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Join Charles Darwin on his historic 5-year trip around the world in 1831, where he observed diverse plants and animals, leading to the development of the theory of evolution by natural selection. Explore the Galapagos Islands and learn about the differences in species that sparked Darwin's groundbreaking discoveries, reshaping the scientific understanding of adaptation and genetic evolution. Uncover the process of natural selection, gene evolution, and how new species form, all while unraveling the mysteries of our world's biological diversity.
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Darwin’s Voyage • 5 year trip around the world- 1831 • 22 year old Englishman- • Charles Darwin • Observed plants and animals • Developed the theory of evolution • by natural selection
1835 Galapagos Islands • Diverse group of life forms • Small Islands off the Coast of South America near Ecuador • Differences between organism on island from same species on the mainland were noted
Differences on the Galapagos: • Cormorant- doesn’t fly • Larger claws- on the iguanas to grasp rocks and find food • Finch beaks – many different sizes adapt to food available
EVOLUTION…….. • Define evolution as a gradual change in a species over time- a new scientific theory • Theory- well-tested concept that explains a wide range of observations. • Adaptation- a trait that helps an organism survive and reproduce
1858 Natural Selection- The Origin of Species • Darwin noticed -natural variation (ex. No two zebras have the same stripes) -artificial selection (best crops, best livestock). • He wondered – Did this type of selection happen on its own in nature? • Darwin came up with a possible explanation of how evolution occurs. • He called it natural selection.
Natural Selection- • the process by which individuals that are better adapted to their environment are more likely to survive and reproduce.
Natural Selection cont. • Over a long time, natural selection can modify a population enough to produce a new species • Helpful variations accumulate in a species while unfavorable ones disappear. • Survival of the Sneakiest- http://evolution.berkeley.edu/evolibrary/article/0_0_0/sneakermales_01
GENES in Evolution • Only genes can pass on a trait from parent to offspring • 1977 Finches beaks changed in ONE year due to a drought • Peppered Moth- changed color because of Industrial Revolution
New Species form • When a group of individuals remain separated from the rest of the species long enough to evolve different traits • Pangaea /Continental Drift • Landform isolation- river, mountain, water. (ex. Squirrels of N. Grand Canyon p.155) • Australia