Study Guide, Exam 1 Bio

Study Guide, Exam 1 Bio - The Fossil Record: - importance...

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The Fossil Record: - importance of fossils for evolution modern organisms are different from recent fossil organisms, and evolution is the change over time in a populations genetic makeup. - What are fossils? Where are they from? Preserved remnants or impression left by organisms that lived in the past. - Limitations of the Fossil record Fossil record is ordered array in which fossils appear within sedimentary rock, problem is that are in favor of species that had shells or hard skeletons and they are difficult to find. Taxonomy and Systematics - System of classification Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species - Binomial Nomenclature Scientific Name, each individual species has a unique name derived from the genus and the species - How are Species Found, Described, and named? Found by exploring new areas or more carefully looking at the old areas. Described by comparing with species in the same group that are already known Named by the discoverer Phylogenetics - Cladistics: how used and what are limitations? Used for modern phylogenetic systematics, a cladogram is constructed based on characteristics, but does not necessarily reflect true phylogeny ( = evolutionary history) - When is a cladogram a phylogenetic tree? What is a clade? O Clade is ancestral species and all of it descendents - Homology and Analogy with examples Homology: Similarities that are attributable to common ancestry Analogy: Similarities that are attributable to convergence (environmental pressures and natural selection produce similar adaptations) Ex. Two plants that aren’t closely related by have resemblance due to analogous adaptations. Homoplasies, analogous structures that have evolved independently, ex. Wings. - Phylogentic trees –what are they, how are they used, how are they interpreted. What do they not tell you? Used to tell relatedness, relative time, point of divergence of taxa. The problem is that ancestors may no longer exist - Types of Trees and what you can do about it 1. Monophyletic – group is made up of ancestor and all it’s descendents
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2. Paraphyletic – group is made up of an ancestor with some but not all of its descendents, not useful in telling us anything about the evolution of a group 3. Polyphyletic – group lacks the common ancestor that would unite the taxa as a monophyletic group, also not useful in revealing the evolution of a group - Molecular clocks; uses and assumptions Use molecular information to estimate absolute time of evolutionary change Most genetic changes not influenced by natural selection (neutral theory) Rate of genetic change relatively constant and can therefore be calibrated What was the early earth like? -
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This note was uploaded on 04/16/2008 for the course EBIO 1210 taught by Professor Demmig-adam during the Fall '07 term at Colorado.

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Study Guide, Exam 1 Bio - The Fossil Record: - importance...

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