Population Genetics and Evolution Unit Review
Biology Note
Charles Darwin and Theory of Evolution
Charles Darwin believed in the theory of evolution and observed variations in tortoises during his trip.
Criteria for Theory of Natural Selection:
Organisms produce more offspring than can survive.
All species have genetic variation.
Competition between species.
Survival of the fittest.
Descent with modification.
Adaptations and Extinction
Adaptations are inherited traits that increase an organism's survivability.
Extinction occurs when a species cannot adapt to a new environment.
Examples of extinct species: dinosaurs, golden black frogs.
Endangered species are on the decline and at risk of extinction.
Examples of endangered species: manatee, giant panda, red fox.
Biodiversity and Speciation
Biodiversity refers to the variations of life forms in an ecosystem.
Extinction level events can decrease biodiversity.
Speciation is the branching of different species from a single species.
Evolution and Paleontology
Evolution is the genetic variation of organisms over time.
Paleontology is the study of fossils and remains.
Fossils found deeper underground are older and more ancient.
Homologous Structures and Vestigial Structures
Homologous structures have similar structures but different functions.
Vestigial structures are present in animals but have reduced or no function.
Example: Whale pelvis.
Embryology and Index Fossils
Embryos of different species may look similar in early stages, indicating a common ancestor.
Index fossils are preserved fossils that leave imprints in rocks or sediments.
Amino Acids and Cladograms
All living things share amino acid triplets.
Some species have more amino acids in common, indicating a closer evolutionary relationship.
Cladograms show the differences between species based on amino acid differences.