Marine Organisms

Marine Taxonomy

The process of biological classification is called TAXONOMY.

Originally, Aristole classified organisms by only exterior similarities. All organisms that fly would be classified as similar according to Aristole. Thus he would have placed bats and birds in the same category but would not have placed penguins in this group since they don't fly. His classification rationale is an artificial system of classification.

Today, organisms are classified by a natural system of classification which relies on structure, biochemical and physiological similarities. In the eighteenth-century, Swedish naturalist, Carolus Linnaeus, (Carl von Linné) devised a natural system of classification using three main categories or KINGDOMS, animal, vegetable and mineral. Of course the latter kingdom did not have living organisms.

Scientists expanded the first two Kingdoms to five kingdoms, monera (bacteria), protista, fungi, plantae and animalia. As scientists discovered a special group of bacteria that can live in extreme condidtions, a sixth Kingdom was identified, the Archaea.

There are five kingdoms that have similar organisms but the sixth, the protista, have both one-celled plants and one-celled animals.

The Kingdom Archaea contains bacteria that live in extreme environments of heat, high methane concentrations or anoxic conditions. They are sometimes called "extremophiles" for this reason. They are found in deep within sediments, in vent communities, deep in solid rock formations. Some scientists believe that they may make up more biomass than all other living organisms combined.

All organisms can be separated into two major categories, those whose cells do not have a nucleus, PROKARYOTE, and those whose cells do have a nucleus, EUKARYOTES.

The five kingdom system of classification.

The six kingdom system of classification.

Convergent evolution.

Click here to read about a gamma burst 450,000 years ago that probably wiped out much of the sea life in existence then.

The six kingdoms of living organisms.

Kingdoms: - Monera, Archaea, Protista, Fungi, Plantae, Animalia

Phyla - There are 11 phyla of animals on land and 28 phyla of animals in the sea.

There are no true Marine Amphibia nor are there many fungi. Some fungi associate with marine algae in the intertidal zone in a relationship that is similar but not identical to lichens on the land.







Naming the Herring gull.

Kingdom - Animalia,

Phylum - Chordata,

Sub-Phylum - Vertebrata,

Class - Aves,

Order - Charadriformes,

Family - Laridae,

Genus - Larus

Species - argentatus

Larus argentatus - the Herring gull

Click here to view Professor Dale Stanley's Power Point Presentation on Taxonomy

Click here to read about new species found in the deep Atlantic.

Cells and the Movement of Nutrients/Waste Products
into and out of Cells

A CELL - the smallest building block of living things. All cells are surrounded by a cell membrane, have protoplasm with embedded organelles for reproduction, for protein synthesis, for extraction of energy from carbohydrates, for storage, and for waste removal. Some cells have external organelles such as cilia or flagella for movement. Plant cells have chloroplasts which trap sunlight to combine carbon dioxide and water to form energy rich carbohydrates and release oxygen as a waste product in a process called photosynthesis. Some plant cells have an additional outer covering called a cell wall. Nutrients, oxygen and carbon dioxide are transported through the cell wall and the cell membrane by diffusion or by an energy-driven process of active transport.

Some cells have their nuclear material enclosed within a nuclear membrane. Others, such as bacteria, have no nuclear membrane.

ORGANISM - a living single cell or group of living cells. Single celled organisms without a nuclear membrane are called prokaryotic cells or prokaryotes, while single celled and multi-celled organisms with a nuclear membrane are called eukaryotic cells or eukaryotes.

Multi-celled organisms have a division of labor among the cells, some involved in reproduction, some in movement, some in sensory activities, some in circulation, some in structure. Cells having the same purpose, i.e., movement, are called tissue. In this case muscle tissue. Tissues are sometimes organized into organs such as a muscle, and organs are sometimes organized into systems such as the circulatory system. Systems are organized into an organism. The failure of one system will have a negative effect on the entire organism.

SPECIES - a group of organisms with the same unique characteristics, i.e., Homo sapiens, humans or Glyptocephalus cynoglossus, the witch flounder as opposed to the Glyptocephalus zachirus, the rex sole.

Organisms are classified into taxonomic groups or in a hierarchy that goes from the general to the very specific or the species level. Classifications include 6 kingdoms, phyla, subphyla, class, order, family, genus and, finally, species. This system of identification makes each species unique.


Bacterial cells are prokaryotic cells that degrade organic matter and return it to inorganic nutirents. Cyano-bacteria (blue-green algae) are capable of photosynthesis.
  • Synechococcus, a cyano-bacteria, has little more than photosynthetic apparatus in it with a variant type of chlorophyll.

  • Some bacteria are capable of chemosynthesis using hydrogen sulfide or methane to produce engergy-rich compounds. These organisms are frequently the base of a food pyramid and are the only initial source of energy for organisms higher in the food web. These bacteria are the producers in the food web.

    The Archaea, also prokaryotes, are bacteria-like organisms that have the capability of producing enzyme systems not normally found in bacteria. They live in extreme environments including deep sediments in the ocean and in rock formations deep in the earth. These organisms have attracted the attention of both marine and land biologists.

    Bacteria are frequently infected with even smaller viruses (bacteriophages) that can only reproduce within the cells of organisms such as bacteria. Viruses take over the biological activities within the cell by substituting their RNA for the host's RNA.

    Some viruses (pycoviruses) infect phytoplankton cells.

    Viruses are so small that 100 million can exist in one milliliter of sea water or 3 billion per ounce of sea water.


    PHYTOPLANKTON (Part of the Protista Kingdom) - UNICELLULAR ALGAE


    Click here to read about the decoding of the DNA of a diatom, Thalassiosira pseudonana

    Search is on for killer plankton Puzzling sea life malady

    Michael McCabe, Chronicle Staff Writer

    Wednesday, May 8, 2002

    Marine scientists are carefully sampling the waters off Monterey this week for signs that a mysterious species of plankton could suddenly bloom and begin poisoning marine mammals, fish, sea birds -- and possibly humans.

    Hundreds of California sea lions, common dolphins and other marine mammals and sea birds have become ill or died on the southern and central California coast during the past two months.

    In recent days, at least one northern fur seal was discovered stranded and ill in the Monterey Bay area, suggesting that a plankton bloom there has already become toxic enough to sicken animals, scientists believe.

    The culprit is a diatom of the genus Pseudo-nitzschi, a microscopic single- celled plant that under certain conditions can produce domoic acid, a deadly nerve toxin.

    Recognizing the danger, the California Department of Health Services has issued several warnings to avoid eating all sport-harvested species of bivalve shellfish. The quarantine area is in effect for the entire California coast, including bays and estuaries. A separate health advisory for the San Luis Obispo coast warns people to avoid eating the dark-colored organs of anchovies, sardines and crab.

    There is no direct threat to humans unless they forage along the coast for small fish or shellfish and ingest them in great numbers, according to scientists.

    The chief threat is believed to come from anchovies which eat the diatoms and can pass the toxins on up the food chain, to larger fish, birds and marine mammals.

    There have been no reports of humans becoming ill caused by the toxins in California. All fish and shellfish sold in commercial stores and markets are safe to eat because they are carefully monitored by the state, said Raphael Kudela, an oceanographer at UC Santa Cruz and one of the chief investigators into the domoic acid phenomenon.

    The Marine Mammal Center in Sausalito has received 27 seriously ill sea lions from the Santa Barbara Marine Mammal Center. Southern California wildlife rescuers said they have been unable to keep pace with the problem.

    "There are so many sick and dead mammals on beaches that the system is overloaded," said John Heyning, curator of marine mammals at the Natural History Museum of Los Angeles County. "I suspect the numbers are going to rise, but you have to keep in mind that there are so many of these marine mammals we are not looking for them to become endangered because of this."

    Four of the 27 sea lions transferred to the Sausalito center have died. Clinical symptoms of domoic acid poisoning have been found in all the transferred animals, said Kathryn Zagzebski, stranding manager at the center.

    The diatoms are a naturally occurring organism that goes virtually unnoticed unless conditions are perfect for them to bloom. And even if they do bloom, they may not always become toxic enough to cause problems, said William Cochlan, senior research scientist at the Romberg Tiburon Center for Environmental Studies at San Francisco State University.

    There have been outbreaks of toxic algae many times in the past, scientists now believe. Some suspect that the phenomenon can be traced all the way back to biblical times. In 1998, the deaths of more than 400 sea lions in one month off Central California were attributed to this particular diatom phytoplankton.

    "We now suspect that domoic acid poisoning was also the cause of a massive bird poisoning in 1961, which resulted in birds acting as if they were intoxicated," Cochlan said.

    That event is believed by some scientists to have been part of the inspiration behind the fictional marauding birds of Alfred Hitchcock's 1961 classic, "The Birds."

    In humans, high doses of the toxin can cause permanent memory loss and death, Cochlan said. In 1987, he added, three people died and 104 others became ill in Prince Edward Island, Canada, after eating blue mussels carrying the domoic acid.

    "The two big questions we are trying to answer now is what causes these toxic species to bloom along the central coast, and even when these diatoms do bloom, why don't they always produce domoic acid," Cochlan said.

    This latest outbreak is not a so-called red tide invasion, marine scientists said, noting that it is not red and has nothing to do with tides.

    Nor is there any way to turn it back.

    "It's a natural phenomenon, and we can't stop it," said Heyning. "We can only hope to find out what is going on, and we probably won't get all the answers for months, if ever."

    E-mail Michael McCabe at




  • Very little is know about these organisms. They possess filamentous supporting structures made of silica yet they have one or two flagella. They are more closely related to dinos than diatoms and are primitive.

  • These planktonic cells are the smallest known phytoplankton. Until recently they were unknown and when observed under a microscope were thought to be suspended sediments. They are now considered to be responsible for 70% of all photosynthetic activity in the open ocean.

  • These organisms derive their name from "pico" which means "a trillionth". They measure from 0.2-2 micrometers or 4-40 millionths of an inch. 100,000 of these organisms can exist in one milliliter of sea water.

    MULTICELLULAR ALGAE - non-vascular plants


    • blades, stipes, holdfasts and gas bladders form the plant, no roots or vessels, nutrients, gases and wastes are moved in and out by osmosis or active transport, flexible in strong surf zone and frequently covered with a mucous to protect from dehydration

    CHLOROPHYTES green seaweed, can tolerate urban waters, surface plants with no accessory pigments, lettuce like Ulva

    PHAEOPHYTES brown seaweed, kelps, 130 ft. long, accessory pigment is fucoxanthin allowing growth at greater depths than chlorophytes, Macrocystis, Sargassum

    RHODOPHYTES most seaweeds are red algae, usually in low latitude waters, accessory pigments are phycobilins allowing rhodophytes to grow in extremely low light sources but some grow at surfaces which may suggest that the accessory pigments shade the plant, Lithophyllum looks like a rock and has calcium carbonate within its tissues, Lithothamnion is a coral community red algae and as such is called a coralline algae


    • vascular plants SEA GRASSES, exist in salt marshes and in the intertidal zone. There are 58 species of sea grasses in the sea including Spartina, (cordgrasses), are important as a food source, while upland grasses such as pickleweed, seaoats, and salt grass also stabilize dunes.

    • Sea grasses grow in the shallow water of estuaries, bays, salt marshes and beaches. These include turtle grases, Thalassia, and eelgrasses, Zostera. Other grases include widgeon grass, Ruppia, manatee grass, Syringodium, and shoal grass, Halodule.

    • Phytoplankton take up residence on some of these grasses, while some zooplankton graze on these grasses.

      Click here to read about the importance of sea oats.

      Phragmites australis

      Phragmites are commonly found in marshlands adjacent to brackish estuary waters. There were common phragmites that had a smooth, shiny stem; easily bent; did not have plants growing close to one another; produced sparse flowers; were reddish at the bottom in spring and summer.

      These phragmites have been replaced along the east coast by a non-native species from Europe which have different traits. This species has been identified as type M phragmites. They grow densely inhibiting the grow of other plants in the marsh. They have a rhizome root system and reproduce radiply. Their stems are rough and ridged; not easily bent; and tan at the bottom.

      Click here to see Phragmites communis

      Click here to see more about Phragmites australis.


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