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Make-up. Species Vary Locally. Darwin noticed that difference, yet related, animal species often occupied different habitats within a local area. Good example for this is the Hood island vs. Isabella island tortoise ( galapagos islands). Species Vary over time.
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Species Vary Locally Darwin noticed that difference, yet related, animal species often occupied different habitats within a local area. Good example for this is the Hood island vs. Isabella island tortoise (galapagos islands)
Species Vary over time • Darwin noticed that some fossils of extinct animals were similar to living species.
Applying the BIG idea • You have learned that both Biotic and Abiotic factors affect ecosystems. Give some examples of each, and explain how Biotic and Abiotic factors could have affected the tortoises that Darwin observed on the Galapagos Islands.
16.2 Ideas that shaped Darwin’s thinking Key Questions 1. what did Hutton and Lyell conclude about Earth’s History 2. How did Lamark propose that species evolve 3. What was Malthus’s view of population growth? 4. How is inherited variation used in artificial selection Vocab: 1. Artificial selection
An Ancient changing Earth James Hutton (1726-1797) • Scottish farmer/naturalist • History of the Earth can be determined by understanding present erosion and sedimentation • Founder of Modern Geology • Thought the earth was much older than the accepted 6,000yrs • “Theory of Uniformitarianism”: This was the belief that geological forces at work in the present day—barely noticeable to the human eye, yet immense in their impact—are the same as those that operated in the past. Charles Lyell (1797-1875) • The laws of nature are constant • Erosion/mountains/volcanoes…etc • Theory of Uniformitarianism Summary: This all takes time!!! In order for all this to have happened…the earth is pretty darn old!!!!
“Evolution” Jean-Baptiste Lamarck (1744-1829) • All organisms have an inborn urge to become more complex • Change comes from using them in new ways • Changes during its life would be passed to its offsrping • “acquired characteristics” Problems with Lamarck’s Theory: • No internal drive to better itself • Acquired traits are not passed to offspring ***Significance: He was the 1st to try to explain evolution using the natural process
Population Robert Malthus 1766-1834 “If human population grew unchecked, there wouldn’t be enough living space and food for everyone” Significance to Darwin? 1. This could apply more to other organisms 2. Why hasn’t life run out of space? a. Why do so many die? b. Why do so many live? What does this support?
Artificial and Natural selection • Artificial selection: nature provides the variations, and humans select those they find useful. • How have we practiced “selection” • How could we?
Review • What were Hutton's and Lyell’s ideas about the age of the Earth and the processes that shaped the planet? • How would Hutton and Lyell explain the formation of the grand canyon? • What is an acquired Characteristic? What role did Lamarck think acquired Characteristics played in evolution? • What parts of Lamarck’s hypothesis have been proven wrong? What did he get right? • According to Malthus, what factors limit human population growth? • How did Malthus influence Darwin
16.3 Darwin's case Key Questions: 1. Under what conditions does natural condition occur? 2. What does Darwin’s mechanism for evolution suggest about living and extinct species. Vocab: 1. Adaptation 2. Fitness 3. Natural Selection
16.3 • Adaptation: • Any heritable characteristic that increases an organisms ability to survive and reproduce in its environment • Fitness • How well an organism can survive and reproduce in its environment • Natural selection • Process by which organisms with variations most suited to their local environment survive and leave more offspring.
16.4 evidence of Evolution • Key questions • How does the distribution of species support evolution? • How do fossils support evolution? • How do Homologous structures and embryology support evolution? • What evidence of evolution comes from molecular biology? • What does the Galapagos finches show about natural selection Vocab: • Biogeography • Homologous structure • Analogous structure • Vestigial structure