Marine Biology 178

Mar. 2, 2009              REVIEW LECTURE #--EXAM II

           

II. MARINE ECOLOGY: HIGHER LEVELS OF ORGANIZATION
A. POPULATION--know definition; B. COMMUNITY level--know definition
C. ECOSYSTEM level: regional/habitat communities with all abiotic & biotic components
1. ABIOTIC Components: many, but the essential are:
--a. ENERGY: must be renewed because energy is lost as unusable heat: Energy lost at each food-chain step is 80-90%.

2 PRIMARY forms:
---- i) Solar Light--photosynthesi;s ii) Geochemical--chemosynthesis & reduced mineral energy
-- b. NUTRIENTS & water--not lost but must be recycled through "biogeochemical cycles"!
2. BIOTIC Components: TROPHIC Interactions = Foodwebs ; Terms = Producers, Consumers, Decomposers
-- Know OCEANS vs Land; why complex due to microscopic producers and filter feeders; with 4 or more levels in the oceans often

QUANTITATIVE MEASURES:
1. ABUNDANCE/Productivity--KEY FACTORS are i) Energy & ii) Nutrients--why important! Examples
2. RICHNESS & DIVERSITY: know concept, example of each
-- Spatial Heterogeneity Hypothesis
-- Disturbance Hypothesis! how INTERMEDIATE differs from SEVERE disturbances in affecting diversity
-- Energy-Nutrient Hypothesis: briefly


D. BIOSPHERE level: BIOGEOCHEMICAL CYCLES--Global recycling
5 possible recycling paths: i) Fast Surface loop in mixed layer; ii) Upwelling Loop= sinking and upwelling; iii) deposition then release (from land, oil): iv) Tectonic loop via subduction, uplift -- rock/soil or volcanoes; v) Tectonic loop at ridge --vents, lava
EXAMPLES--Major Ions: recycled via cycles iii) iv) v) including erosion: know basic cation and anion pathways
CARBON: know pathways 1) to iv) including atmospheric CO2 plus limestone, chalk, oil, methane and CaCO3 skeletons/shells
Salt Ions: know pathways for positive and negative major ones

 

III. ORGANISMAL MARINE BIOLOGY-- MARINE LIFE

BASIC ORGANISMAL FEATUREs:

BIOMOLECULES: know basics of DNA and PROTEINS!

METABOLISM: 1)    *PHOTOSYNTHESIS: uses *light and water and CO2  to make sugar and O2 –know equation!

    *CHEMOSYNTHESIS: use mineral/gas energy and hydrogens and CO2 to make sugar and O2 

    2) CONSUMER and 3) DECOMPOSERS: know AEROBIC equation for conversion of sugar and O2 to CO2 and water

TYPES OF ORGANISMS:   Archaea, Bacteria, Eukarya = Protista, Fungi, Plantae, Animalia  -- Know basics of each

*VIRUSES: very common; may kill and thus kill up to 25% of marine plankton

 A. ARCHAEA: 1. Producers using chemosynthesis, usual in extreme habitats—examples

       2. Decomposers

 B. BACTERIA: 1. Producers using chemosynthesis or photosynthesis; for the latter, know CYANOBACTERIA!

       2. Decomposers--may breakdown tough materials like oil, exoskeletal chiton

 C. EUKARYA-- organisms with a true cell nucleus, etc.

    1. PROTISTA: a) Unicellular ALGAE: know DIATOMS (silica 2-part shell) and DINOFLAGELLATES (cellulose armor, 2 flagella).

b) PROTOZOA—animal-like, unicellular: Know FORAMINIFERA (CaCO3 chambered cell, pseudopods for eating)

c) MACROALGAE: RHODO-, CHLORO-, PHAEO-phyta=red, green, brown: know basics of holdfast, stipe, blade; and pneumatocyst in brown algae

    2. FUNGI: decomposers, parasites

    3. PLANTAE: seagrasses, wetlands plants, mangroves

    4. ANIMALIA: feeding types=filter-feeder, deposit feeder, herbivore, scavenger, omnivore, carnivore, [absorber], parasite. KNOW ONES in BOLD CAPS. Can learn just common names of classes

       a. PORIFERA--filterers: small intake, pores and 1 large exit pore; and flagellated cells

       b. CNIDARIA--carnivores: nematocysts, tentacles!! Polyp forms: Hydrozoa (simple)=colonial polyps; Anthozoa (complex)=anemones, corals; Medusa forms: Scyphozoa = jellies; Cubozoa=box jellies

       c. CTENOPHORA= comb jellies; 3 rows cilia; 2 sticky tentacles; carnivores

       d. Platyhelminthes= flatworms carnivores: protrusible pharynx, hard tip stylet

       e. Nemertina=ribbon worms, protusible sticky proboscis wraps prey

       f,. NEMATODA=round worms; many types of feeding; jaws; one of most numerous animals on earth

       g. Echiuroidea=innkeeper worms filterers; proboscis, U-tube

       h. Sipunculida=peanut worms; deposit feeder; sticky tentacles

       i.  ANNELIDA=segmented worm; Class POLYCHAETA--segments/bristles; many feeding types = carnivores with jaws; filter-feeding featherdusters; etc.

       j. Chaetognatha= arrow worms

       k. MOLLUSCA—general: has head/foot; radula, shell.  Features, feeding of classes:

          i) Cl. POLYPLACOPHORA--8-plate shell; herbivores           

          ii) Cl. GASTROPODA--1-piece shell; gone in slugs/nudibranchs; many feeding types

          iii) Cl. BIVALVIA--most filterers using gills; 2-piece hinged shell

          iv) Cl. CEPHALOPODA--radula + beak: carnivores; shelled or reduced or lost shell (octopods)

       l. BRACHIOPODA=lamp shells; filterer (spiral lophophore); clam-like 2-piece shell but has stalk & hole!

       m. Bryozoa=moss animals; filterer (tentacled /ciliated lophophore); zooids more advanced than polyps

       n. ARTHROPODA SubPHYLUM CHELICERATA: Cl PYCNOGONIDA=seaspiders

       o. ARTHROPODA SubPHYLUM CRUSTACEA; 2 pair antenna at front

           i) Cl. COPEPODA=copepods; most numerous animal in oceans; herbivores, carnivores with bristled limbs; swim with antennae

          ii) Cl. CIRRIPEDIA=barnacles; filterers (limbs); head grows to secretes carapace

           iv) DECAPODA= lobster, crab, hermit crab, many shrimp; etc. 5 pairs of limbs; often first pair = claws

       p. ECHINODERMATA—general features of 5x-fold symmetry; endoskeleton+ spines; tube feet

          i) Cl. ASTEROIDEA= seastars: carnivores (stomach evert) ; 5X arms taper from central body

         ii) Cl. ECHINOIDEA=sand dollar, sea urchins; many feeding types; ovoid body, no arms

        iii) Cl. OPHIUROIDEA=brittle and basket stars; deposit feeders 5X arms with distinct joint with body

          iv) Cl. HOLOTHUROIDEA=sea cucumbers; deposit, filter feeders; wormlike body, 5rows tubefeet and soft spines; modified tubefeet for feeding

          v) Cl. Crinoidea--sea lilies; mostly filter-feed

       q. CHORDATA subphylum UROCHORDATA--2-siphon filtering system:  i) Cl. ASCIDEA—tunicate/sea squirt benthic form; 2. Cl. THALIACEA=salps (planktonic form)

       r, CHORDATA subphylum VERTEBRATA: many feeding types: know these classes and their features as given in lecture

          i) AGNATHA; ii) Cl. CHONDRICHTHYES    iii) Cl. OSTEICHTHYES       v) Cl. REPTILIA  vi) Cl. AVES           vii) Cl. MAMMALIA (note AVES=birds are now placed with reptiles!)

 

* ADAPTATION: Interactions of organisms with abiotic/biotic factors lead to adaptation

*Two very different time courses of adaptation:

    1) Within lifetime in individuals (using the genes you have): El Ni–o example! Migratory fish and squid left (adapted with behavior and survived); seals stayed and starved

    2) Evolutionary time between species: new adaptations from natural selection = different genes. EXAMPLE of tropical, polar fish

Theory of Evolution: i) evolution =Change itself and ii) mechanism causing it

Mechanism: Essentials of Natural Selection

---1. Reproduction: Members of a species reproduce, usually more than needed to replace parents;

---2. Variation: Offspring have (semi)random differences in genes due to a) sex and b) mutations and Other Genome changes (some newly discovered)       

            Note genetic diversity is INHERENT in life, not some Platonic flaw. Species with more diversity survive better

---3. "Survival of the fittest" ensues:  in the long run, those with "better" genes will leave more successful offspring, so the "better" genes eventually dominate the species

Species change, diverge over generations since environments (which include other species that are also evolving) change over millenia, so this is a never-ending process!

REAL EXAMPLE: Lake Washington STICKLEBACK fish: how they evolutionarily lost their armor then regained; why armor is a liability in some situations

 

KEY PRINCIPLES of Adaptation

1. Co-evolution: how this causes ongoing adaptations: arms races, etc.. VIDEO example of snail shells and crab claws/fish jaws

2. Cost/benefit tradeoffs:  "Enough but not too much" Principle! EXAMPLES of thick and thin seashells, stickleback armor; SUVs vs sports cars or compact cars

                  Concept that many adaptations cost energy, may divert energy from another adaptation

3. Historical Constraints: leaves non-adaptive vestiges, e.g., whale pelvises. May also be accidents like 6-armed seastar?

 

BENTHIC BIOLOGY and HABITATS

OVERVIEW of Benthic Ecosystems--5 possible food chains in web: Know key examples of each level of each food chain

i) local producer-->herbivore-->carnivore (1 or more levels):

ii) plankton-->local filter feeder--->carnivore (1 or more levels)

iii) detritus-->local deposit/scavenger feeder--->carnivore (1 or more levels)

iv) pelagic animal-->local pelagos-eating benthic carnivore--->carnivore (1 or more levels)

v) local mutualism, e.g. animal/alga partnership -->carnivore (1 or more levels)

 

OVERVIEW of BENTHIC ADAPTATIONS:

Why Movement Factors and Plankton food favor the evolution of sluggish, sessile animals using COST-BENEFIT idea. Thus marine animals are sometimes plantlike! Note how the following adaptations are often analogous to land plant adaptations:

FACTORS and ADAPTATIONS: apply esp. with sluggish/sessile organisms:

1. Light/ENERGY/ Food/Nutrients

Thin and/or Branching structures in filtering animals  [also in algae]=high surface area!

2. BIOTIC interactions --DEFENSES if you canŐt run or fight well

a) ARMOR: coiled shells, light but strong; spines; etc. READING on nacre: brick / beams and mortar microanatomy of mollusc shells!  Recall co-evolution with crushing carnivores! jaws, claws

                  BIOMIMIMETICS/BIOINSPIRATION: practical usages of nacre-like ceramics

b) CAMOUFLAGE: Static anatomy such as flounder; oyster shell

--also can have dynamic/physiological camouflage such as octopod chromatophores--how these work

      ---and dynamic/behavioral camouflage such as decorator crabs

c) TOXINS/Noxious compounds in animals like plants on land;

    i) Anti-Predator: often WARN with bright colors: why?

    ii) Anti-fouling. Anti-competitor compounds: drive off competitors, parasites

    BIOPRODUCTS READING--use on ship hulls? Drugs: why examine marine animals for pharmaceuticals when we usually examine plants on land?

d) Autotomy , self-evisceration: examples of seastars, brittlestars, cucumbers: how useful

e) BEHAVIOR: Clamming up/retreating; etc.; Burrowing as an example; boring in rock

      --ESCAPE RESPONSES: some Sluggish, sessile  animals sometimes have unexpected, fast, innate, predator-triggered maneuvers; e.g., Jumping clam!

3. BIOTIC interactions --OFFENSES

      a) BEHAVIOR    Carnivore Behaviors: ambush; creeping; hunt&chase; sedentary/opportunistic; know example of each

      b) CRUSHING/SMASHING devices - -i) crab claws;  ii) fish jaws; iii) mantis shrimp! Know how each work. BIOMIMETICS: why the interest in mantis shrimp claws?

      c) AMBUSH/GRIPPING weapons: harpooning/paralyzing/stunning/poisoning/suckeringÉ.

 i) Cnidaria nematocysts;  ii) cone snail harpoon; iii) snapping shrimp claw jet burst ; iv) octopods -- suckers . Know how each works!!!  BIOPRODUCTS/BIOMIMETICS: why interest in cone-snail toxins? Suckers?

4. WAVES/CURRENTS: resisting or avoiding

            i) ARMOR

            ii) AVOIDANCE: burrowing, boring..

            iii) BIOLOGICAL GLUES --- how used by MUSSELS: BIOPRODUCTS e.g., mussel glue

5. LIFE-CYCLE Adaptations: r- vs K-selected types: apply cost-benefit idea!

      Modes: a. Asexual (clonal) growth: mutual protection from predation, waves, etc.; and yields rapid colonization

            b. Planktonic Larval Stage=r-strategy: know this lifecycle, outcome, how larvae settle. Few survive

                        --sluggish/sedentary spp need means of DISPERSAL

                        --also ways to RECOLONIZE habitats after destruction of adults

            c. Direct Development: K-strategy; or between r- and K: many fishes, crabs, mammals

             --mobile adults care for eggs, and/or put more energy into young as yolk, milk. Most survive

--young and old both usually mobile enough to disperse readily

      Some are COMBINATIONS, like crabs

 

BENTHIC HABITATS: A. INTERTIDAL

TECTONICS, Surface, Movements:: Basics of Rocky, Sandy, Muddy habitats and wave energy

TECTONICS: Active vs Passive margins -- differences and why

TIDES and WAVES affect many factors ; see below

ROCKY SHORE COMMUNITY: Highest wave energy

ADAPTATIONS to Tide/Wave factors:

      1. Wave Shock--pounding physically by waves, altered by tide level

         a) ARMOR: shells ; b) STREAMLINING

         c) ELASTICITY & energy dissipation; Stipes of Macroalgae! 

         d) GLUES & anchorages: --mussel byssal threads-- READING!!

         e) Behavioral Avoidance—crevices; ŇboringÓ clams

         f) Life-cycle: i)  colonies give mutual protection;   ii) planktonic larvae to recolonize destroyed area

      2. Water availability/loss (evaporation problem):

         a) SHELL,s other waterproof coverings

         b) Physiological "Tolerance"--algae dry up 60-90%;  some chitons 30-70%; unknown how survive,

         c) Behavioral Avoidance--crevices/under algae

         d) Life-cycle: i)  colonies give mutual protection;   ii) planktonic larvae to recolonize destroyed area

      3. Oxygen: gills don't work in air

            a) Lungs—Littorina periwinkle! Isopod scavengers -- both live in upper intertidal

b) Physiological Tolerance: Dormancy & enhanced Anaerobic metabolism=non-acid endproducts (cf. lactic acid in us and other animals)

      4. Temperature -- Pattern: rapid ĆT in sun exposed limpets, barnacles, etc.

            a) COLOR, SHAPE: Reflect/radiate: light-colored and/or sculpted shells; darker to absorb in polar

            b) Physiological Tolerance; how stress or heat-shock proteins might protect upper intertidal organisms

            c) Behavioral Avoidance--crevices/under algae

            d) Life-cycle: planktonic larvae to recolonize

      5. Salinity--drastic changes possible in air: osmosis damage

            a) waterproof coverings again

            b) Physiological:  most exposed spp. killed by major changes, e.g. severe rainstorms

                        i) Osmoregulation --tidepool fish: gills regulate

                    Or ii) Osmoconforming

         c) Behavioral Avoidance--crevices/under algae

         d) Life-cycle: planktonic larvae to recolonize; crucial since major storms can kill off adults.

    6. Nutrients for producers: none when tide out; macroalgae cannot absorb from rocks

            a) MUTUALISM: lichens symbiosis: PO4 from rocks, by fungi; N2 fixation by cyanobacteria --reason for success in splash/upper zones!

    7. Light Intensity: No canopy can develop due to waves

            a) SYMMETRICAL BLADES of macroalgae

            b) SUNSCREENS=UV ABSORBING PIGMENTS: READING on mycosporin amino acids=MAAs

    8. Food/prey availability--none when tide out , so go dormant

                        Exceptions: animals with lungs! i) tidepool animals; ii) Isopods; iii) Littorina periwinkles;  iv) BIRDS: Surf bird adaptation from the video

    9. Predator exposure--more intense in LOWER zones

            a) SHELLS, spines; b) CAMOUFLAGE: e.g., chiton with algae on it

            c) TOXINS, noxious compounds. Example of Phaeophytes--vacuoles w/H2SO4, etc.

            d) Behavioral--avoidance

            e) LifeCycle: as before

    10. Competition:  a) Anti-competitor compounds

            b) Behavioral:  Territoriality--Anemone clone wars  --  acrorhagia battles

                        ii) Farmer LIMPET patrols territory, removes competitors, slams carnivores!

c) LifeCycle --colonize rapidly w/larvae and grow fast

ECOLOGY of ROCKY INTERTIDAL: Factors/Adaptations lead to  ZONATION: be able to draw and explain zones and KITE diagrams of key factors; typical organisms

--Refuge and harsh-environment hypotheses; how this shows that variable abiotic stresses are harder to adapt to in UPPER ZONES; what rewards accrue to succeeders through COMPETITIVE EXCLUSION!!!

  --Intermediate disturbances: role of waves, keystone seastar in enhancing diversity in LOWER zones; prevents Competitive Exclusion

 

 

TEXT: key figures (and associated text, lecture) to understand were given in lecture!

 

READING on LECTURE HANDOUTS--be able to answer these questions:

Lecture #9:      *ARTICLE ON on dumping excess CO2 into the deep-sea floor: how and why?

Lecture #10:    *HOT LIFE-FORMS FOUND: what is the new finding on ocean microbes?

                        *ACID SEAS..affect clownfish how?

Lecture #11:    *SILICON LIFE FORMS: what properties of Diatoms are scientists trying to apply?

                        *PREDATORS RETURN: why might this happen to Antarctica, and why might some life there be vulnerable?

Lecture #12:   *CAN SEAWEED MEND..what is alginate being used for here, and why?

Lecture #13:    *DECODING SEA URCHIN GENOME..found what similarities with human genes?  

Lecture # 14:   *RESEARCHERS DOCUMENT RAPID..what reverse evolution was documented in sticklebacks, and what caused it?

                        *SPINES: what is unusual about sea urchin spines?

Lecture # 15:   *MAKING THE MOST OF IT: What is NACRE made of, and some possible applications (Biomimetics)?

                        *DEEP SEA DENIZEN--what is it about cucumbers that is of practical interest?

                        *DRUGS FROM THE DEEP and PRIMORDIAL OCEAN OOZE: why are researchers seeking drugs in the sea, and with what success?

                        *MANTIS SHRIMP use their specialized limb how?

Lecture # 16:   *SNAIL VENOM: why medically of interest?

                        *SHRIMP SPEWS: how does the snapping shrimp stun its prey?

                        *BIOLOGY REVEALS..what are some applications of marine anchoring mechanisms?

Lecture # 17:   *VIDEO: WOOD GLUE -- how was mussel glue applied here?

                        *ALGINATES, AGAR, CARAGEENAN: are used how?

                        *WARMER SEAS DRIVE..what is global warming doing?

Lecture # 18:   *NATURE's SUNSCREEN: what is this product based on?

                        *ENEMY ANEMONE : why do anemone clones often reach a stalemate in the wild?

                        *FARMER LIMPET--unusual behavior in what ways?

                        *ANEMONE REVEALS..what about its genes?