5-1 Darwin’s Voyage pages 146-156

Darwin’s Voyage - Darwin’s Theory Charles Darwin sailed on the Beagle, from England to the Galápagos Islands.

EVOLUTION

Map of the Galapagos Island Link

species p 147 a group of similar organisms whose members can mate with one another and produce fertile offspring

species

page 148, figure 2 What difference in the environment do you think might explain the difference in color between the two species of iguanas?

adaptation p 149 a characteristic that helps an organism survive in its environment or reproduce

adaptation

ADAPTATIONS: Organisms in their Environment link

adaptation

EVOLUTION EVOLUTION

page 149, figure 3 What are some other ways these birds might be similar or different that you cannot observe visually?

Darwin's Dangerous Idea Link

Darwin’s Discoveries Video

the gradual change in a species over time evolution p 149 the gradual change in a species over time

evolution

a well-tested concept that explains a wide range of observations scientific theory p 149 a well-tested concept that explains a wide range of observations

scientific theory

Great Transformations LINK

natural selection p 150 the process by which individuals that are better adapted to their environment are more likely to survive and reproduce than other members of the same species

“survival of the fittest” natural selection p 150 “survival of the fittest”

natural selection

EVOLUTION EVOLUTION

Overproduction and Variation - Darwin’s Theory Overproduction and Variation Natural selection is the process by which individuals who are better adapted to their environment are more likely to survive and reproduce than other members of the same species.

Competition and Selection - Darwin’s Theory Competition and Selection Variations among turtles make some of them better able to survive. Turtles that survive to become adults will be able to reproduce.

Relating Cause and Effect - Darwin’s Theory Relating Cause and Effect In a graphic organizer, identify factors that cause natural selection. Causes Overproduction: More offspring are produced than can survive. Variations: Members of the same species differ. Competition: Offspring compete for survival. Effect Natural Selection Selection: Some variations make individuals better fit for survival. Environmental Change: Changes can affect an individual’s survival.( p 154, fig.6) Genes: Genes that help determine survival are passed from parent to offspring.

natural selection

VIDEO: How does evolution work? LINK

VIDEO: Evolution of camouflage LINK

any difference between individuals of the same species variation p 151 any difference between individuals of the same species

variation

Extinction: When Species Die LINK

Theory of Evolution

Video: Why does evolution matter now? Link

End of Section: Darwin’s Theory

Homologous Structures p166 - Evidence of Evolution Homologous Structures p166 The structure of the bones in a dolphin’s flipper, a bird’s wing, and a dog’s leg is similar. Homologous bones are shown in the same color.

A Branching Tree - Evidence of Evolution This branching tree shows how scientists now think that raccoons, lesser pandas, giant pandas, and bears are related.

Kaibab and Abert’s Squirrels - Evidence of Evolution Kaibab and Abert’s Squirrels These two kinds of squirrels have been isolated from one another for a long time. Eventually this isolation may result in two different species.

Identifying Supporting Evidence - Evidence of Evolution Identifying Supporting Evidence Evidence consists of facts that can be confirmed by testing or observation. As you read, identify the evidence that supports the theory of evolution. Write the evidence in a graphic organizer like the one below. Evidence Fossils show that organisms that lived in the past were very different from organisms alive today. Theory Patterns of early development show that some different organisms look similar during their early stages. Evolution Similar body structures in different species show that the organisms shared a common ancestor.

End of Section: Evidence of Evolution

How Do Fossils Form? - The Fossil Record Most fossils form when organisms that die become buried in sediments.

fossil formation

Graphic Organizer Fossil Formation An organism dies in water. The organism is buried under sediment. Over millions of years, the sediments harden and become rock, and the hard parts of the organism are replaced by minerals. The fossil becomes exposed on the surface of a rock.

Why no internal organs?

REVIEW: fossil formation

Earth’s History as a Clock - The Fossil Record Earth’s History as a Clock Fossils found in rock layers tell the history of life on Earth. The history of life can be compared to 12 hours on a clock.

What is the geologic time scale?

Precambrian Time and the Paleozoic Era p162-163 - The Fossil Record Precambrian Time and the Paleozoic Era p162-163

Mesozoic and Cenozoic Eras - The Fossil Record Mesozoic and Cenozoic Eras

Building Vocabulary - The Fossil Record After you read the section, write a definition of each Key Term in your own words. Key Terms: Examples: punctuated equilibria Key Terms: Key Terms: Examples: radioactive element half-life fossil record extinct gradualism Examples: petrified fossil Fossils that form by minerals replacing remains are called petrified fossils. The rocks that fossils are found near contain radioactive elements, which are unstable elements that decay, or break down, into different elements. The theory of punctuated equilibria accounts for the gaps in the fossil record. mold A hollow space in the sediment in the shape of an organism or part of an organism is called a mold. The half-life of a radioactive element is the time it takes for half of the atoms in a sample to decay. cast A cast is a copy of the shape of the organism that made a mold. The millions of fossils that scientists have collected are called the fossil record. relative dating Scientists use relative dating to determine which of two fossils is older. A species is extinct if no members of that species are still alive. radioactive dating A technique called radioactive dating allows scientists to determine the actual age of fossils. Gradualism proposes that evolution occurs slowly but steadily.

End of Section: The Fossil Record

Evolution link

evolution of the elephant