Marine Science Vocabulary Terms

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

A

Abiotic - non-living (physical or chemical component of the environment

Aboral surface - the area of an animal located by the anus

Abyssal gigantism - phenomena where animals attain a large size no found anywhere but in the deep sea

Abyssal Plain - the nearly flat region of the sea floor

Abyssopelagic - an area of the pelagic environment at an approximate depth of 4,000 m - 6,000 m. This area is aphotic

Acipenseridae - taxonomic family which contains the sturgeons

Acoelomate – animals lacking a true internal body cavity The region between the body wall and the gut is solid (occupied by mesoderm)

Acontia - structures used as defense in many species of anthozoans. Usually loaded with nematocysts

Acropomatidae - taxonomic family which contains the wreckfishes

Actinopterygii - subclass of fishes which contains the ray-finned fishes

Adductor muscle - found in bivalves and is responsible for closing the valves

Adipose fin - fatty fin which lacks bony rayed supports, found in the salmonids and synodontids

Aerobic respiration - respiration in the presence of oxygen

Ahermatypic corals - corals which are non-reef building

Ambergris - collected indigestible found in the digestive tract of sperm whales, often used in fine perfumes

Ammocoete - larval stage of the sea lamprey which lives a secretive life filter feeding buried in the sediment

Amoebozoa - phylum of protozoans (not covered in class)

Ampullae of Lorenzini - gel filled pit in the rostrum of cartilaginous fishes used to sense weak electrical currents

Anadromous - fishes which spend their adult life in water and migrate freshwater to spawn

Anaerobic respiration - respiration in the absence of oxygen

Anguilliformes - taxonomic order which contains 15 different families of true eels

Animalia - multicellular, heterotrophs (kingdom)

Antennariidae - taxonomic family which contains the frogfishes

Anthozoa - class in the phylum Cnidaria which contains the corals and sea anemones

Apex predators - top predators

Aphotic - complete and total darkness

Archeocytes - phagocytic cells found in sponges which aid in digestion, also give rise to sperm and eggs

Asexual reproduction – replication of chromosomes and the splitting of the parent into two or more parts. Asexual reproduction occurs in some invertebrates and is the only method for a few

Asymmetrical – have no ordered symmetry pattern to the organisms' gross morphology

Atherinidae - taxonomic family which contains the Silversides

Aulostomidae - taxonomic family which contains the Trumpetfishes

Authigenic sediment - particles that are precipitated by chemical or biochemical reactions in seawater near the sea floor. (i.e. Manganese and phosphate nodules)

Autotroph - an organism that manufactures its own organic matter by using energy from the sun or other sources

Azoic theory - A theory first proposed by Edward Forbes which stated that no life existed on the sea bed below 300 fathoms (1,800 ft). This theory was later proved incorrect

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B

Back-island flats - barrier island features which are sand deposits shaped like pancakes or lobes. These areas are usually created by washover or overwash

Baleen - material found in the upper jaw of baleen whales used for straining food during the feeding

Balistidae - taxonomic family in the order Tetraodontiformes which contains the Filefish & Triggerfish

Barrier islands - large deposits of sand that are separated from the mainland by bays, estuaries, or lagoons These bodies of water are regularly flushed through tidal inlets

Bathypelagic - area of the pelagic environment at an approximate depth of 1,000 m - 4,000 m. This area is aphotic

Batrachoididae - taxonomic family which contains the toadfishes

Belonidae - taxonomic family which contains the Needlefishes

Benthic (benthos) - sea bottom

Berm - a prominent wave deposited feature of most beaches; accumulation of sand having a flat top and steep seaward slope.

Beroida - order of ctenophores

Bilateral symmetry – right and left sides that are mirror images of each other

Binary fission – a type of asexual reproduction that results in two individuals

Binomial nomenclature - a system of naming species using two names, the first of which refers to the genus

Biogenic sediment - derived from the hard parts of organisms such as shells and skeletal debris (i.e. - calcium carbonate and silicon dioxide

Bioluminescence - light which is produced by living organisms

Biotic - a living component of the environment (i.e. predation, competition)

Bivalvia – class of molluscs which contains clams, mussels, oysters, and shipworms

Blenniidae - taxonomic family which contains the Blennies

Bothidae - taxonomic family in the order Pleuronectiformes which contains the Left-eye flounders

Bottomset beds - sediments of the prodelta which are composed of several layers of silts and clays

Brackish - body of water where fresh and salt water mix, creating an area of varying salinity

Breakwaters - man made structures built as barriers in front of harbors or shorelines. Usually built offshore parallel to the beach or harbor mouth and absorb the pounding of the sea

Budding – portion of the parent breaks off and differentiates to form a new complete individual (a type of asexual reproduction)

Byssal threads - filamentous structures which mussels secrete and use for attachment

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C

Calcarea - class of sponges. Spicules are made strictly of calcium carbonate

Cannibal viviparity - reproductive method favored by predatory sharks. Young in each oviduct consume unfertilized eggs or other siblings during development

Capillary waves - smallest waves, have a period > 1/10 of a second Created on a flat day by a brief gust of wind

Carangidae - taxonomic family which contains the Jacks

Carapidae - taxonomic family which contains the pearlfishes

Carnivora - taxonomic order which contains the Polar bears, sea otters, seals, sea lions, and walruses

Carnivores - eat meat

Carrying capacity - the largest population or community size that can be sustained by an ecosystem is called its

Catadromous - reproductive strategy where fish live most of the lifecycle in freshwater and migrate to saltwater to spawn. I.e.: American eel

Celerity - term used for the velocity of a wave form

Cephalic lobe (beard) - The anterior portion of pogonophorans that contains thousands of ciliated tentacles and a gland that secretes a chitinous tube

2. Functional limbs on the head used for directing plankton

Cephalochordata - subphylum which contains the lancelets or amphioxus

Cephalofoil - term used when referring to the head of hammerheads

Cephalspidomorphi - taxonomic class which contains the lampreys

Cephalopoda – class of molluscs which contains squid, octopus, cuttlefish, and chambered nautilus

Cerata - respiratory projections on the dorsal surface of sea slugs

Cestoda - class of parasitic tapeworms in the phylum platyhelminthes

Cetacea - taxonomic order which contains Whales, dolphins, and porpoises

Chaetodontidae - taxonomic family which contains the Butterflyfishes

Chemoautotrophs - organisms which use chemicals in the synthesis of nutrients

Chinese liver fluke - parasite which is found in the bile duct. Originates from eating raw fish

Chitin - complex carbohydrate that is the main component of the skeleton of many invertebrates

Chondrichthyes - taxonomic class which contains the cartilaginous fishes

Chop – locally generated waves, have a period of 1-10 seconds

Chronometer - a time piece which was frequently used in the 1700's to determine the longitude of vessels at sea

Choanocytes - flagellated cells that are responsible for creating currents in feeding sponges (synonym: collar cells)

Chromatophore - specialized cell which are used to change the color of a given animal

Ciguatera - condition caused by the ingestion of toxic fish flesh, found mainly in the tropics Symptoms include neurological dysfunction, exhaustion, visual disturbance, inversion of senses, paralysis, loss of reflexes, and death. Causative organism is a dinoflagellate called Gambierdiscus toxicus which can bloom in high numbers

Ciliophora - phylum of protozoans that contains the ciliates (i.e. paramecium)

Cladogram - a pictorial representation used to illuminate evolutionary relationships

Classification - the system used in grouping organisms based on their structural and biochemical similarities

Clitellum - pronounced cylindrical glandular region of the body that plays an important role in reproduction of oligochaetes

Clupeidae - taxonomic family which contains herrings, shads, sardines, and menhaden

Cnidaria - phylum which contains the true jellyfish, hydroids, sea anemones and corals

Cnidoblast - cells that contains and creates nematocysts

Cnidocil - trigger that projects form the tip of an undischarged nematocysts

Coast - a large zone which is affected by the ocean processes. This boundary Includes marshes, sand dunes, cliffs inland of the shore and sand bars and troughs immediately offshore

Coelomate - have a true coelom. Fluid-filled cavity lying between the outer body wall and the gut is lined with tissue derived from the mesoderm

Coevolution - the predator evolving in response to adaptations of the prey, or vice versa

Cold core rings - form to the east of the stream spin counterclockwise and have cores filled with sea water derived from outside the Sargasso sea

Collar Cell - flagellated cells that are responsible for creating currents in feeding sponges (synonym: choanocytes)

Colloblasts - sticky retractile tentacle used to catch prey

Commensalism - relationship where one animal derives a benefit from a host without causing significant harm

Community- several populations, which occur in an area

Competition - refers to the interaction between organisms for a necessary and limiting resource

Conjugation - sexual reproduction used by paramecium

Constructive wave interference – crest and troughs coincide resulting in a building up of the crest and the deepening of the trough. This sometimes results in a rogue wave

Continental Shelf - the shallow gently sloping section of the continental margin that extends from the shore to the point where the slope gets steeper

Continental Slope - the steeper seaward section of the continental margin

Contractile vacuole - removes excess water to keep osmotic balance in the paramecium and other protozoans

Controlled Experiment - additional variables that might affect the experiment are under the control of the researcher

Copepods - the primary herbivores in the sea; dominate plankton net collections. Belong to the phylum Arthropoda

Coquina rock - naturally occurring rock in southeast North Carolina which is composed of compressed sandstone

Corer - hollow metal tube pushed into the sediment. Upon retrieval the core is extracted intact and stored for future analysis

Coryphaenidae - taxonomic family which contains the Dolphinfish

Cosmogenous sediment - tiny grains that originate from outer space and tend to be mixed into terrigenous and biogenic sediment

Countershading - method of camouflage used by fishes, the dorsal side is a dark blue, and the ventral surface is a pale white

Countercurrent exchanger - network of closely associated capillaries found in their circulatory system, which permits some fishes to be slightly warm-blooded (Increased swimming efficiency) synonym (rete mirabile)

Crainovertebral joint - joint between the cranium and vertebra which allows for an increased gape and larger prey items

Crepuscular period - time of day with low light conditions, i.e: dawn and dusk

Crystalline style - digestive rod found in some bivalves, used for digestion

Ctenidia - comb-like molluscan gills which have cilia. Used for respiration and food collection

Ctenophora - phylum containing the comb jellies

Cubozoa - class of cnidarians which contains the box jellies

Cydippid larvae - larvae of ctenophores

Cynoglossidae - taxonomic family in the order Pleuronectiformes which contains the Tonguefish

Cytoproct - a permanent site in the cell wall of paramecium where waste is eliminated

Cytostome - associated with the oral groove in paramecium and helps in creating food vacuoles which digest food and distribute it in the cytoplasm

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D

Dactylozooids - polyps found in hydroid used for defense

Declination - depending on the angle between the earth's axis and the moon

Deep scattering layer - area of the water column where mesopelagic animals concentrate. This group of animals migrates vertically each night towards surface waters

Deep-water waves – bottom interactions are absent since the wave base is above the sea floor

Delta front - grades seaward from the delta plain and is essentially the shoreline

Delta plain - flat lowland that lies above sea level and is drained by a network of tributaries. Usually composed of sequences of flat-lying beds of sand and mud. Collectively referred to as topset beds

Demersal - concerning the bottom. Animals that are associated with the bottom but do not live on it. I.e. cods

Demospongiae - class of sponges. Spicules are made of silicon dioxide

Deposit feeders - an animal that feeds on organic material on or in the bottom (i.e. polychaete)

Desiccation - drying out, or dealing with water loss

Destructive wave interference – the crest of one wave coincides with the trough of another wave, if the two waves are of equal size it results in a cancellation

Detritus - broken down organic material

Deutrostomes - embryo development type which includes the bryozoans, echinoderms, and chordates

Dextral coiling - gastropod shell that coils to the right

  1. Dextral - term used when referring to right-eyed flounders

Diatom - unicellular phytoplankton that can form large colonial groups, test is made of silicon dioxide

Diodontidae - taxonomic family in the order Tetraodontiformes which contains the Porcupinefish

Dioecious - the parents are of 2 different sexes

Diploblastic - organisms that have two distinct germ (cell) layers

Dispersion (Wave) - waves begin to sorting themselves according to celerity, this process produces a regular swell

Disphotic - marginal amounts of light, not enough for photosynthesis to occur

Diurnal - tidal cycle which has 1 high tide and 1 low tide per day

Dive Reflex - physiological responses that diving marine mammals undergo during deep dives

Doldrums - rising air at the equator

Dune field - barrier island feature with the regular or irregular formation of dunes due to sea breezes blowing wind landward

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E

Echeneididae - taxonomic family which contains the Sharksuckers and Remoras

Echolocation - precise SONAR system used by marine mammals for locating prey and navigation

Ecology - The science that treats the interrelationships existing between organisms and their environments and among other groups of organisms

Ecosystem - a series of communities and the surrounding environment

Ectoderm - outer layer or skin

Ectoparasites - parasites which occur externally

Ectothermic - organisms which have an internal body temperature that conforms to the environment (synonym: poikilotherm )

Ekman spiral - model of the effect on water of wind blowing over the ocean. Due to the Coriolis effect the net transport of water in the northern hemisphere is ninety degrees to the right

El Nino - a southward-flowing nutrient poor current of warm water off the coast of western South America, caused by a breakdown of the trade wind circulation

Elasmobranchii - subclass of Chondrichthyes which contains the sharks, skates and rays

Elopidae - taxonomic family which contains tarpon and ladyfish

Endoderm - inner layer of cells

Endoparasites - parasites which occur internally

Endothermic - organisms which regulate their internal body temperature regardless of the environment (synonym: homeotherm) )

Engraulidae - taxonomic family which contains the anchovies

Ephippidae - taxonomic family which contains the Spadefish

Epidermis - outer layer or skin

Epifauna - animals that lives on the bottom

Epipelagic - the pelagic environment from the surface to a depth of 100-200 meters

Epitokes (epitoky) - individuals that are found in the annelids, theses organisms are given the task of reproduction. Some individuals bud epitokes from the body and remain in the habitat

Equatorial low pressure - intense heating and high moisture content makes the air less dense. Rising air produces a convergence at the surface into which air flows and rises.

Equilibrium (k-selected) - animals with long life spans, long development time to reach sexual maturity and few reproductions per year.

Esca - modified lure which is used by frogfishes and goosefishes to entice prey. Usually attached to an illicium

Eukaryote - cells which contain membrane bound organelles and a distinct nucleus

Euryhaline - animals which can tolerate a wide range of salinities. Antonym: stenohaline

Eversible proboscis - structure with jaws at the end that can extend out of the body

Evolution - a change in the genetic makeup of a population; occurs when natural selection favors some individual characteristics over others

Exocoetidae - taxonomic family which contains the Flyingfishes and Halfbeaks

Experiment - an artificially created situation that is used to test a hypothesis

Extant - living species

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F

Fecundity - term used when referring to a female's reproductive output

Fetch - the area which wind blows, creating waves

Filter feeder - an animal that feeds on suspended organic material by actively moving water through its tissue (i.e. sea squirt)

Fistulariidae - taxonomic family which contains the Cornetfishes

Flame bulbs - structures that are found in the protonephridia that are used to clean the blood

Fluke - fin used to propel marine mammals through the water

Foraminifera - phylum of protozoans which contains animals that dominate the benthos and have tests made of calcium carbonate

Foresets - the delta front which is composed of thick sands and silts. The foresets grade into the prodelta

Fugu - delicacy in Japan prepared by specially licensed chefs which originates from the meat of puffers

Fundulidae - taxonomic family which contains the Killifishes

Fungi - kingdom of multicellular organisms, no photosynthesis, nutrition by absorption (i.e. Mushrooms)

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G

Gadidae - taxonomic family which contains the cods and hakes

Gametes - reproductive products (i.e. - sperm and eggs)

Ganglia - several nerve cells that have fused together to form a primitive central processing area

Gastrodermis - inner lining of the digestive system (synonym: endoderm)

Gastropoda - class of molluscs which contains snails and slugs

Gastrozooids - polyps found in hydroid used for feeding and digestion

Gemmules - created by freshwater sponges and used as seeds to create new sponges after a period of dormancy

Geostrophic flow - a current in balance between the Coriolis deflection and gravity or pressure gradient

Germ layer - a group of cells that behave as a unit during embryonic development and give rise to distinctly different tissue/organ systems as an adult

Gerreidae - taxonomic family which contains the Mojarras

Glacial till - unsorted deposits of boulders, gravel, sand, and mud

Gobiidae - taxonomic family which contains the Gobies

Gonochoristic - the parents are of 2 different sexes (synonym: dioecious)

Gonozooids - hydroid polyps used for reproduction

Groins - man made structures built on barrier islands which are much smaller and cheaper than jetties. Perpendicularly positioned on eroding beaches to trap sand artificially and promote accretion

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H

Habitat - the environment where an organism occurs; habitat can vary in temperature, salinity, tides, and currents

Hadalpelagic - an area of the pelagic environment at an approximate depth of 6,000 m - 10,000 m. This area is aphotic

Haemulidae - taxonomic family which contains the Grunts

Halocline - an area in the water column of rapidly changing salinity

Heliozoa - phylum of protozoans, strictly freshwater (not covered in class)

Herbivores - eat strictly producers

Hermaphrodites - an animal that has both male and female sex organs

Hermatypic - corals which are reef building

Hemichordata - subphylum which contains the acorn worms

Heterocercal - caudal fin where one lobe is larger than the other. Many sharks use this arrangement for added lift

Heterotroph - an organism that obtains energy from organic matter

Hexactinellida - class of sponges. Spicules are six pointed and have a lattice-like structure (made of silicon dioxide)

High pressure zone - is where air pressure is higher than in surrounding area because of cooling or lower moisture content

Hirudin - chemical excreted by the salivary glands of leeches which prevents the blood from coagulating

Hirudinea - class of annelids which contains the leeches

Hjulstrom diagram - graph which shows the average current velocities for erosion, transportation and deposition

Holdfast - structures which algae use for attachment to substrate

Holocentridae - taxonomic family which contains the Squirrelfishes

Holocephali - subclass of Chondrichthyes which contains the ratfishes or chimaeras

Holoplankton - spend their entire life in the plankton. Includes: ctenophores, copepods, isopods, and amphipods

Homeotherm - organisms which regulate their internal body temperature regardless of the environment (synonym: endothermic)

Homocercal - caudal fin where both lobes are of equal size. Ideal for providing the maximum amount of thrust

Horse latitudes - sinking air at 30° N and 30° S

Hydrostatic skeleton - a fluid system permitting muscles to be stretched and return back to their original length following a contraction

Hydroida - order in the class Hydrozoa in the phylum Cnidaria. Contains the hydroids

Hydrothermal vents - communities found in areas of geological activity where cracks in the earth's crust release sulfides or methane. Communities with a reliance on chemosymbiotic bacteria colonize these deep sea habitats

Hydrozoa - class of cnidarians which contains the hydroids

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I

Ichthyology - the scientific study of fishes

Illicium - a modified dorsal spine used in goosefishes and frogfishes. An esca is located on the tip and is use to entice prey

Infauna - animals that live in the bottom

Infralittoral - the lower intertidal, exposed to air twice a month during spring low tides

Internal waves - occur in a stratified water column and travel a very slow speeds. Periods are measured in minutes, wavelengths in hundreds of meters and the waves can reach sizes of 330 feet

Interspecific - in between two different species

Intertidal - the area from the highest high tide to the lowest low tide (synonym: littoral)

Intraspecific - within the same species

Istiophoridae - taxonomic family which used to contain the Billfishes (currently listed as a sub-family)

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J

Jetties - man made structures built to prevent the deposition of sediment in harbor mouths, estuaries, or tidal inlets

K

Keystone species - a single species, which has a controlling effect on the community in which it lives.

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L

La Nina - the intensification of normal Pacific atmospheric and oceanic circulation

Labial palps - structures found in bivalves, which are responsible for sorting food material before it enters the mouth

Labridae - taxonomic family which contains the Wrasses

Labriform swimming - swimming method used by the labrids. Flapping of the pectoral fins

Lamniformes - taxonomic order which contains the typical sharks. I.e.: Megamouth, white, blue, nurse, hammerhead, basking, etc.

Langmuir circulation - a series of parallel , counter-rotating circulation cells with long axes aligned to the direction of wind flow

Larvae - independent morphological stages that arise from fertilized eggs. Must undergo profound changes before becoming an adult

Lateral line - rows of small tubes or pores which are sensitive to pressure changes (vibrations in the water)

Lecithotrophic larvae - larvae that posses a yolk-sac and generally spend a shorter duration in the plankton. Also, produced in fewer numbers than planktotrophic larvae

Leptocephalus larvae - Planktonic, thin and transparent larvae which is only used by the tarpon, ladyfish and Anguilliformes

Limiting resources - the resources which are in short supply are called

Littoral - the area from the highest high tide to the lowest low tide (synonym: intertidal)

Lobata - order of ctenophores

Longshore currents - currents that move parallel to the beach

Lophiidae - taxonomic family which contains the goosefishes

Lophiiformes - taxonomic order which contains the goosefishes and frogfishes

Low pressure zone - air density is lower than in surrounding areas because the air is warmer or has a higher moisture content.

Lutjanidae - taxonomic family which contains the Snappers

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M

Mackerel Sharks - loose grouping of sharks which contains the Basking, Megamouth, White and Mako sharks

Macronuclei - cell nucleus that contains many copies of the genome and is responsible for day to day activities (found in paramecium)

Malacanthidae - taxonomic family which contains the Tilefishes

Mantle - the body wall that enclose the body cavity in most Molluscs

Meiofauna - animals that live in between sand grains

Melanophore - pigment spots which are common on larval fishes

Melon - fatty structure found on the head of echolocating marine mammals which focuses and directs sound waves

Meroplankton - spend only part of their life in the plankton. Includes various larval stages

Mesenteries - sheets of tissue which are used to partition the digestive cavity of cnidarians (synonym: septa)

Mesoderm - occurs between the endoderm and ectoderm. Found in triploblastic animals

Mesoglea - non living cell layer found in cnidarians, jelly consistency which can range from thick and fibrous, to almost absent

Mesopelagic zone - the pelagic environment from a depth of approximately 200 m to 1,00 m. This area of the water column is disphotic

Mesohyl - is non-living cell layer found in sponges and made of collagen. Contains living cells which are collectively referred to as mesenchyme cells

Metamerism (metameric segmentation) - repeating of the same structures in each segment. Found in annelids

Metamorphosis - abrupt morphological, physiological, and ecological change

Metazoan - multicellular organisms

Micronuclei - cell nucleus that has very little to do with the functions of the organism. Essential in sexual reproduction (found in paramecium)

Midlittoral - the true intertidal, the area from average high tide to average low tide. Contains the greatest diversity of animals in the intertidal

Mixed tides - two high and two low tides each day with different tidal ranges

Molidae - taxonomic family in the order Tetraodontiformes which contains the Molas or Sunfishes

Mollusca - phylum of invertebrates which contains a diverse assemblage, i.e. - clams, oysters, squid, limpets, whelks, and sea hares

Monera - kingdom of single celled, prokaryote organisms (i.e. Cyanobacteria (blue-green algae))

Moronidae - taxonomic family which contains Striped Bass

Mugilidae - taxonomic family which contains the Mullets

Muller's larvae - larval stage of marine turbellarians (flatworms)

Multiple fission - a type of asexual reproduction that result in several individuals

Mustelidae - taxonomic family in the order Carnivora which contains the Sea otter

Mutualism - relationship where both members of the association benefit

Mysticeti - suborder in the taxonomic order Cetacea which contains the Baleen whales

Myxinidae - taxonomic family which contains the hagfish

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N

Natural selection - production of offspring by the best-adapted individuals in a population

Naturalist - an individual who is concerned with the scientific study of nature. Commonly carried by ships in the 1700 and 1800's

Neap tide - lower than average high tide and higher than average low tide. Occurs twice a month during the first and third quarter of the moon

Nearshore current - currents that form due to wave-setup and move perpendicular to the beach

Nekton – animals that have the ability to oppose currents

Nematocysts - complex intracellular organelles (capable of stinging) of cnidarians that are used for feeding and defense

Neoteny - larval stages which develop mature gonads and reproduce instead of undergoing a metamorphosis into an adult

Nephridia - structure which are used to clean the blood and eliminate excretory waste (singular nephridium)

Neritic zone (coastal zone) - the pelagic environment above the continental shelf

Neuston - area of the water column or animals that live in the air/water interface

Niche - the role a species plays in the community

Nictitating membrane - structure found in predatory sharks that covers the eye for protection

Noctiluca - flagellated protozoan which is bioluminescence

Null hypothesis - the hypothesis which yields the default result. The hypothesis of no change

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O

Oceanic zone- the area of the pelagic environment beyond the shelf break

Oceanic trenches - the deepest part of the world's oceans

Ocelli - used as light receptors in the jellyfish.

Ocellus - eye-like spots found on the caudal area of fishes used as a false eye to avoid head attacks by predators (plural: ocelli)

Odobenidae - taxonomic family in the order Carnivora which contains the Walrus

Odontoceti - suborder in the taxonomic order Cetacea which contains the Toothed whales

Olfaction - an animals sense of smell

Oligochaeta - class of annelids that is comprised of mainly earthworms

Omnivores - generalists have a diverse diet

Ontogeny - term used when discussing the different stages of an animals life history and different development stages

Operculum - proteinaceous shield on the foot of gastropods used to seal the shell shut

Ophidiidae - taxonomic family which contains the cusk-eels

Opisthobranchia - subclass of gastropods in the phylum Mollusca contains the nudibranchs and sea hares

Opisthosoma - the last body segment in the pogonophorans. Has many segments and septa like polychaetes, these anchor the animal in the tube

Opportunistic (r-selected) - animals with short life spans, rapid development to sexual maturity and many reproductions per year

Oral groove - found in paramecium and acts as the mouth of the organism

Oral surface - area of an animal located near the mouth

Oscules - (singular: osculum) large openings, which allow water to exit the sponge

Osmoconformers - animals which have an internal ionic concentration identical to the surrounding water

Osmoregulators - animals which have the ability to control the internal ionic concentration of their tissues

Osphradium - structure used by some molluscs to determine both the chemical and sediment content of the water

Ostia - (singular ostium) microscopic openings that allow water to enter the sponge

Osteichthyes - taxonomic class which contains the bony fishes

Ostraciidae - taxonomic family in the order Tetraodontiformes which contains the Boxfishes

Ostracitoxin - toxin found in the boxfishes which originates in special club cells in lips & causes agglutination of red blood cells in other fishes

Ostracoderms - the first group of fishes to appear on earth. Possessed large protective plates and lacked jaws

Otarridae - taxonomic family in the order Carnivora which contains the Sea lions or eared seals

Otolith - calcified structures found in bony fishes that are used for hearing. Fishery biologist can use these structures to determine age and growth rate

Oviparity - method of reproduction in which the female deposits eggs after fertilization. I.e. skates

Oxygen minimum layer - area of the water column with very little oxygen found between 500-1000 meters. This area is present due to animal respiration and lack of an interchange between water masses with oxygen rich water

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P

Pallial line - area inside bivalve shells where the mantle attaches

Parapodia - lateral wings used for swimming in sea hares. Also, fleshly lobes which are supported by chitinous rods in annelids. Important in locomotion and respiration (singular: parapod)

Parasitism - the parasite benefits at a significant cost to the host

Pardaxin - chemical secreted by the Moses sole from the Red Sea which possibly repels sharks

Parenchyma - tissue that fills the space between the outer body wall and the endoderm of flatworms

Parenchymella - ciliated mouthless larva found in sponges

Parthenogenesis - eggs develop to adulthood in the absence of fertilization (some arthropods, and rotifers)

Pedal laceration - type of asexual reproduction in sea anemones. The base of the animal is separated from the body, each regenerating new animals

Pelagic - the area of the water column away from the ocean bottom

Pelagosphera - Large larvae (several mm.) that is long lived and can be dispersed over long distances, found in the sipunculans

Percichthyidae - taxonomic family which contains the striped basses and wreckfishes

Peristaltic muscle contractions - muscle contractions that move objects in a linear fashion down a tube

Petromyzontidae - taxonomic family which contains the lampreys

Phagocytosis - method of engulfing food most often used by amoeboid protozoans

Pharyngeal teeth - molarform teeth found in the throat of fishes used for grinding and creating sounds

Phocidae - taxonomic family in the order Carnivora which contains the Seals

Photophore - specialized organs which are responsible for producing light (see bioluminescence)

Physoclistous swimbladder - swimbladder which has special structures associated with the circulatory system A network of capillaries and gas gland allow the inflation and deflation of the swimbladder

Physostomous swimbladder - swimbladder which has a connection between the swimbladder and the gut. The swimbladder is inflated by gulping air at the surface and deflated by the relaxation of sphincter muscles causing a gas-spitting reflex. Usually found in ancestral soft-rayed fishes

Phytoplankton - the photosynthetic component of plankton consisting primarily of single celled algae and bacteria

Phylogenetic relationships - classification system based on evolutionary relationships

Pinnipedia - suborder in the taxonomic order Carnivora which contains the sea lions, seals, and walrus

Piscivore - eat strictly fish

Placental viviparity - Nutrients are supplied to the embryo directly from the mother via a umbilical cord

Placoderms - the first of group of fishes to possess well-developed jaws

Plankton - organisms that lack the ability to oppose wind and currents

Planktivorous - eat strictly plankton. I.e. herrings, anchovies, sardines, whale shark, and baleen whales

Planktotrophic larvae - larvae that are poorly prepared for life in the plankton. Lack a yolk-sac, and spend prolonged periods drifting in the plankton. Generally have a low survival rate

Plantae - multicellular, autotrophs (kingdom)

Planula larvae - ciliated larval stage found in the phylum Cnidaria

Plasmodium - protozoan that causes malaria

Pleuronectidae - taxonomic family in the order Pleuronectiformes which contains the Right-eye

Pleuronectiformes - taxonomic order which contains the Flatfishes

Plunging breaker – the wave steepens, curls, and collapses releasing the energy instantaneously. Found on steeper bottoms

Poikilotherm - organisms which have an internal body temperature that conforms to the environment (synonym: ectothermic)

Pogonophora - class of annelids that contains deep sea hydrothermal vent worms

Polar high pressure - cold, dry, dense air sinks to the surface and flows outward forming an area of divergence

Polychaeta - class of annelids which comprises the marine worms

Polygynous - sexual practice where males maintain a harem of several females for mating purposes

Polymerase chain reaction (PCR) - chemical reaction which makes copies of DNA that are created to examine changes in DNA

Polymorphism -animals that have more than one body morphology in the life cycle. Also, used when discussing different morphologies in a colonial animal

Polyplacophora - class of Molluscs which contains the chitons and limpets

Pomacanthidae - taxonomic family which contains the Angelfish

Pomacentridae - taxonomic family which contains the Damselfishes

Pomatomidae - taxonomic family which contains the Bluefishes

Population - all the species in a given area

Porifera - phylum which contains the sponges

Predation - is the act of one animal eating another

Priacanthidae - taxonomic family which contains the Bigeyes

Primary coasts - Rough and irregular coasts created by the scouring of glaciers, sediment deposits in the mouth of rivers, volcanic eruptions or the movement of the earth along faults

Prodelta - delta feature which occurs further offshore at the base of the foreset and is characterized by a flattened area. Composed of several layers of silts and clays collectively referred to as bottomset beds

Proglottid - the individual segment of a tapeworm, each containing both testes and ovaries

Prokaryote - primitive cells which lack membrane bound organelles and a distinct nucleus

Prosobranchia - subclass of gastropods in the phylum Mollusca which contains the shelled snails (i.e. - whelks, tulips)

Protandric - sequential hermaphrodite which changes from male to female (i.e. Eastern oyster)

Protogynous - sequential hermaphrodite which changes from female to male (i.e. Groupers)

Protostome - embryo development type which includes the annelids, molluscs, and arthropods

Protista - kingdom of single celled organisms, contains nucleus and internal subdivisions (i.e. dinoflagellates, foraminiferans radiolarians and protozoans)

Protonephridia - primitive kidneys

Pseudocoelomate - the region between the outer body wall and the endoderm is a fluid filled cavity

Pseudopodia - false feet which are formed in amoebas. Used for movement and prey capture

Pteraspidomorphi - taxonomic class which contains the hagfishes

Ptychodiscus - genus of a dinoflagellate that causes red tides

Pycnocline - an area in of the water column with a rapidly changing density

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Q

Qualitative sampling - sampling techniques used for examining the species composition of a given area. Trawls and dredges are commonly used for this sampling technique

Quantitative sampling - sampling techniques used to examine densities and abundance. Grabs are a common sampling technique

R

Rachycentridae - taxonomic family which contains Cobia

Radial symmetry – can be divided into 2 approximately equal halves by any cut that passes through the center of the organism

Radiozoa - phylum of protozoans which contains the radiolarians. Tests are made of silicon dioxide

Radula - firm ribbon composed of chitin and protein which has two rows of sharp chitinous teeth. By moving in a rasp like fashion material is gathered (found only in Molluscs)

Rajiformes - taxonomic order which contains the skates, rays, guitarfish and manta rays

Ram ventilation - respiratory method found in fast moving fishes. The act of swimming, forces water across the gills. These fish will die if they stop moving

Refraction (Wave) - different celerity across one wave crest causes the wave to bend to the shape of the shoreline

Requiem Sharks - loose grouping of sharks which contains the Bull, Whitetip, Reef, Tiger, and Blue sharks

Rete mirabile - network of closely associated capillaries found in their circulatory system, which permits some fishes to be slightly warm-blooded (Increased swimming efficiency) synonym (countercurrent exchange system)

Rhopalia - structures found around the margin of jellyfish, which contains the ocelli and statocyst

River dominated delta - fed by strong flowing freshwater and continental sediments. These deltas form in protected seas and terminate in well defined tributaries a characteristic birds foot shape

Rogue waves - abnormally large waves which are usually created through constructive wave interference

Rostral ampullary organ - structure which is found in the nose region of sturgeon and are used to sense the weak electrical currents of prey

Rotary wave - tidal phenomena discussed in the dynamic model of tides. High and low tide which circles around a central point

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S

Salmonidae - taxonomic family which contains the salmons, trouts, graylings, and whitefish

Salt marshes - low energy environments on the bayward side of the island where mud accumulates and salt marsh grasses grow

Sarcodinids - amoeboid protozoans, contains the foraminiferans and the radiozoans

Sarcopterygii - taxonomic subclass which contains the lobe-finned fishes (i.e.: Lungfish, coelacanth)

Sargasso sea - Found between the Bahamas and Azores. This is considered the center of the north Atlantic gyre

Saxitoxin - toxin released by dinoflagellates that cause red tides

Scaphopoda - class of molluscs that contains the tooth and tusk shells

Scaridae - taxonomic family which contains Parrotfishes

Schistosomiasis - disease caused by a fluke

Sciaenidae - taxonomic family which contains the Drums

Scientific method - set of procedures by which scientists learn about the natural world

Scolex - structure found in Cestodes that is studded with hooks or sucker to hold the animals position in the hosts gut

Scombridae - taxonomic family which contains the Mackerels

Scorpaenidae - taxonomic family which contains the Scorpionfishes, Pacific Rockfish and Ocean Perch

Scutes - raised scales found in the region of the caudal peduncle that increases the hydrodynamic efficiency of the caudal fin. Found in fast swimming fishes

Scyphozoa - class of cnidarians which contains the true jellyfish

Seawalls - man made structures built on the shore to protect beaches, roads, and bluffs

Secondary Coasts - are attacked and change by both processes from the land and the sea (i.e. barrier islands)

Sedentary - an organism that can move, but does such infrequently (i.e. clam)

Seiches – the back and forth sloshing of water in harbors, wave periods of tens of minutes to several hours (antonym: standing wave)

Semidiurnal tides - tidal cycle where there are 2 high tides and 2 low tides every day

Septa - sheets of tissue which are used to partition the digestive cavity of cnidarians. Also used to divide the body into segments in the annelids(synonym: mesenteries)

Sequential hermaphrodite - an animal which undergoes a sex change at specific size, social conditions or environmental conditions

Serranidae - taxonomic family which contains the Groupers and Sea Basses

Sessile - an organism that lives attached to one spot and does not move

Setae - structures found in the annelids associated with parapods. Can be sharp (protection), and aid in locomotion

Sexually dimorphic - the ability to determine sex through external characters, i.e.: size, color, or other structures

Shallow-water wave – bottom interactions are present since the bottom depth is less than ½ the wavelength

Shore - where the ocean meets land (i.e sandy beach)

Significant wave height – the average of the highest one third of all the waves present in an area

Simultaneous hermaphrodite - an animal which contains functional ovaries and testes

Sinistral coiling - gastropod shells that coil to the left

  1. Sinistral - term used when referring to left-eyed flounders

Siphonophora - order in the class Hydrozoa and in the phylum Cnidaria. Contains the Portuguese man-of-war

Sipuncula - phylum which contains the peanut worms

Sirenia - taxonomic order which contains the Manatees and dugongs

Sparidae - taxonomic family which contains the Porgies

Species – a reproductively isolated population of interbreeding organisms which produce viable offspring

Spermatophores - packets of sperm which are commonly used in invertebrates (i.e. squid, octopus)

Sphyraenidae - taxonomic family which contains the Barracudas

Spicules - hard skeleton structures of sponges, which can be made of calcium carbonate or silicon dioxide

Spilling breaker – the crest spills down the front of the wave continually breaking and losing energy across the surf zone. This is the most common type of breaker, which occur on sandy bottoms and a gentle sloping sea bottom

Spiracles - Openings on the head that bring water into the gill cavity. Method favored by skates and rays

Spiral valve - primitive adaptation which allows for increased digestive surface area in a compact digestive system

Spongocoel - the empty space of the sponge (main cavity)

Spring tide - higher than average high tide and lower than average low tide. Occurs twice a month during a new and full moon

Squaliformes - taxonomic order which contains the cookie cutter shark, dogfish, and angelsharks

Statocyst - found in the phylum Cnidaria. Used for orientation and as a pacemaker for bell contractions

Statolith - structure found in ctenophores that when used in conjunction with balancers helps determine the orientation of the animal

Stenohaline - animals which can only tolerate a narrow range of salinities. Antonym: Euryhaline

Stokes drift - the small amount of forward movement water makes through a passing wave

Stridulation - method used by fishes where pharyngeal teeth are used in creating grunt sounds, which are amplified by the swimbladder

Strobilation - the type of asexual reproduction which produces medusa in the scyphozoan lifecycle

Stromateidae - taxonomic family which contains the Butterfishes

Submarine canyon - a narrow , deep depression in the continental shelf formed by the erosion of rivers or glaciers before the shelf was submerged

Submarine ridge - underwater mountain range (i.e. Mid-Atlantic ridge)

Subtidal - the area from the lowest low tide to the deepest parts of the ocean

Succession - natural progression of communities

Suction feeding - method of feeding where the rapid opening of a large mouth draws a prey item into the predator's mouth

Supralittoral - upper intertidal (spray zone) covered with water twice a month during a spring tide

Surging breaker – flat low waves that never become oversteepened or break. Found in areas of the steepest beaches and much of the wave is reflected back into the sea (sea walls and sea cliffs)

Suspension feeder - an animal that passively feeds on particles suspended in the water column

Sverdrup - unit of measure = 1,000,000 m3/sec

Swash zone - the area of the sandy intertidal where the waves run up and down the beach

Swell – wave period of approximately 10-30 seconds

Swim Bladder - gas filled structure found in bony fishes used to counteract the density of their flesh. Allows control of buoyancy

Symbiotic associations - an association between two organisms

Syngnathidae - taxonomic family which contains the Sea Horses and Pipefishes

Synodontidae - taxonomic family which contains the lizardfishes

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T

Tapetum lucidum - reflective layer found in the eyes of nocturnal fishes, allows increased vision at night

Terrigenous sediment - produced by the weathering and erosion of rocks on land; typically sand and mud. This is the most common sedimentary deposit

Tests - protective exoskeleton made of varying substances

Tetraodontidae - taxonomic family in the order Tetraodontiformes which contains the Puffers

Tetraodontiformes - taxonomic order which contains the the ocean sunfish, triggerfishes, filefishes, puffers, burrfishes and boxfishes

Thermocline - is an area in the water column of rapidly changing water temperature

Thunniform swimming - swimming method used by Scombrids. Propulsion is accomplished by the caudal fin only

Tidal bore - wall of surging water in narrow, confined areas

Tidal period - the time needed for one high and low tide

Tidal range - the vertical distance between high and low tide

Tide dominated delta - The strong ebb and flood of tidal currents takes sediment and places it into a long linear submarine ridge and islands that fan out from the river mouth

Topset beds - Flat lowland that lies above sea level and is drained by a network of tributaries Usually composed of sequences of flat-lying beds of sand and mud (i.e Delta plain)

Torsion - the process of the visceral mass of gastropods spinning 90-180 degrees

Trematoda - class of parasitic flukes in the phylum platyhelminthes

Triglidae - taxonomic family which contains the Searobins

Triploblastic - organisms that have three distinct cell layers (ectoderm, endoderm, mesoderm)

Trochophore - early larval stage of molluscs. Also similar larvae found in the annelids and sipunculans

Trophosome - structure that contains the major organs of pogonophorans. The trophosome of all species contains closely packed bacteria and play a crucial role in nutrition

Tsunamis - wave periods from minutes to tens of minutes associated seismic activity

Turbellaria - class of free-living flatworms in the phylum platyhelminthes

Turbidites - sediments that are deposited in the deep sea by currents moving quickly down the continental slope. These sediments are usually terrigenous sediments

Turbidity - the amount of solid particles suspended in the water column

Two pump respiration - found in slow moving or sedentary, bottom orientated fish. Respiration is accomplished by expansion and contraction of the buccal and opercular cavities

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U

Unicellular – single cell (i.e. protozans)

Umbo - is the oldest part of the bivalve shell, located dorsally

Urns - specialized cells (found in sipunculans) that float in the coelom collecting waste products bringing them to a nephridia

Urochordata - subphylum which contains the tunicates (i.e. sea squirts)

Ursidae - taxonomic family in the order Carnivora which contains the Polar bear

Uterine Viviparity - mother secretes nutrient rich fluid (via uterus) which is taken up through the skin of the embryo. Common in Stingrays and Eagle Rays

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V

Veliger larvae - secondary larval stage of some molluscs

Vertebrata - subphylum of animals which contains the vertebrates, fish, amphibians, reptiles and mammals

Vestimentiferan - members of the class pogonophora, deep sea hydrothermal vent worms

Volcanic islands - rise singularly out of ocean through volcanic action

Volcanogenic sediment - particles that are ejected from volcanoes; ash is an example

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W

Walker circulation cell - circulation cell between a western Pacific low pressure and eastern Pacific high pressure

Warm core rings - form to the west of the stream, rings rotate clockwise and have a warm core of Sargasso sea water

Wave amplitude - half of the wave height, the distance the trough or crest distorts the level water surface.

Wave crest - highest point of a wave.

Wave dispersion - waves begin to sorting themselves according to celerity, this process produces a regular swell

Wave dominated deltas - These deltas have wave erosion and strong longshore currents that disperse the sediment away from the river mouth. This produces a relatively straight coast

Wave height - vertical distance between the crest and trough

Wave length - horizontal distance between two adjacent wave crests or wave troughs.

Wave period - time required for two successive wave crests to pass a fixed point.

Wave refraction - different celerity across one wave crest causes the wave to bend to the shape of the shoreline

Wave trough - lowest point of a wave

Western boundary intensification - due to the Earth’s rotation water is pressed against the western boundary of ocean basins. This squeezes the western arm of the gyre current and intensifies the current

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X

Xiphiidae - taxonomic family which contains the Swordfish and Billfishes

Y

Yolk-sac Viviparity - Eggs are produced and retained inside the mother. Shell disappears and young are retained until fully developed. Synonym: Ovoviviparity

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Z

Zooplankton - the heterotrophic animal and protozoan component of plankton

Zooxanthellae - dinoflagellate which forms a mutalistic relationship with reef building corals. Provides coral with energy through photosynthesis

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