Evolution/ Natural Selection/ Decent with Modification

Evolution/Natural Selection/Decent with ModificationChapters 14, 15, 16Evolution SurveyEvolution survey.notebookKey PlayersJean Baptiste Lamarck (1809) Charles Darwin (1859 published)Charles LyellThomas MalthusAlfred WallaceWHO ELSE?ProjectDevelop a timeline showing the Key players/events in either Pre-Darwinian or Modern Evolution/Natural Selection Create a minimum of a 20 date timeline with images and explanations for each datewww.timetoast.comPost to my wiki: biology-tidrick@wikispaces.comDue Wednesay 1/18/12 by 11:59pmDarwinDarwin TimelineDarwins Theory of Natural SelectionTwo main pointsDescent with modificationTraits are passed on to the next generation with slight differences Natural selection (mechanism of evolution)Those with the best traits to survive in the environment pass them on to the next generation Leads to: ADAPTATIONS characteristics that improve an organisms chance for survival/reproduction in that environment

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Darwins Main IdeasOverproductionMore organisms produced than can surviveCompetitionStruggle with-in their species and other species to surviveVariationNot every individual with in a species has the same traitsSpeciationNew species arise only when organisms with new, desired traits remainDarwins Main Ideas

Artificial SelectionBreeding domestic animals and plantsSelect a traitHigher chance offspring will exhibit that traitForce a change in a faster period than naturePesticides & Natural SelectionModeling the spread of Pesticide in a natural populationOnline Activity 14.3PesticidesWhy do some insects survive the initial pesticide spray?When the surviving insects reproduce, will their offspring inherit the protective traits?As pesticide continues to be applied, what happens to the percentage of pesticide-resistant individuals in each new generation?

Natural Selection and Health ScienceRead Section 14.5Why is natural selection important in health science?Use Sickle Cell disease and Antibiotic resistanceAnswer questions on page 319

EvolutionChange over timeGeological evolution changes that occur on the EARTHCharles LyellContinental Drift movement of the Earths Plates (~2cm/yr)Pangea (250 mya) supercontinent: one large land massPangea breaks up (180ya) Evidence: Fossils (similar on coast of S.A. and Africa)Impact on organisms: Developed separately = different adaptationsOrganic EvolutionChange within a population of organisms

EvidenceFossilsGeographical DistributionComparative AnatomyEmbryologyMolecular BiologyFossilsAmberIce PetrificationMoldsCastImprint

Sedimentary RockMost fossils foundFossil Record: chronological collection of lifes remains

Relative DatingCompared based on layer orderCorrelation matching rock layers from one area to anotherIndex Files compare to fossils all over the world (a key)

Four outcrops of rock are examined in different locations of a state. The rock types and the fossils they contain are illustrated in the adjacent diagram. Which fossil would be the best choice to use as an index fossil for these rocks?

Absolute DatingDetermines an actual time frame (#)Radiometric Dating (radioactive dating)Radioactive isotopes elements that do not have a stable nucleus, when they break down they release radiationHalf-life: time required for HALF the atoms of an element to decay to a stable form

Geological Time ScaleOrganizes Earths History based on major eventsEras -> Periods Epochs AgesLong periods of relative stabilityBrief episode of great species loss (mass extinction)Followed by adaptive radiation - surviving organisms become wide spread and more diverse due to new habitatshttp://www.enchantedlearning.com/subjects/Geologictime.html

Early EarthStanely Miller (1953) Simulated Early Earth produced organic moleculesCoacervateLarge protein-like substances (pre-cells)More complex than what has been made in the laboratorySmall organic molecules formed larger organic moleculesAble to reproducePre-cells (have membranes)

StromatolitesSediment, Bacteria/Algae, mucus

Early EarthOparin Heterotroph HypothesisFirst life-like structures were heterotrophsconsumed organic molecules in water around themno oxygen = anaerobicArchae (extremophiles): Prokaryotes- survive in extreme environmental conditions (bacteria-like)cellular respiration produced oxygen; over time changed the atmosphere

Geographical Distributionsimilarities and differences between organisms in different parts of the worldgeographic isolation separation of a population due to geographic changeWhy does geographic isolation not have as great an impact on species such as birds, large mammals (cyotes)?migration

Splinter populations Crucial events in the origin of new speciesWhy?shift in the gene frequency = changing the gene pool = no longer able to reproduce with original population

Bottleneck Effect Random decrease of population, decreases genetic diversityFounder Effect new colony started by a small population

Comparative Anatomy the study of similarities and differences among living thingshomologous structures - parts of different organisms that have similar structures, but different functionsex: human hand, whale fin, bird wing- evolution is a remodeling process: structure become modified and take on new functionsDescent with modification

Comparative Anatomy Analogous structures part of different organism that have different structures, but similar functionsex: bird wing and butterfly wing

Comparative Anatomy Vestigial structures remnants of body parts that were functional in an ancestral formusually reduced in size and have little or no function genes for the smaller size would be favored over 100 vestigial structures in humansex: useless whale hip bones, eye stalks in blind crayfish, embryonic teeth in baleen whales (reabsorb), genes humans defective gene to make vitamin C (most animals can make)diminished use appendix (horse cecum digest plants; may help with immunity), wisdom teeth, coccyx (tail bone), ear muscles

Developmental Similarities

Embryology- studying the development from fertilized egg to fully formed organism Embryological similarities- embryos of closely related species show similar patterns of developmentAll mammals develop pouches on the side of their necks (gill slits) fish/frogs = gill slits, structural differences become clear as development progresses

Homeotic genes control the placement and development of limbs, wings, antennae; a mutation will have a major impact (pg. 333)- Minor changes in genes have subtle changes

Why do the tree dwelling salamanders on pg. 334 develop shorter, more webbed toes than the ground salamanders?

Figure 15-15Compared to the ground-dwelling salamanders' feet (right), the feet of the tree-dwelling salamanders (left) have shorter toes and more webbingan adaptation in the tree salamander's climbing life style.

Molecular Biologysimilarities/differences in the sequences of amino acids of proteins and the DNA codemore similar sequences = more closely relatednew way to test structural hypothesis (whale, hippo, cow, deer, and pig DNA very closely related supports fossils and anatomy)common genetic code shared by all species

42DNA AnalysisCompare segments of beta-casein gene

43DNA AnalysisCompare segments of beta-casein gene

44DNA Differences

45DNA Differences

46DNA DifferencesFewer than five differences2 porpoise & sperm whale3 porpoise & right whale3 sperm whale & right whale3 sperm whale & hippo3 porpoise & hippo3 right whale & hippo3 giraffe & deer3 giraffe & cow4 cow & deer47DNA DifferencesSeven differences7 pigs and peccariesDNA DifferencesRemaining speciesHigher numbers - more distantly related48Phylogenetic Tree - SAMPLEBased on DNA Differences

49Provisional Phylogeny - Cetartiodactyls