Marine Communities exam 1

Upwellings

-how deep water gets back to the surface -Winds, Coriolis Effect, and friction push surface water away from coast --bottom water replaces surface waters -in some parts of the world, wind runs parallel to the coast. -Surface water gets pushed away from the coast and the deep water comes up to replace it -Some of the worlds biggest fisheries are found in upwelling zones -nutrients increase primary productivity

Why is the Gulf of Mexico a dead zone?

-hypoxia/anoxia are more common in deep waters because it is denser and sinks

Explain the countercurrent exchange system with regard to thermoregulation and oxygen uptake

-in dolphins, heat flows from the arterial (bottom) capillary to the veinus (top) capillary -blood flows out to the fin and cools as it floats out -fins are HIGH SA/V ratio

Impact of all this freshwater: If clam tissue is permeable to water, what happens to salinity of clam blood

-it will drop

Gyres

-large areas with predictable circulation pattern in mid-ocean ---Clockwise rotation in northern hemisphere ---Counter-clockwise rotation in southern

Bays with What Characteristics are Most Prone to Hypoxia?

-large nitrogen and phosphorus levels -elevated nutrients cause large phytoplankton blooms -high oxygen consumption by decaying phytoplankton -warm water -no wind event

Pelagic Zone of the ocean

-layer which includes the free water column or the open-ocean zone DIVISIONS 1.) Epipelagic= 0-200 m down (where most life penetrates) 2.) Mesopelagic= 200-1000 m (if you are here and looked up at the epipelagic, might see some silhouettes) 3.) Bathypelagic= 1000-4000 m 4.) Abyssopelagic= 3,000-6,000 m (total darkness) 5.) Hadal zone= 6,000-11,000 m (deepest part of the ocean) *figure on slide 45 of Ch. 1

If competition exclusion principle is common, then why do so many species coexist? (competitive networks)

4.) Competitive networks: -allow for indirect interactions which allow lots of species to coexist

If competition exclusion principle is common, then why do so many species coexist? (predators)

4.) Predators: -having a species that controls the dominant competitor increases diversity -keystone species

Why the emphasis on CO2?

-even though CO2 only accounts for small portion of atmosphere, it has biggest increase in the greenhouse gases*

Continental Slope

-extends from shelf to deep sea

Describe how BBL affects food limitation for benthic bivalves like mussels, and how the BBL affects fertilization success in sea urchins

-fewer eggs will be washed away before fertilization in sea urchin -Sea urchin wants to release their eggs very low in the benthic boundary so that they will not get carried far away from the current

Abyssal Plain

-flat, featureless plain of deep ocean -most of ocean floor is abyssal in depth -most common habitat on earth

Evidence of rise in CO2 to fossil fuel consumption

-fossil fuels have low C14 (carbon 14) -overtime, its concentration has declined -when you burn fossil fuels, you get more CO2 released than C14 -the increase in CO2 is from burning fossil fuels -Would predict there would be an increase of C12 and C13 and consequently the proportion of C14 in the atmosphere should decrease

Greenhouse effect

-greenhouse gases help move the heat down -traps heat, helps to keep us warm

tophat: If r is positive in an exponential growth model, the population should:

-grow (if r is neg= pop will decline)

surface layer

-has a thermocline or halocline -salt content is more variable

Metapopulation

-different populations of species but are connected through dispersal

Causes of prehistoric climate change- Solar output varies

-11 year sunspots documented (dark, planet-sized regions that appear on the "surface" of the Sun) -Less solar activity about 300 years ago that contributed to ice age

mixed semidiurnal tide

-2 highs and 2 lows of unequal height each day (one might be 12 m, one might be 9 m) -Pacific coast of US -happens within 24 hours and 50 min.

Consequences for marine world

-90% of energy from 1971 - 2010 absorbed by oceans, 1% atmosphere -Increased temp ---Some species live near thermal limits (like corals) -Rising sea level ---Thermal expansion ---Melting land ice -Ocean acidification ---CO2 + H2O + CO32- yields 2HCO3- ---Impedes calcification (Calcium carbonate does not do well in reduced pH) ---Biggest impact on CaCO3 organisms like mollusks, corals, coccolithophores

tophat: Surveys of climate science papers have concluded that ____ of publications support man made climate change.

-97% -climate change is still ongoing

Causes of prehistoric climate change- orientation of continents

-Affected currents , precipitation, etc.

How tide effects intertidal biota:

-Air exposure contributes to desiccation and thermal stress --you are exposed to air and more likely to dry out, that's why a lot of these organisms have shells (snails, etc.) -Respiration and feeding usually occur when submerged -Tidal currents can be strong -Intertidal animals adapted to waves/tides and "feel" tides -Waves/tides dictate activity patterns including feeding and migration, when to reproduce -Larvae often released on spring tides to better disperse (new and full moons) -Tidal locking ---Moon's spin takes one month to complete - same time frame as its revolution around earth ---We only see one side of the moon (called tidal locking) -Longer days ---Tidal forces have slowed earth's rotational velocity

Competition

-All species are capable of exponential growth, but competition limits that growth -Better competitors will survive and produce more offspring -the more fit individuals will have better survival than less fit individuals

Ectotherm

-An animal whose body does not produce much internal heat -cold blooded -maintain a stable body temp behaviorally (marine iguana)

Endotherm

-An organism that is internally warmed by a heat-generating metabolic process -warm blooded -uses body heat to keep warm

tophat: Assume a spring high tide occurs in Newfoundland on April 1 at 8:00 am. -What time and date would you predict the next high tide to be (assume semidiurnal tide)?

-April 1 at 8:25 pm (occurs every 12 hours and 25 min)

tophat: Assume a spring high tide occurs in Mobile, AL on April 1 at 8:00 am. -What is the approximate date of the next spring tide?

-April 15 (14 days later)

tophat: Assume a spring high tide occurs in Mobile, AL on April 1 at 8:00 am. -What time and date would you predict the next high tide to be (assume diurnal tide)?

-April 2 at 8:50 am (low tide is 12 hr 25 min, then high tide is another 12 hours and 25 min)

tophat: Assume a spring high tide occurs in Mobile, AL on April 1 at 8:00 am. -What is the approximate date of the next neap tide?

-April 8 (7 days later)

Factors that influence population size (N)

-Births (+) -Deaths (-) -Immigration (+) -Emigration (-)

Great ocean conveyor (thermohalocline circulation)

-Blue paths represent deep-water currents, while red paths represent surface currents -warm surface water comes through the conveyor belt and sinks -used to understand climate -slide 34 on Ch 2 part 1

Temporal (time-related) changes in atmospheric CO2

-CO2 varies -Big increase in CO2 from now back to 1950 -Can get samples from drilling ice -CO2 levels have reached 400ppm or 0.04% of atmosphere*

Successsion

-Community composition can change over time due to external conditions

Dead Zone

-Deep water HYPOXIA (deficiency in oxygen) -caused by excessive nutrient pollution from human activities that deplete the oxygen required to support most marine life in bottom and near-bottom water

Impact of density

-Denser water "sinks"; less dense water "floats" -Density INCREASES with INCREASING SALINITY -Density DECREASES with INCREASING TEMP (warm water is less dense than cold water, so it will float on top of the cold water) -Density drives physical conditions in water that affect mixing*

Ocean circulation

-Differential heating of earth's surface causes air circulations and climate patterns -also affects evaporation patterns -warm moist air is rising all around the equator -most of the world's deserts are located around 30 degrees latitude

Direct effects of flow

-Distribution may be altered --Dislodgment during high flow, storm surges etc. --plankton can't swim against currents -Suspension feeders move water to gain food --rely on movement of water to get food (jellyfish) -Nekton swim in water --can swim against the current and their shape help reduce drag -Organism design greatly influenced by water movement -tidal currents even in the deep sea do this too

Causes of prehistoric climate change - Milankovitch cycles

-Earth's orbit varies as does the tilt of its axis -degree of orbit affects the seasons -Occur over periods of 100K, 41K, and 26K years 1.) Eccentricity orbit shape (100,000 years) 2.) Obliquity degree of tilt (41,000 years) 3.) Precession - wobble (26,000 years) -The intensity of solar radiation reaching Earth changes, accentuating seasonal variation and resulting in climatic change -Hypothesized that if there is a match with all of these you can get ice age

Benthic Boundary Layer

-Frictional drag exerted by the bed slows flow near seafloor --Friction between the water and the sediment surface causing water to move slowly -The distance above the bed affected by friction drag is the benthic boundary layer --depth at which water has been slowed down -Flow may change from turbulent to laminar --flow rates reduced to near 0 in the bbl -important to larval dispersal -as the water is moving to the right, there is friction between the water and the surface, which slows the water down -water moves slower in bbl

Photosynthesis, respiration, and depth

-Going to have less phytoplankton deeper than on the surface; -Light intensity drops by 90% in less than 10 meters -As we move into deeper water, lot less organic matter -below the epipelagic, we have lost light and photosynthesis -as we move into deeper water, we have a lot less organic matter; there is less oxygen being used up below

What two forces create tides?

-Gravity from the sun and moon pull the water -The earth and moon rotate creating CENTRIFUGAL FORCES (forces that rotate) -Earth and moon act as one system with common center of gravity (offset from the center of the earth)

Poikilotherms

-don't thermo-regulate -when temps outside drop, their body temperatures drop -all invertebrates are poikilotherms

semi-diurnal tide

-Having two high tides and two low tides each day -tide comes about 50 min. later each day -12 h 25 min from one high tide to the next high tide -If high tide is at noon on Tuesday, high tide will be at 12:25 am and 12:50 pm on Wednesday -the sea surface increases for about 6 hr and 35 min hours before it begins to fall (from low to high is 6 hr and 25 min). -most common -occurs in Atlantic coast of US -high tides and low tides are about the same amplitude

SA/V ratios (surface area/volume)

-Heat exchanges with the environment more easily with higher SA/V ratios --Less stable -Dissolved oxygen diffuses more easily with high SA/V -examples: Depends on shape of organism --dissolved oxygen can diffuse from water into the tissue more easily in jellyfish --baby dolphins have a less stable body temp than the mom because it is smaller, the mom body temp is more stable; it heats up or cools off slower than the baby --Worm will cool faster and it will warm faster because worm has less stable body temp (higher surface area to volume less stable) --The urchin has a more stable body temp. (its shape gives it a lower surface area to volume)

Bottom water hypoxia

-Hypoxia and even anoxia (total absense of O2) possible in bottom waters mostly on shallow shelf and bays -Hypoxia is stressful/fatal to multicellular animals -shallow seas are stratified so there is no way to replenish bottom-water oxygen -Bacterial demand for oxygen for cellular respiration is high, reducing oxygen content

Competition graph

-If the X-axis is a limiting resource, then competition occurs - Intraspecific and interspecific competition can limit growth -Intensity of intraspecific competition increases with density -Greater overlap means greater competition What can we infer from these curves? 1) competition in area of overlap 2) greater overlap between species means greater competition

Ecology and evolution

-Interactions between organisms and their environment has occurred as long as there have been organisms -Evolution is the result of previous ecological interactions -Modern interactions are influenced by evolutionary history --Polar bears are only in the arctic due to brown bears evolutionary history only in the northern hemisphere --Penguins are only found in the antarctic

Why is the deep ocean (below mesopelagic) rarely hypoxic?

-Large-scale circulation patterns bring cold, oxygen-rich water to abyssal zone -Metabolic rates in the deep sea is lower due to temperature and more of lower metabolic rate due to food supply -Less organic matter in the deep sea, So less oxygen is consumed in the deep sea -metabolic rates in the deep are very low, leads to reduced consumption of oxygen

Albedo

-Light colors reflect heat -Dark attract heat -White ice sheets melt into blue ocean -As albedo decreases, less heat is reflected and temp is warmer

Mortality and temperature

-Most living things function best from 0-30 degrees C -Cold death occurs when water in cells freezes -Death may also be due to enzyme function (too cold or too hot) --enzyme function depends on temperature -Heat shock proteins prevent denaturing (in high, warm climates) -At high temps, coral bleaching can occur --When corals get too hot they expel their algae and look white called bleaching

Pattern between centrifugal forces and tides

-On side of earth closest to moon, net attractive force (G > C). =HIGH TIDE -On side of earth away from moon, net centrifugal force (C > G)= HIGH TIDE -in between, no net forces, water is pulled away= LOW TIDE

Ecological Consequences of Climate Change

-Other populations might be able to move north or south -Some will adapt and some will not and those who cant may experience local population extinction or entire species extinction -If we stopped emitting greenhouse gases today, earth would warm by 0.5-1 degree C - "warming commitment"

Causes of prehistoric climate change- aerosols

-Particles that reflect solar radiation -Volcanic eruption 1816 "The Year without a Summer" (snowed in northeast US in June) - has a cooling effect

Life at a low Re

-Phytoplankton denser than seawater sink rapidly when nutrients depleted -Can larvae select settling sites? --Large-scale patterns passive by currents --Small-scale patterns by movement in the BBL -Suspension feeding at low Re --Water doesn't pass through small trap easily --Sponges use a different method

trade winds

-Prevailing winds that blow northeast from 30 degrees north latitude to the equator and that blow southeast from 30 degrees south latitude to the equator

Reynolds Number (Re)

-Ratio of inertial forces to viscous forces associated with organisms in water --With a large Re= the inertial forces are dominant over viscous forces --For a small Re= just the opposite. -The longer the organism the higher the Reynolds number --organisms with high reynold number will have long, narrow bodies --organisms with low reynolds number will have short, fat bodies

Limits to exponential growth

-Resources are finite. -Finite resources mean a population can't grow exponentially indefinitely

Tides

-Rise and fall of the sea surface due to the SUN and MOON -Effects greatest on intertidal biota -Most shores experience a tide -Timing and amplitude vary greatly

Salinity

-SALT solution of the water -measured in parts per thousand (ppt or ‰)

Temperature and CO2 are strongly correlated

-correlation doesn't mean causatin Ways to establish cause and effect: -Remove predators to see if the prey responds. -Build climate models to predict how they might effect temp change -Use models and remove different factors

Earth's oceans

-cover 71% of earth's surface -CLIMATE is affected by oceans

How does Re number influence body design at high Re?

-Streamlines body design -Short, squat fish have high friction drag creating -a large wake that slows swimming speeds Streamlined fish (shark or tuna) minimize wake -The long fish can go fast and go long distances and reduces drag -The short fish goes short distances and lives in coral reefs and has more drag but they can also make sharp turns -why are fish slimy? --mucus reduces friction drag -Suspension feeding at high Re --water passes through a net or trap --Barnacles have a trap that help them capture food particles that move through the water, they put out a net to trap food

Nutrients in the ocean

-Surface waters of the open ocean are often nutrient starved -Deeper water will have less photosynthesis (light limited), higher decomposition (more free nutrients). -Influences vertical distribution of oxygen and contributes to bottom-water hypoxia

Subduction

-The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary.

Tolerance range

-Tolerance limits distribution (climate envelopes) and abundance -If there is a curve there is a range that an organism needs in order for it to keep its critical functions going

What controls Salinity?

-Variation GREATER in BAYS and SEAS than open ocean -varies MORE in SMALL bodies of water -Highly variable in ESTUARIES (where rivers and streams meet ocean) ex: where the MS River meets the Gulf of Mexico -salinity LOWER at equator bc of high rates of precipitation -sea-ice formation/melting causes variation ---salt is not in ice crystals ---when it melts, releases fresh water into the ocean ---fresh water is less dense than salty water water so it does not mix

Bernoulli's Principle

-Velocity doubles when the cross sectional area of a pipe is halved -Sponges benefit from Bernoulli's principle to increase water flow across their feeding cells

Which planet has the highest surface temperature?

-Venus because it has greenhouse gases trapping heat -Mercury is the closest to the sun but it does not have greenhouse gases trapping heat and has no atmosphere

tsunamis

-Wave caused by earthquakes, landslides or volcanic eruptions (often under water) At sea, fast-moving with low height and long wavelength

Temperature Depth Profile

-When stratified density (and temperature or salinity) varies with depth -dashed line= density -solid line= temperature *slide 13 on Ch 2 part 1

cladogram

-a branching diagram showing the cladistic relationship between a number of species

Pycnocline

-a change in density -caused by a halocline or thermocline or both

Population

-a group of individuals of a single species at a particular space and time

What were the effects of temperature on mussel SFG? (scope for growth)

-as temperature increases or food decreased beyond a certain point, SFG in terms of energy balance falls below zero -muscles do not thermoregulate (adjust body temp as temp changes)

competition exclusion principle

-based on interspecific competition -no two species (community ecology) cannot occupy the same niche -Superior competitor will drive the other to extinction

Other adaptations for homeothermy

-behavior -metabolic heat (ectothermy) -fur in pinnipeds (seals, sea lions, and otters) -blubber

tophat: Which of the following will have the highest Re when swimming through water (assuming all else is equal)? -Copepod -Blue crab -Tuna -Blue whale

-blue whale because it is longer in length

Continental Shelf

-broad, low sloping platform at the margins of continents -~ 8% of the total ocean but very productive -Varies with sea level - during glaciation, less of the shelf is underwater.

Drag

-caused by water moving past an object -FRICTION drag significant in LAMINAR flow (PULLS in direction of water flow) -PRESSURE drag more significant in turbulent conditions (higher velocity on the left side and will PUSH in the direction of water flow) -pushes you in the direction of flow

Stratification

-causes by difference in water density -causes water to stratify or layer - affects mixing and is variable through time

Benthic Zone of the ocean

-comprises the bottom, the sediment surface, and some sub-surface layers -describes the layers closer to the bottom of the ocean body -part of water touching a shelf of land

What determines tide pattern at the site?

-determined by interference of tides and landmasses (shape of basin)

Convergence zones

-major sinking zones near Antarctica and Greenland -At Greenland convergence, water sinks because high-salinity Gulf Stream water converges with cold water from Greenland. --Cold, salty water is very dense and sinks. --Sinking water is rich in oxygen from the surface -Gulf stream water has a high salinity due to evaporation and it is cooler than in the tropics. -If the Gulf stream were to stop, Europe would be cooler, perhaps move the earth to an ice age. -in convergence zones, salty water becomes colder and becomes more dense, it then sinks (this water is loaded with oxygen) -Convergence zones create "conveyor belt" with profound influence on global climate and deep sea

Rip current

-major source of mortality on beaches -current flowing on the beach, the velocity of the rip current can be fairly strong, can't swim against -people drown because they wear themselves out trying to swim against the rip

Positive Feedback

-makes things WORSE -warms the earth faster -amplify the effect How might this positive feedback further warming? -Warm water holds less dissolved CO2 leading to more warming -More evaporation = more water vapor -Thawing of permafrost releases more greenhouse gases making earth warmer -thawing of methane hydrates (most potent gas) -reduced albedo

When would you expect to find the greatest hypoxia?

-most hypoxia in the summer because there is more stratification

O2 minimum zone

-occurs in most oceans because respiration is high - occurs at ~500-1000 m in the mesopelagic -there is an oxygen minimum zone in deep deep ocean, a lot of oxygen at the surface and it goes down as it gets deeper

Diurnal tides

-one high tide and one low tide daily -in Gulf of Mexico

The Carbon Cycle

-plants can take up CO2 and can move through the food -some plants and animals die and CO2 is back in the atmosphere -some CO2 is buried underground for a long time -fumes released in the air from trains, cars, etc. also causes CO2 to be released

Logistic Growth

-population growth slows near Carrying capacity (K) -carrying capacity (K)= Maximum number of individuals an environment can support if resources are limited -*dN/dt = rN [K-N/K] -As N approaches 0 [K-N/K] becomes 1 or they are growing at an exponential rate -As the population (N) approaches K then growth stops as it approaches the carrying capacity -As the population approaches its max size, things start responding -still assumes a closed population

tophat: Death Rate > Birth Rate

-population is declining

Halocline

-rapid change of salinity with depth

Testing for competition

-remove a potential competitor and see if the other increases in population

Salinity and Density

-salty water is MORE DENSE and SINKS -In surface waters, EVAPORATION INCREASES salinity -RAINFALL and runoff from rivers DECREASES it -BOTTOM water and sediments are often HIGHER in salinity and LESS variable than surface waters

Neritic Zone of ocean

-shallow part of the sea near a coast

How have sponges adapted to better suspension feed in a low Re environment?

-sponges increase water flow across their feeding cells -many thousands of collar cells per sponge and many pores where water enters (water leaves from the osculum)

specific heat capacity

-the energy required to raise the temperature of one gram of a substance by one degree Celsius

climate envelope modeling

-the range of temp in which a species can tolerate -For any given species may have a temp too cold or too hot so you can look in the range of the habitat in which the species lives so you can look at this to see what range is suitable for the species

What is ecology?

-the scientific study of the biotic and abiotic factors that determine the distribution and abundance of organisms

Coriolis Effect

-there is a point on the equator that travels faster than at the poles -coriolis effect is caused by this rotational velocity difference -Circumference of the earth is greater at the equator - A body traveling toward the equator with the slower rotational speed of higher latitudes tends to fall behind or veer to the west relative to the more rapidly rotating earth below it at lower latitudes -Similarly, a body traveling toward either pole veers eastward because it retains the greater eastward rotational speed of the lower latitudes as it passes over the more slowly rotating earth closer to the pole -the rate of the earth spinning depends on where you are -slide 5 on chapter 2 part 2

Homeothermy

-thermoregulation that maintains a stable internal body temperature regardless of external influence

Flooding tide

-tide coming up onto a shoreline

Ebb tide

-tide receding away from shoreline

How are Gulf of Mexico (LA tides) special?

-tides are Microtidal (0.3 m amplitude) ---2-4 m on east coast ---LA tides not lunar-dominated -Wind- and precipitation-dominated with highly variable tidal flooding ---Winds may cause water to pile up or push it out of areas -Cold fronts pass every 3-8 days in winter, winds push water out of coastal marshes ---average water level drops by 0.3 m ---low tide can last for several days and desiccation may be stressful -In spring, rainfall increases water level and marshes may be flooded continuously for several days, also stressful ---spring flooding can rise the tide up

Lunar month

-time it takes for moon to orbit the earth -27.5 days -time between spring tides or two neap tides) ~2 weeks

Thermocline

-transition in temperature

Causes of prehistoric climate change- Greenhouse gases

-traps outgoing radiation -First hypothesized in 1859 -Greenhouse gases include CH4, CO, H2O, CO2, O3, N20 -H2O most abundant (water vapor)* -CH4 most potent* -the atmosphere is only about 0.04% CO2 but it contributes the most to climate change bc it is in the atmosphere the longest bc of human activities* -the earth would be a lot colder and not hospitable if not for greenhouse gases

CTD Probes

-use electrolyte properties to measure conductivity, temperature and depth from ship -conductivity can be used to measure salinity

Causes of climate change a million years ago

-volcano eruptions (releases aersols cooling in short term or long term by emitting lots of greenhouse gases) -also an increase in plant life (by cooling it by reducing the amount of atmospheric CO2) -aerosol gasses cool and greenhouse gases warm -variation in solar output -Milankovitch cycles -Earth's orbit changing

Impact of all this freshwater: Initially, is the clam's blood hypertonic, hypotonic, or isotonic to the lake water? Where will the water flow?

-water flows into the clam

Keystone species concept

-where a species can suppress or control an area so that the dominant species won't take over

Estuaries

-where freshwater meets the ocean -Loaded with nutrients ---Highly productive (a lot of life here) -Salinity fluctuates greatly ---High osmotic stress for many species ---Not very diverse (bc a lot of organisms cannot cope with the high osmotic stress) ---Species that can tolerate environment can be in high densities -different degrees of estuaries determine the stratification

tophat: Imagine placing a thermometer in the body cavity of the worm and the urchin. Then place them in a cold environment. Which one would you expect to cool off first?

-worm (it has a higher SA/V ratio)

Osmoregulation in marine fish vs. freshwater fish

1.) Freshwater fish: -Water wants to flow inside and they pee a lot to get it out -actively uptake ions to offset what they lose -(hyperosmoregulator) 2.) Salt water fish: -water from the inside wants to flow outside of the fish so they drink sea water -actively excrete ions out of their body -(hypoosmoregulator)

What are the factors that limit the abundance and distribution of a species?

1.) Abiotic tolerance -no white sharks in rivers 2.) Predation/parasitism -Top-down control of mussels 3.) Food resources and competition -nutrient limitation in an open ocean --open ocean is nutrient poor 4.) Dispersal -Dispersal abilities vary greatly depending on method --Large migrations and planktonic larvae have higher dispersal abilities

Acclimation vs. Adaptation

1.) Acclimation: -reversible changes in tolerance or physiological condition over weeks-months -Most organisms acclimate to seasons -Lower lethal limit may be 10 degrees C in the summer but much lower in the winter -Stepwise acclimation is changed over a certain time scale 2.) Adaptation: -change by natural selection -occurs over generational time -ex: Blue crabs in Canada have a different tolerance to temperature than crabs do in GOM

How is tolerance measured?

1.) Bioassays measure tolerance: -Lethal endpoint: LC50 = concentration that kills 50% of a population -LC = lethal concentration - LD = lethal dose -LT = lethal temperature 2.) Reproduction, feeding rates and energy budgets are often used to measure "stress"/sub-lethal effects

evidence of global warming

1.) Current warming not uniform -temperatures are warming but it is not uniform -the arctic is where you are seeing the most warming 2.) retreating glaciers -Decrease in mass balance of glaciers overall and see that there are more receding 3.) Reduced spring snow cover in Northern hemisphere 4.) Rising sea levels -as the oceans warm, they expand (thermal expansion) -and from melting land ice -thus rises global temperatures 5.) sea levels more acidic -Oceans have change in pH -CO2 released making it more acidic -Rising sea levels consistent with a warming climate 5.) changes in seasonal activity -good biological evidence that temperatures are warm -Things that species would do in spring, they are starting to do earlier in the year

Laminar flow vs. turbulent flow

1.) Laminar flow: -has a low velocity input (steady flow) 2.) Turbulent flow: -has a high velocity input (swirling flow with chaotic movement of water)

osmoregulators vs osmoconformers

1.) Osmoregulators: -maintain a constant internal environment for water or ions -maintain homeostasis but require a lot of energy -two types: --Hyperosmoregulators= Maintain higher concentration of salts in their surrounding external environment --Hypoosmoregulators do the opposite; Maintain a lower concentration of salts -ex: water wants to flow in the oyster and dilute the salinity of the blood of the oyster -fish can control this but oysters can't because they have a broad tolerance of blood salinity 2.) Osmoconformers: -vary as the external conditions vary (oysters) -Internal osmotic properties not adjusted physiologically -passive diffusion of ions and water eventually bring the body into equilibrium -Feeding may be disrupted and the animal stressed

If competition exclusion principle is common, then why do so many species coexist? (niche partitioning and character divergence)

1.) niche partitioning: -one species may have their niche at the top of a tree and the other at the bottom 2.) character divergence: -where niche partitioning can be beneficial and favored by natural selection -Selection may favor traits that allow for better partitioning -Over time physical traits may diverge

Steps of the Scientific Method

1.) observe 2.) ask a question 3.) hypothesize 4.) experiment 5.) collect data 6.) analyze 7.) draw conclusions 8.) publish

Monthly tidal cycle and how affected by sun and moon patterns

1.)At FULL MOONS: -the sun, moon, and earth are in a straight line: -Sun increases pull and highs are higher and lows lower than normal -leads to the highest tidal amplitude called a SPRING TIDE -happens twice a month 2.) At QUARTER MOONS: - the sun and moon are at quarter angles from each other high tides lower than normal and low tides not as low -tides are at its lowest amplitude -called a NEAP TIDE -lunar month= takes about 27.5 days to go through this cycle (moon going all the way around the earth)

If competition exclusion principle is common, then why do so many species coexist? (disturbance)

3.) disturbance: -low disturbance= large boulder bc they are heavy and therefore turn over less frequent from waves -high disturbance= small boulders that are light in weight and constantly turning over from waves -intermediate disturbance= have the most diversity -INTERMEDIATE DISTURBANCE HYPOTHESIS= local species diversity is maximized when ecological disturbance is neither too rare nor too frequent

ecosystem

A biological community of interacting organisms and their physical and chemical environment.

Pseudoscience

A fake or false science that makes claims based on little or no scientific evidence.

turbidity

A measure of how clear water is due to suspended particles

Community

All the different populations that live together in an area

Impact of all this freshwater: Is the blood hypertonic, hypotonic, or isotonic to the intracellular fluids? Where will the water flow?

Blood lower in salinity and water flows into the cells and the salinity of the clam will match the salinity around it

Monthly tidal cycle summary

Day 1: FULL MOON= SPRING TIDE (sun, earth and moon aligned) Day 8: 1ST QUARTER= NEAP TIDE (sun and moon quarter angles from each other) Day 15: FULL MOON= SPRING TIDE (sun, earth, and moon aligned) Day 22: 3RD QUARTER= NEAP TIDE (sun and moon at quarter angles from each other) Day 29: FULL MOON= SPRING TIDE (sun, earth, and moon aligned) ***every seven days, moon changes, alignment changes, and tide changes

Indirect effects of flow

Flow may alter: -sediment type --prevents sedimentaion with strong currents -bacterial and algal abundance --depend on where water takes them -resuspension/turbidity --how murky the water is --flow of water determines how clear it is -oxygen content

Exponential growth model

If you assume a closed population: -*r = birth rate - death rate -emigration and immigration is removed from this model -dN/dt = rN --r= intrinsic growth rate --dN/dt=growth per unit time Graph: -has an exponential growth curve -population growing exponetially

Seasonal Stratification cont'd.

In shallow temperate bays, continental shelf or temperate open ocean: --stratification starts in spring and ends in fall with increased wind and lower temperatures --in the WINTER, water columns MIX --in the SUMMER, water column thoroughly STRATIFY; --Bays in the TROPICS can be stratified year round bc temp is usually constantly warm year round --start to mix again in the late fall

When did this CO2 increase start?

Industrial Revolution -CO2 started accumulating from the Industrial Revolution that began in the 1760's Deforestation - Reduced Carbon Removed from Atmosphere Burning Fossil Fuels -combustion reaction -Organic molecules + O2 --> CO2, H2O, and heat -anthropogenic= man driven -Transportation and electricity are significant contributors

Practical relevance of oceans to people

Industries based on marine organisms -Fisheries -Tourism -Pharmaceuticals Ecological services provided -Hurricane buffers -Water filtration -Carbon sinks

Intraspecific vs. Interspecific competition

Intraspecific -Within species -Increases with density Interspecific -Between species (community ecology) -Can also increase with density

Impact of all this freshwater: (impact on salinity)?

It is reduced

Effects of Stratification

May influence distribution of plankton and chemical factors -Would expect phytoplankton above the cline bc greater nutrients above -In the winter, water column mixes so not a lot of sunlight and not a lot of phytoplankton

Niche concept

Niche: -role of an organism within the community or relationship of a species to all aspects of the environment (biotic & abiotic) -Based on activity (tolerance) range for an environmental variable - activity range (tolerance range generally refers to abiotic factors only) - Quantify niche by categorizing activity range for all abiotic dimensions -activity range for a dimension = the range over which the organisms has positive fitness

What is causing current climate change?

Reasons these things are not: 1.) Milankovich cycles don't appear to explain current warming: -Time scale of Milankovich cycles too large to explain current warming -takes 100,00 years to go through the orbit cycle and 26,000 years to go through the wobbling cycle, and 41,000 years to go through the orbit cycle 2.) Solar output doesn't appear to explain current warming: -more sunspots means more heat put out by the sun, every 11 years there is a peak -Temps increasing in troposphere but decreasing in the stratosphere -stratosphere is cooling -If the sun were putting out more heat, you might expect all layers to be increasing, which the stratosphere is not 3.) Aerosols don't appear to explain current warming: -Particles that reflect solar radiation and have a cooling effect BUT.. -Greenhouse gases are still plausible cause of current warming

How does stratification develop?

Stratification often seasonal (TEMP) -SPRING= sun warms surface water and the deeper water isn't getting as much heat so we get a layer -WINTER= the surface waters are cooling off and may become the same temperature as the deeper water, so no stratification SALINITY -a halocline is generated when fresh water is released on surface by: 1.) melting sea ice 2.) large river input

Common use of word Theory vs. Scientific Theory

Theory -a hunch or speculation Scientific Theory -an explanation of an aspect of the natural world that can be repeatedly tested and verified in accordance with the scientific method

Scope for Growth

Used to determine if a population can persist under certain environmental conditions -*S (scope for growth) = Eg + Er - (Em + Eu) --Eg=allocated to growth --Er=reproduction --Er=metabolism --Eu=excretion -If SFG > 0, growth and reproduction possible -If SFG < 0, stored reserves used/ they use energy stores

tophat: As a northern hemisphere Hadley Cell returns to earth, it will be deflected:

West

The ___ has a greater effect on tides because it is ______.

moon; closer

Impact of all this freshwater: clams in the estuaries are?

osmoconformers

control group

the group that DOES NOT receive the experimental treatment.