Transcript Chapter 15
Due • Pass to the middle. • Intervention Signatures • Darwin vs. Lamarck • In 30 Seconds they will be late. Warm up 2/4: Make a 2 columns and place the following according to whether they describe Lamarck or Darwin. Place In Two Columns! Working out will make your offspring stronger. If you are strong your offspring might be stronger. The traits that animals desire have nothing to do with how a species adapts and evolves. Survival of the Fittest. Acquired Characteristics. Organisms adapt to the environment through individual change. Organism adapt to the environment because only those with the correct genes survive to reproduce. Chapter 15-1: Charles Darwin Evolution and Natural Selection Ideas Before Darwin • Most people believed that earth was thousands of years old and organisms did not change. • Fossils showed that very different organisms lived in the past. • Jean Baptiste Lamarck proposed the idea of acquired traits to explain the changes. • Traits used most often would be enhanced and passed to offspring • Traits that were not used would diminish and disappear from offspring Charles Darwin • After traveling the world by ship (H.M.S. Beagle) he published The Origin of Species (1858) • Two Goals • Present evidence that evolution occurs • Explain the variety and distribution of organisms on earth Darwin’s Ideas Descent with Modification Darwin’s idea that small changes accumulate over generations. Suggests that all species are descendants from a few kinds of life. Darwin’s Finches – 13 finch species that evidence suggests descended from one original species from Ecuador Population: the number of a specific species living in a specific place at a specific time Natural Selection The mechanism for descent with modification… 4 parts of the theory: 1) Overproduction: Organisms have a large potential to reproduce but are limited by environment & resources 2) Genetic Variation: Individuals vary within a population, and this variation can be passed to offspring. 3) Struggle to Survive: Individuals struggle to survive and some variations benefit the struggle others are a hindrance 4) Differential Reproduction: organisms with the best adaptations will survive the most to reproduce Fitness = a measure of an individual’s hereditary contribution to the next generation Homework •Read p 297-301 •Do problems p 301 # 1-6