Download Teacher`s Guide Galapagos: Beyond Darwin

Galapagos: Beyond Darwin: Teacher’s Guide
Grade Level: 6-8
Curriculum Focus: Plants
Lesson Duration: Two class periods
Program Description
Deep beneath the ocean's surface live creatures Darwin could only have imagined in the 1800s. His
observations were vastly limited by the technology of the times. This video gets you in on a
groundbreaking research project that picks up where Darwin left off.
Onscreen Questions and Activities
Segment 1, Galapagos: Beyond Darwin, Part One
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What was the importance of William Beebe’s expedition to the Galapagos Islands in the 1920s?
(Doctor Beebe’s Galapagos expedition led to the discovery of two species and awakened the public’s
enthusiasm for underwater exploration.)
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What geological event led to the divergent adaptation of marine organisms in the Pacific and
Atlantic Oceans about three million years ago? (Shifting continental plates formed a land bridge
separating the Pacific and Atlantic Oceans, creating two different marine environments for the species
living there.)
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Discuss why island populations are so important to the study of adaptation.
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Activity: Invent an organism that might be found on an isolated island. Describe its
environment then sketch its physical characteristics. Include as many adaptations as possible
and explain the advantage of each of these traits.
Segment 2, Galapagos: Beyond Darwin, Part Two
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What important fossil evidence did barn owls leave behind? (Fossilized owl pellets provide
scientists with a continuous historical record of vertebrate species that populated the Galapagos Islands.)
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What do scientists hope to learn from studying DNA extracted tortoiseshell fossils? (By
comparing the DNA of modern tortoises with that of ancient tortoises, scientists hope to create a record of
genetic change over the past twelve thousand years.)
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Discuss the potential problems associated with removing a specimen from its natural habitat in
order to study it. Why is this ultimately necessary? And how might data be affected?
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Activity: Divide the class into groups. Have each group chose an island to study. Members of
each group should select a specialty, plants, bird, reptiles or marine mammals. Then have each
group create a scientific field guide about its island.
Galapagos: Beyond Darwin: Teacher’s Guide
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Lesson Plan
Student Objectives
Students will understand:
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The term endemic, as applied to animal and plant life, means “native,” or “restricted to certain
geographical areas”
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The presence of introduced species, or animal and plant species not endemic to a certain area,
can endanger endemic species in that area.
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Many unusual animal species are endemic to the Galapagos Islands.
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The presence of introduced animal and plant species in the Galapagos is endangering the
endemic animal and plant populations.
Materials
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Galapagos: Beyond Darwin video and VCR, or DVD and DVD player
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World map clearly showing Galapagos Islands
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Pictures of the Galapagos Islands and of some of the animals endemic to the islands (e.g., giant
tortoises, iguanas, blue-footed boobies)
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Research materials on the Galapagos Islands
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Research materials (e.g., a field guide or materials available from your state department of
agriculture) on plant and animal species in your area
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Computer with Internet access
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Materials needed to create a garden of endemic plants on the school grounds or elsewhere
Procedures
1. Locate the Galapagos Islands on a world map so that students can clearly see where they are
located (in the Pacific Ocean about 600 miles, or 970 kilometers, west of Ecuador).
2. Show students pictures of the Galapagos and of some of the unusual animals that live there,
such as giant tortoises, iguanas, and blue-footed boobies.
3. Review with your students what they know about the Galapagos Islands and their significance.
Be sure they know that Charles Darwin visited the islands in 1835 and studied the animal life
there. He was particularly interested to observe how animal species had adapted, over a long
period of time, to conditions in an isolated part of the world.
4. On the chalkboard, write the terms endemic and introduced. Explain that endemic species of
animals or plants are those that are native to certain geographical areas and restricted to those
Published by Discovery Education. © 2005. All rights reserved.
Galapagos: Beyond Darwin: Teacher’s Guide
3
areas. Tell students that the animals in the pictures they have just seen are endemic to the
Galapagos Islands. Then explain that introduced species are those brought into an area where
they would not naturally exist.
5. Discuss with the class the possible effects of introduced species on endemic species, making the
point that introduced species can actually endanger species endemic to a particular location. For
example, certain introduced plants, also called “invasives,” can take over an area and crowd or
choke out native plants. Another example to consider is an introduced animal species that preys
on endemic animal species or occupies the habitat of endemic species.
6. Go on to explain that, in the Galapagos Islands, introduced species are presently endangering
endemic species.
7. Using research materials such as field guides, help students identify species of plants and
animals endemic to your area. Help students find out what conditions might have allowed
some plants to become endemic. (Your state department of agriculture can be a help.)
8. Have students list as many endemic plants as they can.
9. With the class, use the research students have done to plan a garden of plants endemic to your
area. Plans should include how to keep introduced, or invasive, species out of the garden.
10. As a class project, create an endemic garden on the school grounds or on a nearby available plot
of ground.
Discussion Questions
1. How did Darwin's work aboard the Beagle differ from the way scientists today work aboard the
Steward Johnson?
2. Why are island populations so important in the study of animal adaptation?
3. What significant evidence do sea mounts provide about the history of the animals located today
on the Galapagos Islands?
4. What adaptations must deep-water organisms make as they are brought up for study from the
deep sea environment?
5. What is meant by evolution through natural selection?
6. Many people believe, incorrectly, that the phrase "survival of the fittest" means only the strong
survive. What does "survival of the fittest" really mean?
Assessment
Use the following three-point rubric to evaluate students' work during this lesson.
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3 points: Students are active in class discussions; show a strong understanding of endemic and
introduced species, and the dangers presented by introduced species; identify several species of
plants and animals endemic to your area; work cooperatively in their groups to plan an
endemic garden.
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Galapagos: Beyond Darwin: Teacher’s Guide
4
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2 points: Students participate in class discussions; show a satisfactory understanding of
endemic and introduced species, and the dangers presented by introduced species; identify
some species of plants and animals endemic to your area; work well in their groups to plan an
endemic garden.
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1 point: Students do not participate in class discussions; show a weak understanding of
endemic and introduced species, and the dangers presented by introduced species; identify few
or no species of plants and animals endemic to your area; do not work well in their groups to
plan an endemic garden.
Vocabulary
adaptation
Definition: In biology, the process by which a living organism adjusts to its environment.
Context: Evolutionary adaptation does tend to make species better at surviving.
archipelago
Definition: A group of scattered islands.
Context: This is the newest edition to the Galapagos Islands, as the archipelago itself continues
to grow.
evolution
Definition: The biological theory that existing living organisms have developed from previously
existing organisms through a process of gradual change and modification.
Context: As a paleontologist, he has done extensive work on the evolution of land life on the
Galapagos.
fossil
Definition: The term used to describe the remains of a plant or animal, usually imbedded in the
earth's crust, of a past geologic age.
Context: The tortoise specimen is really important because it is the oldest tortoise fossil found
from the Galapagos.
hot spots
Definition: Volcanic areas where hot magma from the lower mantle of the earth wells upward to
break through the crust of the upper mantle.
Context: The heat is escaping from volcanic hot spots beneath the ocean.
lava tubes
Definition: Volcanic pipes or chimneys made from cooled lava.
Context: Lava tubes are sheltered from the weather and chemically favorable to long-term
preservation of fossils.
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Galapagos: Beyond Darwin: Teacher’s Guide
5
natural selection
Definition: The biological process in which organisms adapt to a changing environment by a
gradual alteration of hereditary characteristics, leading those organisms that successfully
change to increase their chances of survival in succeeding generations.
Context: Through natural selection, marine iguanas separated from the land iguanas and
became a new species.
niche
Definition: A place, position or activity for which a person or organism is best suited.
Context: A specialty provides a competitive advantage or allows them to move into a niche
where less competition exists.
sea mounts
Definition: Underwater mounds rising from the ocean floor.
Context: Geologists found underwater mountains called sea mounts.
species
Definition: A biological classification category comprising related organisms potentially capable
of interbreeding.
Context: Scientists have discovered many new species in the Galapagos.
submersible
Definition: A small, underwater craft often used for deep-sea research.
Context: Scientists made fifty-five deep dives in submersibles.
Academic Standards
National Academy of Sciences
The National Science Education Standards provide guidelines for teaching science as well as a coherent
vision of what it means to be scientifically literate for students in grades K-12. To view the standards,
visit http://books.nap.edu.
This lesson plan addresses the following science standards:
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Life Science: Diversity and adaptations of organisms
Mid-continent Research for Education and Learning (McREL)
McREL's Content Knowledge: A Compendium of Standards and Benchmarks for K-12 Education
addresses 14 content areas. To view the standards and benchmarks, visit
http://www.mcrel.org/compendium/browse.asp.
This lesson plan addresses the following national standards:
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Science—Earth Science: Understands Earth's composition and structure.
Published by Discovery Education. © 2005. All rights reserved.
Galapagos: Beyond Darwin: Teacher’s Guide
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Science—Life Science: Understands biological evolution and the diversity of life.
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Science—Life Science: Understands relationships among organisms and their physical
environment.
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Science—Nature of Science: Understands the nature of scientific knowledge.
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Science—Nature of Science: Understands the nature of scientific inquiry.
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Technology: Understands the relationships among science, technology, society, and the
individual.
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Support Materials
Develop custom worksheets, educational puzzles, online quizzes, and more with the free teaching tools
offered on the Discoveryschool.com Web site. Create and print support materials, or save them to a
Custom Classroom account for future use. To learn more, visit
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http://school.discovery.com/teachingtools/teachingtools.html
Published by Discovery Education. © 2005. All rights reserved.