Quick Notes Bio

Quick Notes Bio - Know Geological Time Scale Grand Canyon...

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Know Geological Time Scale, Grand Canyon, Hominid Tree Examples Modification of pre-existing structure o plants can climb with changes in stems or leaves (vine) Evolutionary trend o head width in the fly genus zygothrica Stasis o trilobites Intermediate forms o theropod dinosaurs o archaeopteryx o sinornis bird o chicken Homologies o limb bones of tetrapods (frogs, lizards, snakes, crocodiles, birds, and mammals) forelimb bones traces back to early tetrapods o Character states of homologous structures may differ in shape bat vs, bird wings fusion or loss of metacarpals (horses) vestigal hind limbs in wales pseudogenes (duplicated genes) reduced limbs in snakes Parallel Evolution o bird wings from dinosaurs, bat wings of bats from mammals individual bones are homologous but not wings bats evolved wings that involved different modifications and traced back to an ancestor that had a forelimb but no wings birds have wings but arose from dinosaurs that didn’t have wings o feeding structures (maxillipeds) in groups of crustaceans o red flowers Humming bird pollen syndrome Convergent Evolution o insect wings (arthropods) vs. bird wings (tetrapods) o vining structure in plants Adaptive Radiation o cichlid fish o silverswords (5mya) o diversification is often related to function
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Lecture 1 Three observations of Darwin Change in Diversity over Time (Descent with modification) Hierarchical organization Good Fit of Organism Environment (adaptation) Evolutionary biology > the how and why Essentialism > Plato Lamarck Proposed that each species originated individually by spontaneous generation from nonliving matter, starting at the bottom of the chain of being. A nervous fluid acts within each species, he said, causing it to progress up the chain. Species originated at different times, so we now see a hierarchy of species because they differ in age Inheritance of acquired traits Species created de novo Transformation Species have not originated from common ancestors Traits arise from use/disuse While shared features, features arose independently During the course life of individuals, its individuals characteristics changed depending on what it needs Darwin Darwin proposed that natural selection that is affected within populations and extended over long periods of time is the process that leaders to diversification > leads to hierarchical system The process of natural selection results in the better fit of organisms to their environment and the origin of new species This theory is a variational theory of change , differing from Lamarck’s transformational theory , in which individual organisms change Two Points o Organisms have descended, with modification, from common ancestors o The chief cause of modification is natural selection acting on hereditary variation. Five Theories
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Quick Notes Bio - Know Geological Time Scale Grand Canyon...

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