Marine botany – Algae– the study of aquatic plants and algae that live in seawater have chlorophyll as their primary photosynthetic pigment of the open ocean and the littoral zone and in brackish and lack a sterile covering of cells around their reproductive waters of estuaries cells Macroalgae Phycology-study of algae - Rhodophyta, Chlorophyta, Ochrophyta Microalgae (Phytoplankton) alga (singular) : “I study Silvetia, the intertidal alga” - Dinophyta , Haptophyta, Ochrophyta algae (plural): “Algae rock my world” Angiosperms algal (adj.): Algal lunch, algal skirt, algal growth rate -Mangroves, Marsh Plants, Seagrasses “algaes” (wrong!) Cyanobacteria 21 22 What are algae? What are algae? • Polyphyletic group = different ancestors, different evolutionary histories A B C D E A B C D E A B C D E A B C D E monophyletic polyphyletic paraphyletic or Algae encompassing various distinctly related groups of clade aquatic photosynthetic eukaryotes & bacteria. 23 24 1 Eukaryota Groups DOMAIN Groups (Kingdom) 1.Bacteria- cyanobacteria 2.Archae Alveolates- dinoflagellates 3.Eukaryota 1. Alveolates- unicellular,plasma membrane supported by Stramenopiles- diatoms, ochrophyta flattened vesicles Rhizaria 2. Stramenopiles- two unequal flagella, chloroplasts 4 Excavates membranes 3. Rhizaria- unicellular amoeboids Plantae- rhodophyta, chlorophyta, seagrasses Amoebozoans 4. Excava tes- unilllicellular fllltflagellates Fungi 5. Plantae- most broadly defined plant group Choanoflagellates Animals 6. Amoebozoans- pseudopods for movement & eating 7. Fungi- heterotrophs with extracellular digestion 8. Choanoflagellates- unicellular withsingle flagella 25 26 9. Animals- multicellular heterotrophs DOMAIN Groups (Kingdom) 1.Bacteria- cyanobacteria (blue green algae) Defining characteristics of Algae: 2.Archae “Algae” Photosynthesis (photoautotrophic, usually), using Chl a as 3.Eukaryotes 1. Alveolates- dinoflagellates primary pigment 2. Stramenopiles- diatoms, ochrophyta BUT: Limited cellular differentiation compared to 3. Rhizaria- unicellular amoeboids terrestrial plants 4. Excavates- unicellular flagellates No “real” vascular system 5. Plantae- rhodophyta, chlorophyta, seagrasses Sex organs unicellular, or all cells capable of reproduction (no sterile layer of cells 6. Amoebozoans- slimemolds surrounding sex organs aka NO FLOWERS) 7. Fungi- heterotrophs with extracellular digestion Much greater diversity of photosynthetic pigments 8. Choanoflagellates- unicellular and life histories 9. Animals- multicellular heterotrophs 27 28 2 Algae show tremendous diversity of A Vascular plant An Alga form, habitat, and lifestyle flower sorus blade stem photo Pete Dal Ferro stipe leaf holdfast roots Thallophyte- plants that lack roots, stems & leaves29 30 Free-living and unattached Gymnodinium – planktonic dinoflagellates Rhodoliths - benthic macroalgae photo: Morgan Bond Found in all bodies of water (freshwater, marine intertidal and subtidal) as well as terrestrial systems with enough moisture31 32 3 Free-living and attached to the substrate Epiphytic Parasitic Postelsia palmaeformis “saxicolous”, or “saxiphytic” Caulerpa taxifolia “psammophtyic” Smithora naiadum on Trentepohlia on 33 Phyllospadix torreyi Monterey Cypress 34 Symbiotic and Endoymbiotic Ecological importance of algae Lichen = close association of an alga and a fungus - Primary production; role in species interactions - Ecosystem engineers: e.g. kelp forests, rhodolith beds, coral Marine: Zooxanthellae in corals, anemonies, reefs = Create structure that defines the habitat type nudibranchs, flatworms Radiolarians, Foramaniferans = ameoba + alga fH2O too!: Zoochlorellae in hydras, sponges, etc.35 36 4 Allochthonous input – external source, not from the same ecosystem Nutrient input into terrestrial systems & deep sea Direct importance of algae to human beings Origin’s of the world’s oil supplies (dinoflagellates,coccolithophores,diatoms) Used in biological and medical research (e.g. Cyanobacteria, Chlamydomonas; fucoids); One product of red algae (e.g. Gelidium, Gigartina) = agar; produces gel at low temperatures, used in gel electrophoresis. (HUGE in genetics) Eaten “as itself” (e.g. nori, Spirulina) Products of algae are everywhere: carrageenan (from red algae) and alginates (from brown algae, e.g. Macrocystis, Laminaria) from polysaccharides in cell walls, act as thickening agents Ice cream, mayonnaise, chocolate milk, soy milk, toothpaste, salad dressings, 37 shaving cream, fertilizers, rubber, paint, hair products 38 Algal Taxonomy Algal Taxonomy Hierarchical system of classification: Hierarchical system of classification: Level: suffix: Level: suffix: example: Domain/Empire Domain Eukaryote Kingdom/Group Kingdom/Group Plantae Phylum/Division -phyta Phylum/Division -phyta Chlorophyta Class -ppyhyceae Class -ppyhyceae Ulvoppyhyceae Order -ales Order -ales Ulvales Family -aceae Family -aceae Ulvaceae Genus Genus Ulva species species fenestrata • King Phillip Came Over For Good Spaghetti • Keep Dishes Clean Or Family Gets Sick 39 40 5 DOMAIN Groups (Kingdom) Algal Taxonomy 1.Bacteria- cyanobacteria (blue green algae) Hierarchical system of classification: 2.Archae 3.Eukaryotes 1. Alveolates- dinoflagellates, coccolithophore Level: suffix: example: Chromista 2. Stramenopiles- diatoms, ochrophyta Domain Eukaryote Kingdom/Group Chromista 3. Rhizaria- unicellular amoeboids Phylum/Division -phyta Ochrophyta Class -ppyhyceae Phaeoppyhyceae 4. Excavates- unicellular flagellates Order -ales Laminariales 5. Plantae- rhodophyta, chlorophyta, seagrasses Family -aceae Alariaceae Genus Egregia 6. Amoebozoans- slimemolds species menziesii 7. Fungi- heterotrophs with extracellular digestion 8. Choanoflagellates- unicellular 41 9. Animals- multicellular heterotrophs 42 Algal Nomenclature- acknowledges the first and last person to describe the species 1753, Linneaus divided all life into two Phyla = Plants and Animals for example: Linnaeus called this Fucus pyriferus; later Within the plants, he recognized renamed Macrocystis pyrifera by Carl Adardh, so: • Cryptogams – hidden gametes…land plants • Thallogams – unspecialized gametes … the algae Macrocystis pyrifera (Linnaeus) Adardh Only three genera originally recognized: Fucus-fleshy Ulva- membranous Conferva- filamentous 43 44 6 -Taxonomy/systematics constantly under revision Division % marine ~# species Cyanophyta (blue-green algae) 8 4,500 - Depending on who you ask, between 50,000 and Rhodophyta (red algae) 98 7,000 Chlorophyta (green algae) 13 6,000 10 million different algal spp! Ochrophyta 16,758 Phaeophyceae (brown algae) 99 2,000 Bacillario/Coscinodiscophyceae(diatoms) 50 12,000 Dinop hy ta (dino flage llat es) 90 3, 000 - Biological species concept? Bryophyta Mosses, liverworts 0 25,000 -Morphology? Vascular plants Ferns, horsetail, club moss 0.1 13,018 - Genetics? Gymnosperms 0 722 Angiosperms 0.09 285,000 45 46 Mastocarpus species complex Petrocelis Mastocarpus papillatus + 2N 2N ‘Petrocelis’ crust (sporophyte) 1N 47 1N fronds 48 (gametophytes) 7 Algal Evolution: Endosymbiotic theory of organelle acquisition: 3.9 bya = Cyanobacteria appear and introduce photosynthesis (L. Margolis) 2.5 bya = Eukaryotes appeared (nuclear envelope and ER thought to come from invagination of plasma membrane) - Heterotrophic eukaryote eats heterotrophic bacteria 1.6 bya = Multicellular algae -Rhodophyta (Red algae) &Chlorophyta (proteobacteria) lead to the (Green algae) formation of mitochondria 900 mya= Dinoflagellates & Invertebrates appear -Heterotroppyhic eukaryote eats a photosynthetic bacteria 490 mya = Phaeophyceae (Brown algae) & land plants & coralline algae & (cyanobacteria) lead to the formation crustaceans & mulluscs of a chloroplast 408mya= Insects & Fish -Bacteria not digested but becomes an organelle 362 mya = Coccolithophores & Amphibians & Reptiles 290mya- Gymnosperms Support of Endosymbiotic Theory 49 -Genetic material of the 2 membranes that surround the50 145 mya = Diatoms & Angiosperms organelle Primary Endosymbiosis: Secondary endosymbiotic events 1. Heterotrophic eukaryote eats photosynthetic bacteria 1. Heterotrophic eukaryote eats (cyanobacterium). photosynthetic eukaryote 2. Results in photosynthetic eukaryote. 2. Nucleus from photosynthetic Chloroplast has 2 membranes eukaryote is lost 3. Chloroplast ends up with 4 mmbmembrane s 51 52 8 Secondary endosymbiotic events Secondary Endosymbiosis: 1. Heterotrophic eukaryote eats 1. Heterotrophic eukaryote eats photosynthetic eukaryote photosynthetic eukaryote 2. Nucleus from photosynthetic 2. Nucleus from photosynthetic eukaryote is lost eukaryote is lost 3. Chloroplast ends up with 4 3. Results in photosynthetic eukaryote. mmbmembrane s Chlorop last has 4 membranes. Tertiary endosymbiotic events occur in dinoflagellates 53 54 Details of Endosymbiotic origins - Loss of plastids What is agreed upon: e.g. Parasitic algae on seaweeds: no pigments, all white ? • Each algal division is a Plocamiocolax = Parasite on Rhodophyte alga Plocamium monophyletic group • Reds and Greens – 1 event-2 membranes • Browns – 2 events- 4 membranes Plocamiocolax on Plocamium Plocamium Adapted From Palmer 2003 55 56 9 Three main divisions (phyla) of seaweeds: - Loss of plastids e.g. Heterotrophic algae Chlorophyta: green algae Toxoplasma gondii = parasite in mammal muscular tissues 1 endosymbiotic event = 2 plastid membranes - Apicomplexan, closely related to dinoflagellates ~1.6bya ~6,000 species, 13% marine Ochrophyta: brown algae & diatoms 2 endosymbiotic events = 4 plastid membranes ~490 mya ~2,000, 99% marine & 12,000, 50% Rhodophyta: red algae 1 endosymbiotic event = 2 plastid membranes ~0.9 bya ~60% of domestic cats are infected; ~7,000, 98% marine toxoplasmosis in pregnant women… caused by an alga! 57 58 Paper Discussion on thursday: Lubchenco and Cubit. 1980. Heteromorphic life histories of certain marine algae as adaptations to variations in herbivory. Ecology 61(3): 676-687 Abstract Introduction Graphs & Figures Methods Results Discussion Sign up for paper you would like to lead. 59 60 10.