed to offspring.

• A. An acquired trait is learned or developed -
  is not part of DNA.
• B. Lamarck proposed that offspring could inherit
  the acquired traits from parents.
• C. This is like saying that a woman who lifts
  weights (acquired trait) and becomes stronger
  will pass on strong genes to her children.

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• D. This is also like saying that a person who
  speaks French will have children who are born
  with the ability to speak French.
• E. Acquired traits cannot be passed to offspring
  not in DNA.

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Target 17 - Evaluate Lamarcks Hypothesis.

• A. Lamarck was incorrect in many ways here are
  two examples.
• 1. Acquired traits are not inheritable.
• 2. Behavior has no effect inheritable traits.
• B. He did however develop the idea that organisms
  do adapt to their environment.
• C. Lamarcks hypothesis was proven to be
  incorrect.

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Target 18 - Explain the ideas of Thomas Malthus.

• A. Darwin was also influenced by the work of
  Economist Thomas Malthus.
• B. Malthus noticed that humans were being born
  faster than they were dying.
• C. This meant that at some point, humans would
  run out of food and living space for everyone.

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• D. For many years, war, disease, famine, helped
  keep this in check.
• E. Darwin applied this idea to plants and animals
  since they reproduce much more quickly than
  humans.
• F. A maple tree can produce thousands of seeds in
  a single summer.
• G. An oyster can produce millions of eggs per
  year.

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• H. If all of the offspring lived, the world would
  be over run.
• I. Since the oceans are not filled with oysters
  and the continents are not covered with maple
  trees, something is preventing all of the
  offspring from living.

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• J. What causes some to live and some to die?
• K. Only the ones that live will be able to
  reproduce.
• L. Is it that the strong survive and therefore
  reproduce?

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