I. _____________________________ a. In science, theories are statements or models that have been tested and confirmed many times. b. Theories have some important properties: i. ______________________ ii. ______________________ iii. ______________________ c. In science, the term “THEORY” does not express doubt. i. ________________________________________ ii. The __________________remains one of the most useful theories in biology because it explains many questions and observations
I. Some questions that can be answered by evolution. a. Why do so many different animals have the same structures, the arm bones in a human are the same bones as a flipper in a whale? b. Why do organisms have structures they no longer use, like the appendix in a human? Non-functioning wings in penguins? c. Why are there bones and fossil evidence of creatures that no longer exist? What happened to these creatures? d. Why do so many organisms’ morphology and anatomy follow the same plan? e. Why is the sequence of DNA similar in some groups of organisms but not in others? f. Why do the embryos of animals look very similar at an early stage?
II. Lamarke’s Theory of ____________________ a. Some thought that you would gain or lose features if you overused or didn’t use them, and you could pass these new traits onto your offspring. i. ____________________________________
• A lizard that didn’t use its legs would eventually not have legs and its offspring wouldn’t have legs. • A giraffe stretched its neck to reach higher leaves, and this stretched neck would be a trait inherited by its offspring. b. Lamarke’s Theory was eventually discarded – ___________________ c. Why? Logically it doesn’t work. Imagine if you were in a car accident and had a leg amputed. This does not mean that your children will only have one leg. Features gained during life are not passed on to children.
III. Darwin’s Theory of Evolution by Natural Selection a. _________________________________________ b. _________________________________________ c. He is famous for his trips to the _____________________, his observations of the finches (and other animals) and the book he wrote: The Origins of Species. i. _______________________________________ ii. Individuals of species will compete for resources (________________) iii. Some __________________ would lead to the death of some individuals while others would survive. iv. _________________________________________________ d. This process he describes came to be known as __________________. e. The favorable variations are called __________________.
IV. Evidence of Evolution a. ________________________ i. If today’s species came from ancient species, then we should be able to find remains of those species that no longer exist. ii. We have tons