Evidence for Evolution Evidence Supporting Evolution Fossil record Fossil record shows change over timeshows change over time Anatomical record Anatomical

Download Evidence for Evolution Evidence Supporting Evolution Fossil record Fossil record shows change over timeshows change over time Anatomical record Anatomical

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<ul><li><p>Evidence for Evolution </p></li><li><p>Evidence Supporting EvolutionFossil recordshows change over timeAnatomical recordcomparing body structureshomology &amp; vestigial structuresembryology &amp; developmentMolecular recordcomparing protein &amp; DNA sequencesArtificial selectionhuman caused evolution</p></li><li><p>Fossil RecordLayers of rock contain fossils new layers cover older onescreates a record over timefossils show a series of organisms have lived on Earth over a long period of time</p></li><li><p>Fossils Tell A Storythe Earth is oldLife is oldLife on Earth has changed</p></li><li><p>Evolution of BirdsFossil of Archaeopteryxlived about 150 myalinks reptiles &amp; birds Todays organisms descended from ancestral species</p></li><li><p>Land MammalWhere are the intermediate fossils?Ocean MammalSomeones idea of a joke!But the jokes on them!!We found the fossil no joke!</p></li><li><p>Evolution from Sea to Land2006 fossil discovery of early tetrapod4 limbsMissing link from sea to land animals</p></li><li><p>Anatomical RecordOn the outside, animals may look different. , But when you look under the skinIt tells an evolutionary story of common ancestors</p></li><li><p>Anatomical RecordThe same bones under the skinlimbs that perform different functions are built from the same bonesHow could these different organisms have the same bones?</p></li><li><p>Homologous StructuresStructures that come from the same originhomo- = same-logous = informationForelimbs of human, cats, whales, &amp; bats same structureon the insidesame development in embryo different functionson the outsideevidence of common ancestor </p></li><li><p>But Dont Be Fooled By TheseAnalogous structureslook similaron the outsidesame functiondifferent structure &amp; developmenton the insidedifferent originno evolutionary relationshipHow is a bird like a bug?</p></li><li><p>Analogous StructuresDolphins: aquatic mammalFish: aquatic vertebrateboth adapted to life in the seanot closely relatedWatch the tail! </p></li><li><p>Convergent evolution3 groups with wingsDoes this mean they have a recent common ancestor?Flight evolved 3 separate times evolving similar solutions to similar problemsNO! They just came up with the same answer! </p></li><li><p>Convergent evolution led to mimicryWhy do these pairs look so similar?Monarch malepoisonousViceroy maleedibleflybeemothbeeWhich is the fly vs. the bee?Which is the moth vs. the bee?</p></li><li><p>Vestigial organsHind leg bones on whale fossilsWhy would whales have pelvis &amp; leg bones if they were always sea creatures?Because they used to walk on land! </p></li><li><p>Comparative embryologyDevelopment of embryo tells an evolutionary story similar structures during developmentall vertebrate embryos have a gill pouch at one stage of development </p></li><li><p>3. Molecular recordComparing DNA &amp; protein structureeveryone uses the same genetic code! DNAcompare common genescompare common proteinsnumber of amino acids different from human hemoglobin</p></li><li><p>Building family treesClosely related species are branches on the tree coming from a common ancestor</p></li><li><p>4. Artificial selectionHow do we know natural selection can change a population?we can recreate a similar processevolution by human selectiondescendants of wild mustard</p></li><li><p>Selective BreedingHumans create the change over timedescendants of the wolf</p></li><li><p>Artificial Selection gone bad!Unexpected consequences of artificial selectionPesticide resistanceAntibiotic resistance</p></li><li><p>Insecticide resistance </p><p>Spray the field, butinsecticide didnt kill all individualsvariationresistant survivors reproduceresistance is inheritedinsecticide becomes less &amp; less effective</p></li><li><p>Any Questions??</p></li><li><p>Parallel Evolutionfilling similar roles in nature, so have similar adaptationsnot closely related</p></li><li><p>Vestigial organsStructures on modern animals that have no functionremains of structures that were functional in ancestorsevidence of change over timesome snakes &amp; whales have pelvis bones &amp; leg bones of walking ancestorseyes on blind cave fishhuman tail bone</p><p>The avian nature of the brain and inner ear of Archaeopteryx (Alonso et al. 2004) - Archaeopteryx, the earliest known flying bird from the Late Jurassic period, exhibits many shared primitive characters with more basal coelurosaurian dinosaurs (the clade including all theropods more bird-like than Allosaurus), such as teeth, a long bony tail and pinnate feathers. However, Archaeopteryx possessed asymmetrical flight feathers on its wings and tail, together with a wing feather arrangement shared with modern birds. This suggests some degree of powered flight capability but, until now, little was understood about the extent to which its brain and special senses were adapted for flight. Alonso et al. (2004) investigated this problem by computed tomography scanning and three-dimensional reconstruction of the braincase of the London specimen of Archaeopteryx. A reconstruction of the braincase and endocasts of the brain and inner ear suggest that Archaeopteryx closely resembled modern birds in the dominance of the sense of vision and in the possession of expanded auditory and spatial sensory perception in the ear. Alonso et al. (2004) concluded that Archaeopteryx had acquired the derived neurological and structural adaptations necessary for flight. An enlarged forebrain suggests that it had also developed enhanced somatosensory integration with these special senses demanded by a lifestyle involving flying ability.There are innumerable intermediate &amp; transitional formsWhales as land creatures returning to the water.Where are the intermediate forms of whale ancestors?Cartoon making fun of this idea.The cartoons disappeared 10-12 years ago when this fossil was found.</p><p>Ambilocetic natans = Walking whale who likes to swim</p><p>4-5 intermediate forms all found in last 2 decadesIndus River valley in between India &amp; Pakistan.The evolution of resistance to insecticides in hundreds of insect species is a classic example of natural selection in action.The results of application of new insecticide are typically encouraging, killing 99% of the insects.However, the effectiveness of the insecticide becomes less effective in subsequent applications. The few survivors from the early applications of the insecticide are those insects with genes that enable them to resist the chemical attack. Only these resistant individuals reproduce, passing on their resistance to their offspring. In each generation the % of insecticide-resistant individuals increases.</p></li></ul>