Kingdoms Domains 1. Prokaryotes 1a. Archaebacteria Archaea 1b. Eubacteria Bacteria

1. DIVERSITY OF LIFE Current species are classified into 3 Domains and/or 5-6 Kingdoms Kingdoms Domains 1. Prokaryotes 1a. Archaebacteria Archaea 1b. Eubacteria Bacteria 2. Protists Eukarya 3. Plants 4. Fungi 5. Animals

2. Major groups are related All alive today All equally “evolved” But also represent different depths of branching, time since shared common ancestor

3. Diversification also involved a series of innovations that added new forms of life Older modes persisted, possibly largely unchanged “advanced” vs. “primitive”

4. Diverse species appeared then went extinct Current diversity is a slice of a continuing process 3-1

5. Prokaryotes (bacteria) • single celled • DNA, lack nucleus • no organelles • motility, incl. flagella • closest to early life?

6. Prokaryotes No sexual reproduction (meiosis) per se, but various modes of genetic exchange The real “tree” of life?

7. Prokaryotes Much of biochemistry evolved in this group Both respiration and photosynthesis started here __________ (“self feeding”) – use CO2 as carbon source chemoautotroph – energy from chemicals (e.g. H2S) photoautotroph – energy from sun - photosynthesis ___________ (“other feeding”)– use organic molecules for carbon and energy anaerobic – respiration without O2 aerobic – respiration with O2

8. Prokaryotes Cyanobacteria (“blue-green algae”) are free living and photosynthetic contain chlorophyll a, ancestor of __________

9. Prokaryotes Some bacteria and cyanobacteria can also fix ________ In aquatic and terrestrial systems Even in some plant roots Also involved in other Nitrogen transformations (discussed later)

10. Important as ________________ and Pathogens Often closely related species

11. Prokaryotes Archaea – extreme environments – salty, high temperature

12. Prokaryotes “Black smoker” (hydrothermal vent) Archaea – “ancient”, origin of life? http://www.ocean.udel.edu/kiosk/bsmoker.html

13. Eukaryotes – Protists, Plants, Fungi, Animals _________ and Endomembrane Organelles – mitochondria and chloroplasts Sexual reproduction (meiosis) Multicellularity (tissues, organs) Sociality

14. 2. Protists – mostly small, single celled & multicellular - Eukaryotes – true nucleus (containing DNA) and endomembrane - Many are heterotrophs, aquatic – highly diverse - Various parasites (e.g., amoebas, malaria, helminths)

15. Endosymbiotic origin of organelles Mitochondria - ___________ Chloroplast - ___________ Key biochemistry done by bacteria or their descendants

16. Protists Includes true ALGAE – single and multicellular forms that are photosynthetic, and mainly ________(main “producers” in _________ systems) Unicellular algae - contain chloroplasts - chlorophyll a, b, & c

17. Multicellular algae – “___________” - various differentiated structures, food conducting systems - not rooted - holdfast (nutrients from water)

18. Complex life cycles & Sexual Reproduction Both diploid and haploid phases Sexual(meiosis) and asexual (mitosis) components Brown Alga (Laminaria)

19. Green Alga (Ulva) – haploid & diploid equivalent

20. What is Diploid? Haploid? Life cycles often switch between these two states. ___________ are haploid and fuse to form diploid zygotes. The zygote is “diploid” because it contains two complete sets of genes, one “haploid” set from each parent. This means two copies of genes of each gene type (“locus”). The two copies need not be identical (alternate “alleles” are common at each locus)

21. What is Meiosis? Mitosis? When a phase of the life cycle duplicates itself asexually, it is a result of mitosis – the exact copying of the genes.

22. Meiosis Sexual reproduction results from a much stranger process, where the diploid produces haploid cells by meiosis. The genes replicate once, then divide twice, creating (four) cells with only one set of genes each (haploid).

23. Both haploids and diploids can replicate asexually (mitotically) too “Water Mold” (Oomycota) – mostly diploid

24. Malaria (Plasmodium) mostly haploid

25. Recombination – the real point? At least as important as the production of haploid cells, is the recombination of alleles in meiosis. Before making haploid cells, the dividing cells undergoing meiosis essentially “shuffle” the two parental genotypes, creating new genotypes that are mixtures of the parents. Often, the resulting recombinant haploid gametes are fused with gametes from other individuals (___________) to make the zygotes. This creates new genetic variation. The offspring are different from each other and from either parent.

26. Independent assortment Shuffling whole chromosomes (chromosomes = blocks of genes) Crossing over Shuffling genes within chromosomes

28. The paradox of sex - why meiosis? We have emphasized that evolution favors organisms (autocatalysts) that are good at transforming resources into more self – but here is a widespread mode of reproduction that seems designed to create offspring that are different from the parents, that are deliberately NOT self. Why? It is assumed there are good reasons, we just don’t know what they are for sure. But of course there have been many proposed explanations (hypotheses). This is another good example of the difficulty of verifying functional explanations.

29. The Main Contenders 1. a. b. 2. a. b. 3. 4. 5.

30. 3. Plants - primarily terrestrial, multicellular - evolved from ________________ - photosynthetic (chloroplasts), rooted in soil (nutrients) - extensive _____________ tissue - widespread, diverse

31. Mosses and related species

32. Ferns and others

33. Includes tree ferns, once dominant

34. Petro future here Coal Age – Carboniferous 290-360 MYBP

35. How long will current oil supplies last? = _______ years http://www.eia.doe.gov/oiaf/ieo/oil.html

36. Gymnosperms (conifers and others) Ginko Welwitschia Cycad

37. Read Sacks

38. Conifers

39. Angiosperms – flowering plants

40. Include most plants that dominate landscapes today

41. Read Sacks 4. Fungi - eukaryotic, diverse ____________ - unicellular (yeast) and multicelled (mushrooms) - with bacteria, the most important _________ (nutrient releasers) in aquatic and terrestrial systems

42. 4. Fungi - important __________, plant root fungal symbionts that enhance nutrient and water uptake - many fungi are plant & animal pathogens (mostly plants)

43. 4. Fungi- include photosynthetic _______ – a symbiotic association of a fungus and a green algae. Fungus gets carbohydrates for photosynthesis of algae. Live on bare substrate (rock, bark), tolerate drying.

44. Largest organism? Blue Whale Giant sequoia Aspen clone (Populus tremuloides) – one genotype Honey mushroom (Armillaria ostoyae) – one genotype

45. 5. Animals - evolved from ________ - multicellular, heterotrophic eukaryotes - 35 “body plans”, most invertebrates, many marine - highly elaborated tissue and organ systems - herbivores, carnivores, parasites

46. Sponges Jelly Anemone Rotifer Chiton (Mollusk)

47. Scallop (Bivalve) Sea Slug (Gastropod) Sea Star Leech (Annelid) Cephalopods: Nautilus & Octopus

48. Corals - _______________ - have a symbiotic association with “zooxanthellae” which are themselves a symbiosis of a dinoflagellate (protist) and photosynthetic cyanobacteria (prokaryote).

49. Arthropods Trilobite (extinct) Horseshoe Crab Barnacle Lobster Shrimp

50. Trilobite Optics Trilobites developed one of the first advanced visual systems in the animal kingdom. This may have promoted the spectacular diversification of animals. The majority of trilobites bore a pair of compound eyes (made up of many lensed units) Compound eyes in living arthropods such as insects are very sensitive to motion, and it is likely that they were similarly important in predator detection in trilobites. It has also been suggested that stereoscopic vision was provided by closely spaced, but separate eyes http://www.trilobites.info/eyes.htm http://ebiomedia.com/gall/eyes/octopus-insect.html