Outline of Last LectureOutline of Current LectureEvolutionKey termsEvolutionEcology is both a pattern and a processMisconceptionsScientific explanationsEvolution as a theoryEvidence for the Pattern of EvolutionLecture QuestionHomologyEvidence for evolutionBIO SCI 150 1st Edition Lecture 13Outline of Last Lecture 1. Genetic Technologya. Working with DNAb. Cloning Genesc. Genetic Engineeringd. Clonese. Stem CellsOutline of Current Lecture 1. Evolution a. Key termsb. Evolutioni. Pattern and Processii. Misconceptionsc. Scientific Explanationsd. Evolution as a theoryi. Pattern of EvolutionEvolution *New Professor as of today for the rest of the semester**the class before exams, she will just be asking questions = optional*Most of the exam questions will be “lecture questions”Key termsBiodiversity – two kinds of approaches…- Ecology (the how)o How organisms interact with their environmento Proximate (Immediate) causes of distributionand abundance - Evolution (the why)o How organisms have changed over time o Long-termBiogeography - Distribution of speciesHomology- similarities due to sharing a common ancestor1.4 million different speciesEvolutiono Diversity of organismso Their adaptations and distributiono “Nothing in biology makes senseexcept in the light of evolution” – TheodosiusDobzhanskyEcology is both a pattern and a processEvolution is “descent with modification” Patterno Organisms are related by descent from common ancestorso Organisms have changed over timeProcesso Natural Selection – Charles Darwin o Provided a mechanism to observe scienceMisconceptions- ~50% of Americans do not know what evolution means- ~75% of Americans think evolutionis “unproven” and that it is simply a “theory”o Theories do not become Facts or Laws- they explain themo Laws are well-founded observations of natural phenomena. Scientific explanations1. Be based on evidence from natural processes that can be observed and replicated2. Produce findings or hypotheses that can be confirmed empirically (tested & falsified)3. Be open to debate and changea. Scientific ideas are modifiedi. The idea of the earth being the center of the universe which we now know that the sun is the cent of our solar systemii. Miasma theory of disease (Diseases arise from “bad air”) to Germ Theory of Disease which is still current today but has been modified over the yearsb. Change when new data confront old ideasc. May take hundreds of years to be accepted Evolution as a theory1. Can it make correct predictions?a. Yes, thousands of examples2. Is it usefula. Pesticide resistanceb. ConservationEvidence for the Pattern of Evolution1) Species are related because of common descenta) Biogeography - Distribution of speciesi) Prediction: Species living near each other will be more closely related to each other than they are to species in other areas with the same way of lifeb) Homology- similarities due to sharing a common ancestori) Evolution is a historical process that uses pre-existing variation2) Species have changed through timeConvergence - similarities due to evolution in similar environments- Have similarities but is not as similar as homologyLECTURE QUESTION Homologous traits are similar because…- They result from convergent evolution- They are derived from different ancestors- They are derived from a common ancestor- Their appearance, structure or development is similarHomologyDevelopmental homology – “something that can be viewed in the fossils of certain animals that point to and evolutionary change in their current incarnations”Genetic homology – similar genes control similar developmentEvidence for evolutionSpecies have changed through time- Law of succession- living and fossil species in the same area are similar- Extinctions: Fossil and Recento Species are not perfectly adaptedo 90% of all known species are extincto New species take over- Vestigial traits– left over traitso Pelvis in whaleso Wings in flightless kiwi (the bird not fruit)o Coccyx in human and some ear