BIO100FinalStudyGuide[1] - Chapter 9 Learning the Basics...

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Chapter 9 Learning the Basics The theory of common decent describes that the similarities among living species can be explained as a result of their descent from a common ancestor. Darwin observed that organisms on different islands in the archipelago were similar, but not identical to each other, and were clearly related to each other and to similar organisms on the South American mainland. A vestigial structure/trait is one that has little or no function in an organism but appears to be similar to a more useful structure in other organisms. The process of evolution results in a change in the features of individuals in a population and takes place over the course of generations. In science, a theory is a body of scientifically acceptable general principles. The theory of common descent states that modern organisms descended from a single common ancestor. Domain, Kingdom, Phylum, Class, Order, Family, Genus, species The DNA sequence for the same gene found in several species of mammals is more similar between closely related species and provides evidence for the hypothesis of common descent. Characteristics of a fossil paleontologists use to determine whether it is part of the human evolutionary lineage include: - position of the foramen magnum - structure of the pelvis - structure of the foot The fossil record of hominines dates back at least five million years and indicates the bipedal apes first evolved in Africa.
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Chapter 10 Learning the Basics Fitness is the increased survival and reproduction output of an individual in a population relative to other members of the population. Artificial selection occurs when humans select plants and animals with preferred traits and control the survival and reproduction of these members of the population in order to increase the frequency of those preferred traits. Natural selection occurs when environmental conditions cause one variant to have higher fitness than other variants. Modern organisms descending from a single common ancestor is NOT part of the theory of natural selection. An adaptation is a trait of an organism that increases: - its fitness - its ability to survive and replicate - in frequency in a population over many generations The heritable differences among organisms are a result of: - the differences in their DNA
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This note was uploaded on 09/10/2009 for the course BUS 207 taught by Professor Rhine,s during the Spring '07 term at Waubonsee.

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BIO100FinalStudyGuide[1] - Chapter 9 Learning the Basics...

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