Transcript Plato (427
Do Now 1.Turn in on the farm 2.Who was Darwin and what did he do? Don’t know? GUESS! 3.What mode of inheritance is shown? Write down two to three “things” that pop in your mind when you hear the word: Evolution Pre-Darwinian Thought All organisms are perfect. They will remain unchanged throughout their lives. George Cuvier (1782-1832) Paleontologist Noticed in digging for fossils that there were several layers/levels of Earth. In each level, found organisms that resemble organisms alive today. As he got deeper similarities started to fade. Relative Dating Theory of Catastrophism Each level represents a time of a catastrophe. The fossils that he found are organisms that got wiped out by catastrophe. Organisms that are living, survived. Jean Baptiste Lamarck Curator at a science museum in Paris Compared the living organisms to the fossil collection Found similarities which led him to believe they might have a similar ancestor Theory of Use and Disuse: The parts of the body that an organism uses to survive will become developed and strong. If not used will disappear. Inheritance of Acquired Characteristics: Any trait an organism acquires in its life will be passed on to its offspring. Developed ways to travel to other countries across the ocean Found new areas with organisms NEVER seen before. Charles Darwin Father of Evolution. LOVED nature Medicine Studied Theology; LOVED science Age of 22: Became a naturalist aboard the HMS Beagle Darwin’s Observations variation of traits among similar species - Species found on one island looked different from those on nearby islands - Island species looked different from those on the mainland -Differences seemed well suited to animals’ environment Theory of Natural Selection Survival of the “Fittest”: The best adapted individual will survive and pass on their traits to their offspring Evolution? • Gradual change in a population of organisms over time. Population A group of organisms of one species that interbreed and live in the same place at the same time Principles of Natural Selection 1. OVERPRODUCTION A. More offspring produced than can survive B. Only fraction of offspring survive and reproduce Principles of Natural Selection Because of overproduction COMPETITION! Intraspecific Interspecific Principles of Natural Selection 2. Variation A. No two individuals in a population are identical B. Physical characteristics determined by genes Principles of Natural Selection 3. Adaptation “Survival of the fittest” A. Because of variations some individuals are better able to survive in their environment. B. Those that survive and reproduce have the fittest genetic variations. Principles of Natural Selection 4. Descent with Modification (through natural selection) A. Beneficial genes get passed to offspring Descent with Modification • • Over time favorable adaptations gradually accumulate in a species and unfavorable ones disappear. Eventually the accumulated changes result in a new species. Thomas Maithus “The human population grows faster than the Earth. As a result of this large population, we experience death, starvation, and competition”