NameClassDate16.2Ideas That Shaped Darwin’sThinkingLesson ObjectivesIdentify the conclusions drawn by Hutton and Lyell about Earth’s history.Describe Lamarck’s hypothesis of evolution.Describe Malthus’s view of population growth.Explain the role of inherited variation in artificial selection.Lesson SummaryAn Ancient, Changing Earthin Darwin’s day, most Europeans believed that Earthand all its life forms were only a few thousand years old and had not changed very much inthat time. Several scientists who lived around the same time as Darwin began to challengethese ideas. These scientists had an important influence on the development of Darwin’stheory of evolution.Geologists James Hutton and Charles Lyell argued that Earth is many millions of yearsold.They also argued that the processes changing Earth today, like volcanism and erosion, arethe same ones that changed Earth in the past.Knowing that Earth could change over time helped Darwin realize that species might changeas well. Knowing that Earth was very old convinced Darwin that there had been enough timefor life to evolve.Lamarck’s Evolutionary HypothesisJean-Baptiste Lamarck was one of the firstscientists to propose hypotheses about how evolution occurred.To explain evolution, Lamarck hypothesized that all organisms have an inborn drive tobecome more complex and perfect. According to Lamarck, an organism could gain or
Presentation on theme: "Ideas That Shaped Darwin’s Thinking"— Presentation transcript:
1 Ideas That Shaped Darwin’s Thinking
Section 15-2 This section describes the theories of other scientists who influenced Darwin, including Hutton, Lyell, Lamarck, and
Malthus.
2 An Ancient, Changing Earth
Two scientists who helped Darwin and others recognize how old Earth is were ___________and__________ . JAMES HUTTON CHARLES LYELL
3 An Ancient, Changing Earth
Circle the letter of each idea that was proposed by James Hutton. Layers of rock are moved by forces beneath Earth’s surface. Most geological processes operate extremely slowly.
4 An Ancient, Changing Earth
Circle the letter of each sentence that is true about Lyell’s work. His work explained how awesome geological features could be built up or torn down over long periods of time. His publications helped Darwin appreciate the significance of the geological
phenomena that he had observed. He stressed that scientists must explain past events in terms of processes that they can actually observe.
5 An Ancient, Changing Earth
In what two ways did an understanding of geology influence Darwin? Knowing that Earth could
change over time helped Darwin believe that life might change as well. Knowing that Earth was very old assured Darwin that there had been enough time for life to change.
6 Lamarck’s Evolution Hyphotheses
Is the following sentence true or false?
Lamarck was among the first scientists to recognize that living things have changed over time. True
7 Lamarck’s Evolution Hyphotheses
Is the following sentence true or false? Lamarck proposed that all organisms have an innate tendency toward
complexity and perfection. True
8 Lamarck’s Evolution Hyphotheses
How did Lamarck propose that species change over time? Lamarck proposed that by selective use or disuse of organs, organisms acquired or lost certain traits during their
lifetime. These traits could then be passed on to their offspring. Over time, this process led to change in a species.
9 Lamarck’s Evolution Hyphotheses
How did Lamarck pave the way for the work of later biologists? Lamarck was one of the first to
develop scientific hypotheses of evolution and to realize that organisms are adapted to their environments.
10 Lamarck’s Evolution Hyphotheses
Which step in the diagram below shows the inheritance of acquired traits as proposed by Lamarck? Step 3 shows the
inheritance of acquired traits.
11 Population Growth Circle the letter of each sentence that is
true about Thomas Malthus. He was an important influence on Darwin. He believed that war, famine, and disease limit the growth of populations.
12 Population Growth Is the following sentence true or false? The overwhelming majority of a species’ offspring survive.
false