BIOLOGY 1101 SECTION 3004 NAMM 1002 Dr. Cinda P. Scott cpscott@citytech.cuny

1. BIOLOGY 1101 SECTION 3004 NAMM 1002 Dr. Cinda P. Scott cpscott@citytech.cuny.edu

3. Is the variation in gene expression genetically based? 99% DNA sequence similarity

4. Fundulus heteroclitus Evan D’Alessandro

5. Marine Molecular Evolutionary Genomics - Evolution - Ecology - Molecular Biology - Genomics - Genetics - Population Genetics - Marine Biology

6. Future Marine Molecular Evolutionary Genomicist?

7. Charles Darwinb.2/12/1809 (Shrewsbury, England)d.4/19/1882

8. The HMS Beagle

9. Voyage of the Beagle

10. Two Books Aboard

12. video

13. HERESY DISHONOR

16. SECRET NOTEBOOKS

17. Key Question Darwin had: • Why would life branch out into a tree? From reading Malthus, Darwin understood: 1- All species struggle 2- All species compete for existence

18. First Key Idea Darwin theorized that it would be beneficial under the circumstances of competition and struggle to have more “favourable variations that would tend to be preserved…” and to not have “unfavourable ones to be destroyed.” • Charles Darwin autobiography, 1876

19. Competition Winners Losers SURVIVE DIE KEY IDEA #2: COMPETITION DRIVES SPECIES VARIATION

20. 1858 • Darwin presents his work (finally!) to the Linean society • First public airing of his idea that species change and that Natural Selection is a force • Officially published his idea as a paper on Evolution in 1858

21. 1859 • Darwin publishes ‘The Origin of Species’ • Amazing book • A masterpiece of arguments for and against evolution • Evidence and argument • 2 Major ideas from ‘The Origin of Species’

22. IDEA 1 Descent with Modification • “From so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.” • “Several classes of facts …seem to me to proclaim so plainly, that the innumerable species, genera, and families of organic beings, with which this world is peopled, have all descended, each within its own class or group, from common parents and have all been modified in the course of descent.” -- The Origin of Species, Chapter 13

23. “The great tree of life, which fills with its dead and broken branches the crust of the earth, and covers the surface with its ever branching and beautiful ramifications.” - The Origin of Species, Chapter 4 WHAT DID DARWIN MEAN BY THIS? Break out session

24. FOSSILS!!

25. 4 Important Fossil Record Sights 1- Burgess Shale British Columbia 2- Dinosaur National Monument Dinosaur, CO 3- Fossil Butte South West Wyoming 4- La Brea Tar Pits Los Angeles, CA

26. Burgess Shale • Trilobite and Aysheaia Fossils • Date to 505 million years ago (mya) • See pg. 308-309 in your text

27. Dinosaur National Monument • Jurassic aged deposits • Date to 150 mya • Intact full skeletons

28. Fossil Butte • Thousands of fish kills found by rail workers in the ‘horizons’ • Palm tree fossil found (tropical climate) • Dates to 50 mya

29. La Brea Tar Pits • Tar served as a preservative • Hundreds of intact skeletons • Dates to 38,000 years ago

30. Key Facts from Fossils 1- Animal and plant forms have changed 2- Timespan of evolution is IMMENSE 3- Extinction is the fate of most species that have ever existed! 4- Environments in every locale have changed, often drastically so…

31. Fossil Dating • Carbon 14 or 14C- a radioactive isotope • 14C half life is 5,730 years upon which time it turns into nitrogen 14 • Half life- the length of time it takes for half of the radioactive isotope to change into another stable element HOW DOES IT WORK? 1- Organic matter begins with the same amount of 14C 2- Compare 14C radioactivity of fossil to that of modern sample of organic matter 3- Amount of radiation left can be converted to age of the fossil 4- It’s a ratio!

32. Earth’s History/Geologial Timescale Table 18.1 (Chapter 18)

33. Pangea

35. We have to understand earth’s history to understand life’s history

36. Earth’s early atmosphere • 4.6 bya- earth formed after 10 billion years in the making • Volcanic eruptions (dust) • Inorganic chemicals • Carbon Dioxide (CO2) • Water vapor (H2O) • Nitrogen (N2) • Hydrogen (H2) • Methane (CH4) • Hydrogen Sulfide (H2S) • Carbon Monoxide (CO) VERY HOT!

37. The Earth Cools • Organic monomers evolved • HOW? 1- monomers came from outer space 2- monomers came from rxns. in atmosphere 3- monomers came from rxns. at hydrothermal vents

38. Proof for outer space- meteorites slamming into earth (bacteria carried to earth) • Proof for monomers coming from rxns. • Stanley Miller, 1953 • Gases that were thought to be in the earth’s early atmosphere were placed in the apparatus, passed by an energy source (electric spark), and cooled to produce a liquid that could be withdrawn. Chemical analysis found that the liquid contained small organic molecules  monomers for large cellular polymers PRODUCED: Amino Acids Organic Acids

39. Proof for Hydrothermal Vents • NH3 would have been abundant at hydrothermal vents on ocean floor, not in atmosphere (N2 was in atmosphere) • Water seeps through vents at 350 deg. F and spews out iron-nickel sulfides which change N2 to NH3 • Lab test confirmed and amino acids form peptides in presence of iron-nickel sulfides

40. Life’s first Protocell Evolves • Plasma Membrane- separates the living interior from the nonliving exterior • Lipid-protein membrane (Sidney Fox) • Coacervate droplets- can absorb and incorporate substances from the outside solution • Lipids organize into liposomes (found in 1960s) • The Cell • See figure 18.4

41. Lipids from egg yolks placed into water aggregate into microspheres Nutrition of protocell • simple organic molecules served as food • Took in preformed foods or were chemoautotrophic (oxidize H2S) • Natural selection favored cells that could extract energy from carbohydrates to transform ADP ATP

42. Fermentation • Lack of O2 in the atmosphere meant that cells had to rely on fermentation for energy • Glycolysis took millions of years to evolve

43. DOMAINS Bacteria– PROKARYOTES Archaea-- PROKARYOTES Eukarya-- EUKARYOTES

44. APPENDIX B- Tree of Life Prokaryotes • Domains Bacteria and Archaea • Simple structure • No nucleus Eukaryotes (protists, plants, fungi, animals) • Domain Eukarya • Complex cell structure • Nucleus • Organelles, compartmentalized Protists • Any eukaryote that is not a plant, fungus or animal

45. SEE FIGURE 4.6 IN YOUR TEXT, CHPT. 4

46. KINGDOMS • Domains Bacteria and Archaea are still being categorized • Domain Eukarya has 4 Kingdoms: 1- Protists (ex. algae, protozoans, water molds) 2- Plantae (plants, multicellular photosynthetic) 3- Fungi (molds, mushrooms) 4- Animalia (multicellular, injest and process foods)

47. Common Ancestor First CellsBacteria  Archaea  Eukarya

48. HUMAN CORN Domain Kingdom Phylum Class Order Family Genus Species Eukarya Animalia Chordata Mammalia Primates Hominidae Homo Homo sapiens Eukarya Plantae Anthophyta Monocotyledones Commelinales Poaceae Zea Zea mays BIONOMIAL NOMENCLATURE

49. Organization of Life Biosphere Ecosystem Community Population Organism Organ System Organ Tissue Cell Molecule Atom

50. The Last Ice Age • Also referred to as glacial maximum (18-20,000 years ago) • 13,000 years ago (marked end) • Pleistocene Era • Currently in an interglacial period (Holocene) • Next ice age in approx. 2,000 yrs. video