Exam 1 Marine Ecology

Community stasis can be driven from top down, how?

-by the influence of predation & competition

-population of the organisms lower trophic levels are controlled by the organisms at the top

To understand where reefs are headed in the future we must...

-do a better job studying the combined influence of multiple stressors

-identify tipping points where communities undergo rapid change to an alternative stable state

What 3 complementary approaches can we use to manage & govern coral reefs so they can survive & remain functional?

-A greater focus on reducing important drivers of change could help to avoid crossing thresholds that lead to environmental degradation

-Opportunities to manipulate ecological thresholds so that stronger drivers are required to induce a regime shift or to cause unacceptable levels of degradation

-Feedbacks could be actively altered to flatten the slope of the response curve

Eukarya

protists, plants, fungi, & animals

polyphyletic clade

includes species that lack a common ancestor (lobsters, algae, corals)

paraphyletic clade

a taxonomic group that excludes some of the descendants from a specific common ancestor (fishes, crustaceans)

Ctenophora

comb jellies

Echinodermata

sea urchins & sea stars

Annelida

Polychaeta

Biomineralization

ability to sequester elements & then "cement" them together into bio-minerals

Functional traits

any characteristic of an organism that influences its fitness by affecting growth, reproduction, or survival

Ecosystem services of plankton & nekton

-production of natural gas & oil

-humans consuming fish for protein

Benthic Fauna

organisms living on the bottom substrate

microbes

benthic fauna; sulfur oxidizing symbionts of clams, critical in detoxifying sulfur

Meiofauna

live between grains of sand (nematodes)

macrophytes

aquatic plants; primary producers in marshes (spartina cordgrass)

microepiphytes

attached to other organisms (hydroids, calcareous algae)

osmotroph

an organism that gets energy by taking up small dissolved molecules from the surroundings; absorbing organic compounds

Coroilis effect

the deflection of air or water flow, relative to the solid earth beneath, as a result of the earth's rotation

Currents move ______________ in the northern hemisphere, _______________ in the southern hemisphere.

clockwise; counterclockwise

Ekman transport

movement of surface waters at a right angle to the direction of the wind due to the Coriolis effect

T/F: Thermohaline circulation recycles nutrients in the ocean.

true; carbon gets taken down to the bottom of the ocean where it will decompose

continental shelf

the area of seabed around a large landmass where the sea is relatively shallow compared with the open ocean

continental slope

slow between the outer edge of the continental shelf & deep ocean

Biodiversity gradients are highest at _____ latitudes.

low

Biodiversity gradients are highest in the _______ Sea.

Coral

Biodiversity gradients are highest at the _______.

surface

Larger areas have _____ species.

more

Ecological drift (genetic drift)

ecological process of random fluctuation in species abundance that are unrelated to competition, predation, physical tolerance, or other deterministic processes (so random loss of species due to chance)

allopatric speciation

origin of new species between populations that are separated geographically

parapatric speciation

origin of new species by divergence of populations along an ecological transition while the populations remain physically and demographically connected; will have some hybridization; majority of marine species fall into this category; a lot of opportunity for gene exchange

sympatric speciation

origin of new species in the absence of physical barriers to interbreeding by divergence of subpopulations that differ in habitat or other resource use or mating behavior

What is dispersal ability in marine organisms based on?

life history traits, especially the presence of pelagic larvae

Generally, species with longer pelagic larval duration have _______ geographic ranges, _______ rates of speciation, and ______ levels of endemism.

greater; lower; lower

If your geographic range is large then the range of speciation is ______.

low

Organisms with a wide habitat breadth have a _______ speciation rate.

lower

What do larvae use to keep them from gettin swept away from the currents?

vertical migration

theory of island biogeography

suggests that the equilibrium number of species on an island is that number that balances immigration from a source with extinction due to habitat limitation

Describe the distance-immigration curve?

the distance-immigration curve is strongly influenced by pelagic larval duration

T/F: Extinction in the sea remains scarce.

true

What were the assumptions made by the MacArthur & Wilson Model?

-Rate of colonization (dispersal) decreases with distance from mainland

-rate of extinction increases as the richness of our island increases

-rate of extinction decreases with island size

-equilibrium species richness is where colonization & extinction are equal

greenhouse effect

Carbon dioxide and other greenhouse gases trap solar-derived heat in the atmosphere near the earth's surface

What are some natural changes that are changing our atmosphere?

-rotational wobble

-volcanic activity

Carbonate ions are essential for...

-shell formation in mollusks

-skeleton formation in corals

Volcanic vents

-have elevated CO2 & lowered pH

-communities had higher density of seagrasses, lower seagrass epiphytes, fewer corals & sea urchins, and damaged shells for snails & limpets

"The Predicament of Mankind" study

-published "The limits of growth"

-developed first system dynamic model that linked global economy w/ the biophysical environment

GDP (measure of economic metabolism) is ________ related to energy consumption.

positively

What is energy consumption positively related to?

-calories that a population takes in

-Nobel prize per capita

-waste increasing

What is energy consumption negatively related to?

-infant mortality

-poverty

Anthropocene

the modern geological era during which humans have dramatically affected the environment

The Voyage of the HMS Beagle

5 year voyage around the world on which Darwin explored and collected fossils

Pisaster Starfish

example of a keystone species

keystone species

A species that influences the survival of many other species in an ecosystem

Niche

An organism's particular role in an ecosystem, or how it makes its living.

Community stasis can driven from bottom up, how?

-by the availability of resources such as space, light, salinity, nutrients

-lower trophic level affects the community structure of higher trophic levels by means of resource restriction

What else can community stasis be driven by?

by patterns of disturbance & recruitment

intermediate disturbance hypothesis

predicts that community diversity is the highest when disturbance is intermediate

What are higher levels of CO2 in the atmosphere directly related to?

-higher sea surface temperatures

-higher bicarbonate concentrations

-lower pH (acidification)

To better manage our reefs, we must....

-highlight the loss of ecosystem goods & services

-understand the direct & indirect links between reef health & human well-being

How will the loss of biological diversity alter the functioning of ecosystems & their ability to provide society with the goods and services needed to prosper?

biodiversity loss reduces the efficiency by which ecological communities capture essential resources, produce biomass, decompose & recycle nutrients

ecosystem functions (BEF)

biomass production (creating energy), nutrient cycling, & decomposition

ecosystem services (BES)

provisioning services (wood, foot, etc.) & regulating services (heat balance, storm production, etc.)

What are the 3 domains of life?

Bacteria, Archaea, Eukarya

Bacteria

-prokaryotes

-single cell w/ no nucleus

-rarely have organelles

-have glycerol-ester lipids in membrane

-nitrogen fixation, photosynthesis, fermentation, & autotrophy

-ex: cyanobacteria (blue green algae)

Archaea

-prokaryotes

-single cell w/ no nucleus

-lack organelles

-use glycerol-ether lipids

-nitrogen fixation, sulfur oxidizers, & methanogenesis

-halophiles

-hyperthermophiles

monophyletic clade

a taxonomic group that includes ALL of the taxa/species descended from a specific common ancestor (mollusks, sponges)

Protists (paraphyletic)

-foraminifera & radiolarians

-diatoms, dinoflagellates, & brown alga

-red & green alga

-slime molds

Plants (monophyletic)

-sea grass

-mangroves

fungi (monophyletic)

-yeast

-saprobes

-parasites

-symbionts

Animals (monophyletic metazoans)

-Ctenophora

-Porifera

-Cnidaria

-Echinodermata

-Chordata

-Annelida

-Mollusca

-Arthropoda

Porifera

sponges

Cnidaria

anemones & jellyfish

Chordata

sea squirts & vertebrates

Mollusca

snails, clams, squids, octopuses, mollusks

Arthropoda

crustaceans

Plankton

microscopic organisms that live in aquatic environments incapable of moving against currents; includes both phytoplankton and zooplankton

Nekton

organisms that swim strongly enough to move against the current

Ecosystem function of planktons & nektons

-photosynthesis

-carbon nutrient recycling

Plankton is classified how?

by size;

1) picoplankton (0.2-2.0um)

2) nanoplankton (2.0-20um)

3) microplankton (20-200um)4) mesoplankton (0.2-20mm)

5) macroplankton (>2.0cm)

6) Nekton - free swimming

7) megafauna

Macroinfauna

have special adaptions that allow them to get water deep in their burrows (clams, worms, & ghost shrimp)

Macrofauna

animals visible to the naked eye (mollusks, echinoderms & crustaceans)

Why does functional traits scale with body size?

-measuring size of an organism allows a rough estimate of its metabolic rates, feeding rate, swimming speed, & sensory range

-body size strongly affects biological rates and modes of life

Chemautotrophs

Obtain energy directly from chemical reactions; oxidizing inorganic compounds

Phototrophs

obtain energy from light; sunlight driven carbohydrate synthesis

Heterotroph

An organism that cannot make its own food; viruses, deposit feeders, suspension feeders, grazers, parasites, & predators

Sheldon's Rule

state, that the abundance of an organism is closely linked to its body size; so the smaller the organism, the more of them you find in the ocean

What are all the predictions of Sheldon's Rule

1) numbers of each size class will decrease at a slope of -1.0

2) biomass for each size class will be approximately the same (1 GT)

How many oceans does the Earth have?

one ocean divided into different basins with distinct circulation patterns

What are ocean currents driven by?

-Coriolis effect

-differential heating of the equator driving predictable patterns of wind

-Ekman Spiral

-geostrophic flow

-position of the continents

Geostrophic flow

large scale circular flow around an ocean basin (gyre), generated by the balance between Coriolis-induced pressure inward & gravity-forced pressure outward

thermohaline circulation

global movement of water through the deep ocean, beginning with the sinking of cold saline waters during polar winters, & its slow flow through the deep ocean basins until upwelling again

Thermohaline circulation is driven by:

differences among water masses in temperature & salinity that affect density

convergent fonts

when two water masses flow together; causes downwelling

How many realms of marine biodiversity are there? What do they depend on & what do they reflect?

12-30 realms; depending on the criteria for grouping species pool similarity, habitat specialization, & importance of endemism; reflect the first & second order circulation patterns among ocean basins

Endemism

degree of taxonomic uniqueness of an area, usually expressed as the proportion of taxa that are unique to the area & considered to have origenated here

What are the gradients of species diversity?

-latitude

-longitude

-depth

Dispersal (gene flow)

ecological process of movement of organisms, usually referring to permanent movement away from a place of birth; lowers endemism & impedes speciation

Ecological selection (natural selection)

Ecological process for the deterministic interactions among organisms and their environment that influence which species are present in a community

Speciation rates ______ with geographic range, temperature, body mass, & habitat breadth.

decreases

Warmer temperature leads to ______ speciation rates.

lower