MSCI Exam 3
What are the three Domains of life?
Bacteria, Archaea, Eukarya
Energetic Relationships
• Mutualism - both benefit (+/+) • Commensalism - one benefits, one unaffected (+/0) • Parasitism - one benefits, one harmed (+/-) • Host not usually killed • Predation - ones benefits, one consumed (+/-)
Marine Biodiversity: Scientific Bias
• Ocean are big and mostly inaccessibly deep. • Study only what interests us • Scale makes a big difference - bacteria vs whale diversity • Others? • Examples? • But, why should we care about marine biodiversity? • What does it do for us?
Marine Biodiversity
• Oceans have at least 28 Phyla of organisms; land has only 11 • At species level: ~15% species are marine - and most of those are benthic • **Why the discrepancy? 1. Fewer habitats in ocean • → Fewer habitats = fewer niches = fewer species 2. Oceans are much more stable: • → Intermediate Disturbance Hypothesis - goldilocks zone (too much disturbance → colonizers; too little → competitors) 3. Bias
Diurnal Tides
• One high tide; one low tide per day • Northern Gulf of Mexico
Shallow Water Wave Reflection
• When waves hit a solid barrier they are reflected • Reflected at same angle they hit the barrier • If bounce straight back → interference → waves will appear to stand still, rising and falling
Phytoplankton
• ~50% oxygen comes from phytoplankton • Most Common: 1. Diatoms 2. Dinoflagellates 3. Coccolithophorids 4. Cyanobacteria 5. Green algae
Today there is a neap tide. When will be the next spring tide?
1 week
When the moon is at its farthest from Earth, it is known as __.
Apogee
What kind of body coloration would you expect for a fish in a shallow reef habitat?
Colorful
A warty anemone has found itself attached to the shell on the back of a hermit crab. The presence of the anemone helps protect the crab, while the anemone gets scraps a food leftover from the feeding of the hermit crab. What kind of symbiotic relationship is this?
Mutualism
Where would you find a semidiurnal tide pattern in the U.S.?
Myrtle Beach
Which of the following are indicators that a rip current is present at the beach?
a. Foam and debris drifting back to sea in certain areas b. Depressions in the beach perpendicular to the shoreline c. All of these............ d. Areas of reduced wave heights
Which of the following is a reason that the oceans contain fewer described species than land?
a. Much of the oceans is inaccessibly deep and difficult to study. b. All of these are reasons why the oceans have less described species than land........ c. Scientists often only describe what is of interest to them, often overlooking other species that are right in front of them. d. The oceans contain fewer distinct habitats, which means fewer niches e. The oceans are much more stable compared to land.
When two waves are in phase with each other and collide, it is referred to as __.
constructive interference
For very small marine organisms, the viscosity of water is relatively __, making it __ to float.
high; easier
The movement of WATER along a shoreline is referred to as __.
longshore current
The open water zone that exists between high and low tide is called the __ zone.
neritic
When would you observe the absolute highest tidal amplitudes: Moon is in __ Sun is in __ Moon phase is __
perigee; perihelion; full/new
The speed of a deep-water wave is directly related to its __.
period
The benthic zone that gets some sea spray and is usually above the high tide line is called the __ zone.
supralittoral
For capillary waves, the main restoring force is __.
surface tension
What is the best way to escape a rip current?
swim parallel to the shore
The epipelagic zone extends from __ to __.
the surface; 200m
What kind of wave is shown here? ~~~
transverse
Mixed Tides
• 2 high tides and 2 low tides per day • Successive highs/lows are unequal in elevation • West coast U.S. • Caribbean
Semidiurnal Tides
• 2 highs and 2 lows per day • Most common throughout the world • Successive HT/LT's are nearly symmetrical in elevation • East coast U.S.
Conditions for Marine Life: Temperature
• 90% of ocean is between -1 to 4oC • Surface waters more variable: -1-30oC based on latitude, season, etc. • Cold-water animals: psychrophiles - many with cryoprotectants against freezing like DMSP (dimethylsulphoniopropionate)
Plankton
• = anything alive that can't swim against the prevailing current • Phytoplankton - photosynthesize • Zooplankton - anything that isn't phytoplankton; heterotrophs • Bacterioplankton - bacterial plankton • Plankton Size Categories: • Picoplankton - 2-3 microns; 1/100th diameter of human hair; most common phytoplankton is Prochlorococcus - < 1 micron • Nanoplankton - 2-20 microns • Microplankton - aka net plankton; 20-200 microns; easy to catch with plankton net • Macroplankton- 200 microns - 2mm; visible to naked eye • Megaplankton - big stuff; jellies, etc.
Zones of the Ocean: Benthic
• = bottom zones • Supralittoral - splash zone, gets just a little wet; must tolerate high salinities and salt spray • Littoral (intertidal) - between HT and LT; extreme conditions - temperature, salinity, depth, waves, wet/dry, etc. • Sublittoral - below LT to the edge of continental shelf • Bathyal - continental shelf (~ 200m) to 4000m • Abyssal - 4000-6000m • Hadal - below 6000m
Wave Speed
• = celerity = C = wavelength/period = L/T • Once a wave is created, speed may change but period won't • Deep water waves: speed depends on wavelength • Shallow water waves: speed depends on depth
Bioluminescence
• = light generated by an organism (mostly with enzyme luciferase acting on luciferin) Uses: • Predator avoidance - startle or distract predator • Ex: Deep sea shrimp- sticky glowing glue; Copepod - depth charges • → "burglar alarm" - predator becomes prey! • Prey attraction • Ex: angler fish - lure in prey with light • Interesting sex life though.... • Some squids and fish will use photocamouflague - light underneath to blend in with surface • Mate attraction - courtship displays
Thermoregulation
• = maintaining internal temperature within a range • Important because many processes are sensitive to temperature • Endothermic - "warm-blooded", heat generated by metabolism • All mammals & birds; a few fish, reptiles, and insects • Very energetically costly • Benefits? • Ectothermic - "cold-blooded", from environment, not necessarily colder! • Everything else • Low nutritional demands, wider temperature tolerance • Benefits? Costs?
Zones of the Ocean: Pelagic
• = open water zones • Neritic - intertidal, associated with coast • Oceanic - past LT • Epipelagic (aka photic zone) 0-200m - where light penetrates • Mesopelagic -200-1000m • Bathypelagic -1000-4000m • Abyssopelagic - below 4000m
Episodic Waves
• Abnormally high wave • 100ft tall, ½ mile L, 50knots! • Can appear suddenly, unrelated to local conditions • Related to a combination of • Constructive wave interference • Changing water depth • Currents • Hard to study • Not around long • Few survivors...
Deep Wave Dispersion
• As waves move out from a storm center, they get sorted out or dispersed: • Faster ones get further out than slower ones • → can get wave trains - groups of waves of similar T and C • Swells - regular pattern of crests and troughs
Internal Waves
• At boundary of two fluids, like at pycnocline • Cause the boundary to oscillate • L = 100s of m to 1000s of km; T can be several hours! • Caused by: • Low pressure storms - elevates surface and depresses pycnocline, will oscillate as goes back to normal • Currents moving over bottom topography • Propellers - if reach pycnocline, causes "dead water" effect → internal waves drain energy from ship, causing loss of speed
Biological Energy
• Autotrophs - make own organic compounds from inorganic compounds • energy to do it comes from sunlight (photoautotrophs) or chemical energy (chemoautotrophs) • Plants, protists (algae, diatoms, dinoflagellates, etc.), cyanobacteria • Heterotrophs - eat other things to get organic compounds • Everything else • Mixotrophs - do both
Conditions for Marine Life: Inorganic Nutrients
• Autotrophs: need phosphate and N (either NO3 - or NH4 + ); diatoms also need silica • Few nutrients in surface waters - gobbled up by phytoplankton • → shows opposite depth profile as light • How nutrients get to the surface: 1. Runoff from land 2. Upwelling
Tide Pattern Types
• Based on frequency (# per day) and symmetry • 3 types: 1. Semidiurnal 2. Diurnal 3. Mixed
Size: It Really Does Matter
• Bigger animals are less common than smaller ones • Ex: In a bay environment: a few sharks, lots of mullet, tons of plankton • Cells that make up living things are about the same size, no matter how big the organism. Why? • **Size and shape have major effect on ability to transport materials and retain energy • → ***Molecular transport works best with a high surface area: volume ratio (i.e., smaller things) • This is really important in biology
The Surf Zone
• Breakers • Water particle orbital speed slows in the wave trough more than in the wave crest 1. Plungers • Lose energy more quickly, violent crash • Form on narrow, steep beach slopes 2. Spillers • More common, gradual roll • Form over wide, flat beach slopes • Waves curl because they rarely hit the shore exactly parallel → one part of wave leads and breaks first
Conditions for Marine Life: Dissolved Gases
• Carbon dioxide: • Used by autotrophs (photo- and chemo-) to make organic carbon • Heterotrophs use that organic carbon • The biological pump draws carbon dioxide out of the atmosphere and sends it to the deep ocean as organic material • Oxygen - enters ocean via: 1. Photosynthesis 2. Air-sea interactions - surface mixing • Oxygen removed by respiration → oxygen minimum zones ~800m • Less light, but plenty of respiration
Impact of SA:V
• Cell size is linked to SA: V • At the level of the cell, molecular transport is controlled by: • Diffusion (transport of mass) - ex: digestive tract • Greater SA:V = greater transport • Conduction (transport of heat) - ex: large vs small blocks of ice • Greater SA:V = greater heat exchange • Viscosity (transport of momentum) - ex: plankton vs. whale • Greater SA:V = greater resistance to sinking
Classification & Taxonomy
• Classification - putting organisms into groups • Taxonomy - naming them • Taxonomic Hierarchy: Domain → Kingdom → Phylum → Class → Order → Family → Genus → Species • Scientific names: Genus and species • Genus is ALWAYS capitalized and italicized; species is ALWAYS lower case and italicized • Usually tell you something about it, where it's from, who discovered it, famous person, etc. • Ex: Vampyroteuthis infernalis • "Vampire squid from hell"
Wave Interaction
• Constructive interference • Waves are in phase • Waves add constructively and increase wave height • May result in breaking of large waves • Destructive Interference • Waves are out of phase • Waves cancel each other to some extent, smaller wave heights
Two Types of Wind-Generated Waves
• Deep water waves: water is deeper than ½ their wavelength (L) • Shallow water waves: water is shallower than 1/20th their wavelength • Most waves in open ocean are deep-water, become shallow as approach shore
Shallow Water Waves
• Depth < 1/20L - this means the energy extends to bottom and wave becomes affected • Orbits become flattened, wave slows down → reduces wavelength and increases height → until it breaks • Speed is a function of water depth (D): • They all travel at the same speed at a given depth • This means they are non-dispersive
Where would you find a diurnal tide pattern in the U.S.?
Northern Gulf of Mexico
Wave Height
• Determined by: 1. Wind speed 2. Wind duration 3. Fetch - distance over water the wind blows in the same direction • Can have high speed but small fetch = little waves, etc. • Significant wave height = the average wave height of the highest 1/3 of the waves • Where is it highest on the map? • Why? • Largest documented wave: 112ft!
Standing Waves
• Don't propagate; appear to stay still and rise and fall in place • Found in bays, estuaries, and partly enclosed seas • Is a progressive wave reflected back on itself • Nodes (between) vs. antinodes (high/low)
Phylogeny
• Evolutionary relationships among organisms • Use features to distinguish groups and determine evolutionary history • Best to use homologous traits - traits from common ancestry • Ex: All mammals have hair, common ancestor of all mammals had hair • Watch out for analogous traits - not from common ancestry; aka convergent evolution • Ex: Eyes in vertebrates and cephalopods - derived totally independently • Other examples?
Diatoms
• Extremely abundant; ~40% marine primary productivity • Cell wall = frustule, made of silica • Radial (centric) or bilateral (pennate) symmetry • When division occurs, one of the daughter cells gets smaller; eventually sexual reproduction allows the cells to return to the original large size • Useful! • Diatomaceous earth • Filtration • Abrasives, toothpaste
Tide Terminology
• High water: at peak high tide • Low water: at peak low tide • MTL - mean tide level: average height; midpoint of tides • MLT: mean low tide - average level of low tide • Flood tide: tide rising • Ebb tide: tide falling • Slack water: when tides turn; minimal water movement
Distinguish the major groups of zooplankton. Give examples and ecological roles each group plays.
• Holoplankton: • Spend "whole" (get it?) life as plankton • Nearly all phytoplankton, some zooplankton • Most protists, some animals (siphonophores, comb jellies, etc.)incredibly important food source for both small fish such as mackerel • Meroplankton: • Usually spend early life (usually) as plankton, become nekton/benthic later • However, some jellyfish spend early life as benthic, adult as plankton • Many animals (corals, crabs, lobsters, shrimp, molluscs, worms, fish, etc.)they are a dispersal stage for benthic organisms
Wave Reflection: Convex vs. Concave shoreline
• If concave: waves converge and become focused • If convex curve: waves spread
Predicting Tides and Tidal Currents
• Important for shipping, oceanographers, recreation • Can't rely completely on mathematical theory to predict tides → must incorporate the real world • Compare theoretical tide heights to actual local data → can figure out local effects and predict tides • Tide monitoring stations - measure tide levels and flux • But must take measurements for at least 19 years. Why? • Tidal Currents - same idea; use predicted and actual data to determine local effects • Can predict very far in the future and past
Marine Macroalgae
• Large, plantlike algae - don't make flowers • Most are benthic • Some are not: Sargassum • Some are attached but have floats: Kelp
The Tide Cycle
• Lunar day: 24h 50min (takes Earth extra 50 min to "catch up" to moon's new position • Moon orbits in same direction as Earth's rotation • Moon is in tidal lock with Earth - is why we see same side of the moon all the time • Solar day: 23h 56min 5 sec • ~ every 2 weeks Solar and Lunar bulges will align = Full and New moons • = SPRING TIDES - higher high tides; lower low tides • At Quarter moon phases; bulges are perpendicular • = NEAP TIDES - low highs; high lows; smallest tidal range
Variation in Tidal Heights
• Moon doesn't have a perfectly circular orbit - changes declination = angle of moon above/below equator • Declination usually isn't zero = asymmetrical bulges →diurnal inequality • Perigee - when moon is closest • Apogee - moon is farthest away • Perihelion- sun is closest • Aphelion - sun is farthest away • Also affected by: • Continents • Ocean floor topography • Water basin shape • Coriolis
The Tide Wave
• Moon's gravitational attraction vs. friction due to Earth's rotation • Crest of the wave is displaced eastward, ahead of the Moon
Lunar Declination
• Moon's orbital plane oscillates 28½°N & S of the equator • Takes 18.6 years to complete cycle • Water envelope oscillates with it • Creates diurnal and semidiurnal tides
Marine Biological Communities
Often defined by where they live in the water: 1. Open Water: • Plankton - organisms that can't swim against the current • Phytoplankton - photosynthetic plankton • Zooplankton - non-photosynthetic plankton • Bacterioplankton - bacteria in the ocean • Nekton - organisms that can swim against the current 2. On the sea floor: • = Benthic - on, in, or attached to the bottom
When the sun is at its closest distance from Earth, it is known as __.
Perihelion
Conditions for Marine Life: Buoyancy
• = difference between gravity (pulls down) and buoyancy force (pushes up) • If an object weighs more than the weight of water it displaces → sinks • Plankton: • Some store oils (less dense than water) • Many with spines and feathery appendages → increases SA:V → increases viscous force = increased buoyancy • Bigger things: • Some with gas bladders - man-o-war (with CO), Sargassum, kelp, bony fish - swim bladder, sharks - large oily livers
Progressive Wind Waves
• Generated by storms or wind belts • Storm centers - create waves that move outwards in all directions, confusing = "Sea" like "there's a sea building today" • Waves with various L and T
Types of Waves
• Mechanical - require a medium • Water waves (transverse) - we will focus on these • Sound waves (longitudinal) • Electromagnetic - do not require a medium • Visible light • Microwaves • Radio waves • UV • X-rays • Infrared • Gravitational - just proven in 2016! • Ripples in space-time
The Domains of Life
1. Bacteria 2. Archaea 3. Eukarya
Conditions for Marine Life: Salinity
• Most of the ocean ~same salinity, but big changes in coastal waters (especially estuaries) • Osmosis - movement of water from high to low concentrations • "Salt sucks"; "fresh blows" • Saltwater animals constantly fighting dehydration; freshwater constantly needing to pee • What would happen if you put a saltwater fish in freshwater (at the cellular level)? Vice versa? • Some things can go both ways: bull sharks, tarpon, redfish, etc. • Migrations: • Anadromous: spawn in FW, mature in SW - salmon • Catadromous: spawn in SW; mature in FW - American eels • Osmoconformer - body tissues have ~same salinity as environment • Osmoregulator - can regulate it independently • Many fish, estuary crustaceans, mangroves
Variation in Body Temperature
• Poikilotherm - variable body temperature • Homeotherm - ~constant body temperature • Not the same as endo- and ectotherm! • Some ectotherms live where temperature doesn't change (many fish) → temp doesn't vary • Some endotherms let body temperature drop during hibernation or torpor
Tides
• Rise and fall of sea level on coasts • Caused by 2 forces: 1. Gravitational Forces • Depends upon MASS and DISTANCE • Moon is smaller, but much closer than sun • = has greater effect than sun 2. Centripetal Forces • Inertia - liquids "thrown" away from moon/sun • Rotational force • Makes a tidal bulge ~ gravitational one • → 4 tidal bulges: • 2 from moon: gravity and rotational • 2 from sun: gravity and rotational
Coloration
• Some have no color (transparent) - plankton, jellies • Bright colors • Colorful habitat (likes reefs) • Disruptive coloration for confusing predators/prey • Breeding • Dull - stained water/habitat, bottom • Rocks, weeds • Countershading - dark above, light below • Deep - reds, black, or lack of pigment • What is the adaptive value of these coloration patterns in each environment
Rip Currents
• Sometimes the return flow is a fast, concentrated current = rip current • Signs of a rip current: 1. Turbid water (foam, debris, dirty water drifting back to sea) 2. Areas of reduced wave heights 3. Depressions in beach perpendicular to shoreline
Shallow Water Wave Diffraction
• Spread of energy sideways to direction of travel • Waves going through an opening will diffract on other side • If more than one opening, will get interference pattern
Conditions for Marine Life: Light
• Sunlight both heats the oceans and drives photosynthesis • Light only penetrates so deep: • Euphotic zone - enough sunlight for photosynthesis (up to 200m open ocean) • Disphotic zone - can see during day but not enough for photosynthesis • Aphotic zone - no light • Depth of light penetration depends on lots of things: • Angle of solar radiation • Wavelength of light - reds, UV absorbed first; blues last • Amount of "stuff" in the water
Beach Transport & Rip Currents
• Surf zone transport of water is both onto the beach and along the beach • Longshore current - movement of water along shoreline • Longshore transport - movement of sediments, etc. along shoreline
Life in the Ocean
• The ocean is a big place. Really big. • Wide variety of habitats with variable conditions: • Pressure, temperature, salinity, depth, light, etc. • Marine organisms are adapted to live in these places through natural selection - those best adapted to their environment will survive and pass on their genes • Part of evolution - the changing of a population over time • Evolution ≠ Natural Selection • Evolution is a process; natural selection is one mechanism by which evolution can occur (there are several others!)
Tsunamis
• Triggered by seismic activity (strong quakes) • Wavelengths vary from 10 to 500 kilometers! • Periods of up to an hour! • So, would they be shallow-water or deep-water waves when they originate at sea? • Hint: what is the average depth of the oceans? • → they are shallow-water waves! • → their speed depends on depth • → in deep water they can travel up to 500 MPH!
Marine Plants
• Very few. Why? • Seagrasses (only fully marine flowering plant) • Halophytes - salt tolerant plants: • Cordgrass - in marshes • Mangroves: • Red mangrove - prop roots; blocks salt uptake • → water is saltier around roots • Sacrificial leaves • Black mangrove - pneumatophores - like snorkels; exudes salt from leaves • White mangrove - furthest inland • All of these are very important marine nurseries • Places for animals to hide and grow
Tidal Currents
• Water movement associated with tidal flux • Sometimes fast, sometimes slow • Patterns, levels, and currents vary by location • Tidal bore - wall of turbulent water; abrupt change in water level
Deep Water Waves
• Water particles display orbital motion: circular path • Doesn't actually move forward in mathematics; net motion = 0 • They do actually move forward slightly in real life • Energy of a wave (any wave) reaches depth of ½ the wavelength • Orbital motion gets smaller with depth until 1/2L (then, no motion) • Deep water wave speed:
Wave Steepness
• Waves have a maximum height for a given wavelength • Steepness = Height/Length • Smax = 1 / 7 or when the crest angle approaches 120° • If exceeds 1/7, breaks and crashes • Whitecaps - winds build up height fast, then topple over • Common with small waves • Constructive interference can build up waves past critical point, too
Shallow Water Wave Refraction
• Waves refract (bend) when go from deep to shallow • Ever notice how waves "bend" as they approach shore? • Waves almost never hit shore at a right angle • Leading end of wave slows down first, causes wave to bend → ends up parallel to shore (usually) • If shore has headland - energy concentrated there • Or really anything that sticks out • If shore is a bay - energy dispersed
Tide Flow
• When would you observe minimal water flow? • Maximum? • How might this affect marine life? • Adaptations - anatomical, behavioral, physiological?
Tidal Power: Wave of the Future?
• Why not use the tides to generate power? • Dam systems with turbines • Blade-driven "watermills" • Pros: Reliable, predictable, no pollution, simple • Cons: • Very limited locations where it would be feasible • Tidal flux varies (spring vs neap tides) • Very $$ startup • Dams would have large environmental impacts
Assuming a semidiurnal tide pattern, if low tide is right now, approximately when would the next high tide be?
6 hours from now
What determines the height of an ocean wave?
Wind speed, wind duration, and fetch
The crest of the actual tide wave (tidal bulge) is __ the moon
a little ahead of
What are the most common groups of phytoplankton? Describe the features of each and any ecological role each plays.
1. Diatoms • Extremely abundant; ~40% marine primary productivity, their features/ • Cell wall = frustule, made of silica • Radial (centric) or bilateral (pennate) symmetry 2. Dinoflagellates • Cell wall: plates of cellulose (armored) or no plates (naked), • Possess two flagella; strong vertical swimmers, • Most likely to cause harmful algal blooms and bioluminescence • Some are coral symbionts = zooxanthellae, and some contribute to photosynthesis in corals and mollusks 3. Coccolithophorids • Cell wall has plates of calcium carbonate, remove co2 from atmosphere, preserve the composition of the overlying photic-zone 4. Cyanobacteria • Prokaryotic photoautotrophs • AKA blue-green algae • Small, but make ~1/3 primary production in oceans, Can fix nitrogen from atmosphere (N2 → NO3 ) 5. Green algae There are flagellated single cells, multi-cell colonies (some motile), filamentous and attached forms, typically with distinct cell shapes and light green in color. They are the food of other organisms and are important for the climate as they convert carbon dioxide into oxygen by photosynthesis.
How deep does the energy of an ocean wave penetrate?
1/2 the wavelength
When would you observe the smallest tidal amplitudes?
1st and last quarter moon phases
How Waves are Formed
2 Main Forces: 1. Generating - create disturbance on water surface • Lots of different generating forces 2. Restoring - return water to undisturbed state • Gravity (most common) and surface tension (very small waves) • Wind is most common generating force • Creates ripples or capillary waves as moves across surface • For these, restoring force is surface tension • As water gets rougher, easier for wind to grab it → restoring force switches to gravity • Earthquakes, tides, low-pressure systems also generate waves
The mesopelagic zone extends from __ to __.
200m; 1000m
The moon's orbit oscillates between __ degrees North and South of the equator.
28.5
Parts of a Wave
Crest = top; Trough = bottom Wavelength = distance between 2 successive crests (or troughs) Wave height = from crest to trough Wave amplitude = from crest to undisturbed level Wave steepness = height ÷ wavelength Period = time for 2 successive crests to pass a point Frequency = # waves that pass a point per unit time (= 1 ÷ period)
The vertical distance between a wave's crest and trough is its __ .
Height
Say you are watching waves at the beach. You notice that they crash about 50m out, then flatten, then crash again about 5m from shore. What can you say about the bottom topography near the beach?
This could potentially show that there is a sandbar out in the ocean because they crash due to a rise in the shore topography, and build again because of a drop in depth before the shore again.
Explain how tsunamis form. Why are they considered shallow-water waves? What does this mean about their speed of travel in the open ocean? Near the shore?
Tsunamis are caused by seismic activity (strong underground earthquakes). They are considered shallow-water waves because they are barely felt when they are in deep depths, but as they get closer to shore they grow in size. This means that their speed of travel in the open ocean is very fast, but as they approach shore it gets slower.
