Marine Ecosystems 1

ocean’s earliest navigators

pacific islanders

considered to be the first marine biologist

aristotle - described 117 fish species

james cook

first to make scientific observations, went on 3 voyages, first to use a chronometer, killed by native hawaiians (1779)

charles darwin and sms beagle

proposed theory of evolution, theory of how coral atolls form

edward forbes

malacologist (clams and snails), found animals density and diversity decreases with depth

challenger deep

deepest known point of seabed (mariana trench)

d/v glomar challenger

continental drift and seafloor spreading evidence, age of seafloor determined

d/v/ joides resolution

drills into ocean core, shamar was on it i think

d/v chikyu

drill to mantle/seismogenic zone

sonar (sound navigation and ranging)

developed for growing threat of submarine warfare

SCUBA (self-contained underwater breathing apparatus)

developed for automobiles to run on compressed natural gas

alfred wegener

first to identify pangea and theory of continental drift

clues to plate tectonics

fit of continents separated by ocean

matching structures across present oceans

distribution of fossil organisms with limited geographic ranges

volcano distribution

theory of the geodynamo

mechanism by which a celestial body generates a magnetic field

magnetic poles

point of compass needle, slightly offset of geographic poles

earth rotation

geographic north and south poles

paleomagnetism

magnetic polarity preserved in igneous rock, determines when rocks formed

magnetic reversals

176 reversals in the past 76 million yrs, unpredictable

marie tharp

discovery of the mid atlantic ridge

3 types of plate boundaries

divergent, convergent, transform

divergent boundaries

within continental crust: continental rifting, formation of new ocean

within oceanic crust: seafloor spreading

ocean-ocean divergent land forms

mid ocean ridges, rift valleys, seafloor spreading, ocean basins, hydrothermal vents

continental-continental divergent land forms

rift valleys, new oceans

driving forces for divergent motion

mantle plumes

ocean crust density

as it gets older, contracts and gets denser

ocean-ocean convergent boundary

ocean trench (subduction), accretionary wedge, volcanic island arc

accretionary wedge

pile of deformed ocean sediment scraped off subducting plate

volcanic island arc

partial melting of subducting slab

ocean-continental convergent plate boundary

ocean crust denser, always subducts under continental

island arcs

curvature of the Earth, the subduction zone, and the chain of islands, is arc-shaped

tall oceanic volcanos

grow tall enough, become islands

continental-continental convergent

mountains

3 growth stages of an ocean

embryonic: uplift

juvenile: divergence, narrow seas

mature: divergence, ocean basin w continental margins

growth of an ocean

3 destruction phases of an ocean

declining: convergence (subduction)

terminal: convergence (collision) and uplift

suturing: convergence and uplift

destruction of an ocean

ocean life cycle

made at mid ocean ridges, consumed at subduction zones

hotspots

isolated plumes in the mantle, melted lithosphere rises through crust, forms a seafloor volcano, stationary so as plate moves forms island arc chain

atoll

ring shaped coral reef system w central lagoon rising from deep water

seamount

mountain rising from ocean seafloor, does not reach surface (underwater mountain)

guyot

flat topped seamount

formation of atolls

volcano acquires fringing coral reef

volcano becomes inactive begins to erode and subside (sink)

reef continues to grow upwards at a rate faster than
rate of volcano sinking

only growing fringing reef remains with deep central
lagoon

oldest to youngest

guyot, seamount, island, hotspot

properties of water

high heat capacity, high heat of evaporation, high dissolving power, high transparency (absorbs infrared, ultraviolet), high latent heat of melting

thermocline

transitional layer between warmer mixed water and cooler deep water

salinity

grams of dissolved salt per 1000 g seawater

salinity controlled by

evaporation, sea ice formation, precipitation, river runoff

seawater important elements

chlorine, sodium, magnesium, sulfur, calcium, potassium, bromine, carbon

principle of constant element ratios

ratios are constant even with varying salinity

coriolis effect

movement of fluids in relation to earth beneath results in deflections.

right in NHem, left in SHem

upwelling

coastal winds + coriolis effect (

thermohaline circulation controlled by

location of formation of water, density, coriolis (to a degree)

global ocean conveyor belt

origin: high lat surface waters

high salinity + low temp = high density

circulation types and effects

coriolis: upwelling, deflection of currents

surface: gyres, eastern boundary currents

thermohaline: water masses (density determined)

fetch

amount of open water a wind blows over

larger fetch = bigger waves

waves

Highest point of a wave is the crest, the lowest point is the trough.
Distance between two crests is the wavelength

Time is takes for a wave to pass by a set point is the wave period.

tides

waters on the side of the earth that are closer to the moon cause a high tide

waters on the side of the earth further away from the moon cause a low tide

tides are usually higher at night and lower during the daytime

tidal range = diff between high and low tides

diurnal tide cycle

one high tide one low tide every lunar day

semidiurnal tide cycle

two high tides and two low tides per lunar day, approx equal in size

mixed semidiurnal tide cycle

two high tides and two low tides per lunar day, diff in size

four organic molecules

carbohydrates, proteins, lipids, nucleic acid

made of carbon, hydrogen, oxygen

carbohydrates examples

cellulose, chitin

proteins examples

enzymes, hormones, structural

lipids uses

insulating layer, buoyancy, energy storage

levels of organization

Population: group of organisms of the same species
living in the same habitat
Community: all of the species that live in a particular habitat
Ecosystem: a combination of the community and the physical environment

diffusion vs osmosis

diffusion = mvmt of solutes

osmosis = mvmt of water

osmoconformers

internal concentration varies as the salinity in the water around them changes

tolerate narrow range of salinities

osmoregulators

control their internal concentrations of solutes and water

tolerate wider range of salinities

ectotherms

generate body heat metabolically, heat is
rapidly lost so organisms cannot maintain a constant internal body temp; matches that of the surrounding
environment

endotherms

retain most metabolic heat, and body temp stays higher that that of the surrounding environment

poikilotherms

body temp varies with the temp of the surrounding environment

homeotherms

regulates body temp

asexual reproduction examples

fission: two of equal size

budding: small buds form and break off

vegetative reproduction: underground stem sent sideways, new plants sprout from it

colonial reproduction

genetically identical, compose a module if connected

natural vs sexual selection

natural: increase fitness

sexual: increase mating success

two types of sexuality

gonochoristic: separate sexes

hermaphroditism: can have male or female function (simultaneous or sequential)

cyanobacteria

photosynthetic bacteria most
important in the marine enviro

stromatolites

massive calcareous mounds formed by cyanobacteria

marine bacteria role

break down dead organic matter forming detritus

chemosynthetic

energy from chemical compounds

heterotrophs

energy from organic matter by means of respiration

marine diatoms

photosynthetic, yellow brown in color, silica shell, reproduce by cellular division

marine dinoflagellates

shape enforced by cellulose, two flagella, some are bioluminescent

zooxanthellae

dinoflagellates have symbiotic relationship with
many organisms

foraminiferans

exclusively marine, non photosynthetic (are heterotrophs), shells of calcium carbonate, pseudopods

radiolarians

planktonic, shell of silica, pseudopods

silicoflagellates

star shaped silica skeleton, two flagella of varying lengths

coccolithophores

exclusively marine, photosynthetic, shells of calcium carbonate, annual blooming events

ciliates

hair like cilia, most live as solitary cells

biological classifications

Dear – Domain
King – Kingdom
Philip – Phylum
Come – Class
Over – Order
For – Family
Great – Genus
Spaghetti – Species

species

individuals that have many characteristics in
common and the ability to breed successfully with each other.

3 cell layers

ectoderm, mesoderm, endoderm

coelem

cavity that develops in embryo within mesoderm

deuterostome

symmetrical/radial cleavage

protostome

asymmetric/spiral cleavage

sponges

all are sessile (attached), filter feeders through pores, asymmetrical body plan, asexual budding and sexual reproduction

cnidarians

radial symmetry, free swimming or attached forms, nerve net

arthropods

phylum with largest number of species

chitin exoskeleton, must be shed to grow

crustaceans: dominant marine arthropods, open circulatory system, internal fertilization

planktonic organisms

microscopic organisms that cannot propel themselves/are weak swimmers

drifters or floaters that are carried along by tides or currents

copepods

eat phytoplankton by filter feeding

are primary consumers