1 / 19

Modern Evolutionary Theory

Modern Evolutionary Theory. What happened after darwin ?. Problems with darwin’s theory. Why is there variation within a species? How are traits passed from one generation to another?.

imaran
Télécharger la présentation

Modern Evolutionary Theory

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Modern Evolutionary Theory What happened after darwin?

  2. Problems with darwin’s theory • Why is there variation within a species? • How are traits passed from one generation to another? http://4.bp.blogspot.com/-EmedhzGoq4U/Tl14PpYybRI/AAAAAAAAgT0/nzHhIdibNw8/s800/101%2Bdalmatians%2Bposter.jpg

  3. Watson and crick’s model of dna structure • genes– portions of the DNA that code for a specific protein • proteins– amino acid sequences that are workhorses of living systems Central Dogma of Molecular Biology DNA  RNA  protein http://www.chemheritage.org/Images/Main-Images-250x290/Discover/Themes/Biomolecules/watson-crick1.jpg

  4. Discovery of the genetic code • series of instructions that shows how proteins are made based on DNA/RNA http://4.bp.blogspot.com/-v3WGNk-6Pps/TxgT9DFFntI/AAAAAAAAGgA/U2ZMO0-Qzjc/s1600/Dna%2Bgenetic%2Bcode%2BUnseen%2BRare.jpg

  5. Sources of inheritable variation • Mutation • any change in DNA sequence • due to • mistakes in DNA replication • environmental factors http://www.brooklyn.cuny.edu/bc/ahp/BioInfo/MUT/Mut.Mutation.html, http://static.ddmcdn.com/gif/evolution-fly.gif

  6. Sources of inheritable variation • 2. Gene shuffling • independent chromosome movement during gamete formation(223~8.4 million gene combinations) • sexual reproduction causes variation within populations • members of a population interbreed and are acted on in similar ways by the environment; they evolve together http://1.bp.blogspot.com/_bAYLalavZ6w/TPtJ5s9xlZI/AAAAAAAAAD0/6KPTjLGRM8g/s1600/meiosis.gif, http://local.brookings.k12.sd.us/biology/Mitosis.htm

  7. http://www.brainbeau.com/cihs/Evolution/Genes_Variation_Genetic_Change_files/slide0066_image020.jpghttp://www.brainbeau.com/cihs/Evolution/Genes_Variation_Genetic_Change_files/slide0066_image020.jpg Evolution as genetic change

  8. Evolution as genetic change http://www.citruscollege.edu/lc/archive/biology/PublishingImages/0306l.jpg

  9. Evolution as genetic change • Natural selection is NOT always necessary for genetic change to occur • Genetic drift • when an allele becomes common in a population by chance • not all characteristics of an organism contribute to its fitness http://biology.unm.edu/ccouncil/Biology_203/Images/PopGen/bottleneck.gif

  10. SpeciationFormation of a new species • species group of organisms that interbreed and produce fertile offspring • reproductive isolation • behavioralisolation • geographic isolation • temporal isolation

  11. http://csmith1974.files.wordpress.com/2010/11/behavioral-isolation-1.jpg, http://bioweb.cs.earlham.edu/9-12/formation/IMAGES/fish.jpg, http://biology-forums.com/gallery/33_14_07_11_5_59_19.jpeg

  12. Experimental evolution • Darwin’s Hypothesis http://4.bp.blogspot.com/-KhUhy5HCFNk/TVb-KjAZtGI/AAAAAAAAAew/f4iTxy9qSE4/s1600/Galapagos-finches.jpg

  13. Experimental evolution • Grant Experiment

  14. Speciation in darwin’s finches

  15. MacroevolutionLarge-scale evolutionary changes that occur over long periods of time

  16. http://mindblowingscience.com/science-by-numbers/the-5-major-mass-extinction-events/http://mindblowingscience.com/science-by-numbers/the-5-major-mass-extinction-events/

  17. MacroevolutionLarge-scale evolutionary changes that occur over long periods of time http://students.washington.edu/kjbyers/coursework.html

  18. MacroevolutionLarge-scale evolutionary changes that occur over long periods of time

  19. http://withfriendship.com/images/i/42351/Punctuated-equilibrium-picture.jpg, http://sciphu.files.wordpress.com/2008/02/punctuated-equilibrium.jpg

More Related