Visit Your Local PBS Station PBS Home PBS Home Programs A-Z TV Schedules Watch Video Donate Shop PBS Search PBS

Episodes
Dangerous Catch Dirty Secrets Additional Episodes
border
TV Schedules About the Project For Educators Feedback border
border
National Geographic's Strange Days on Planet Earth
Get Involved
Little changes... with big results. border
border
Strange Days on Planet Earth
border

Please note that links marked with Off-site Link are off-site links and will open in a new browser window.

PBS's Terms of Use.

Glossary

M

macroinvertebrates: organisms (without backbones) greater than 1 mm (.04 inches) long that can typically be seen with the naked eye.

malaria: an infective disease caused by sporozoan parasites that are transmitted through the bite of an infected Anopheles mosquito; marked by paroxysms of chills and fever.

manure: any animal waste or plant material used to fertilize land, especially animal feces.

marine ecologist: a scientist who studies the relationship between marine organisms and their environments.

marine protected area: regions of the ocean reserved by law or other means to protect part or the entire region. Currently less than .1 percent of the ocean is protected.

marine reserves: places in the ocean that are completely protected from uses that remove animals and plants or alter their habitats.

Marine Stewardship Council (MSC): an international organization that has developed standards emphasizing environmentally and socially responsible criteria to certify well-managed fisheries.

mass extinction: a catastrophic, widespread perturbation where major groups of species become extinct over a relatively short time compared to normal background extinctions e.g., the K-T event, 65 million years ago, correlated with the disappearance of the dinosaurs.

medical fraternity: the medical community.

methane: a flammable, hydrocarbon found in natural gas that can be produced by microorganisms in the absence of oxygen. Like carbon dioxide, this is a heat-trapping gas.

methyl mercury: a toxic form of mercury.

Miconia: a leafy plant from Central America that made its way to Hawai'i in the 1960s and became an invasive problem.

microbiologist: a specialist in dealing with microscopic forms of life.

microinvertebrates: those organisms that are less than 1 mm (0.04 inches) long and are best viewed through a microscope.

microorganism: a living organism too small to be seen with the naked eye. Bacteria, protozoans, viruses, microscopic algae and some types of fungi are all microorganisms.

migration: the movement of animals in response to seasonal changes or changes in the food supply. Examples of animals that migrate include ruby-throated hummingbirds, salmon, monarch butterflies, buffalo and elephants.

Mola mola: the giant ocean sunfish, a teleostean (bony) fish from the Tetraodontiform order and pufferfish relative that sports a distinctive disk-shaped, tailless body flanked by long dorsal and anal fins. Found in all tropical and temperate ocean basins it holds the record for world’s heaviest bony fish.

monitor lizards: any of various large tropical carnivorous lizards of Africa and Asia and Australia.

mutagens: agents, such as chemicals or radiation, that damage or alter genetic material (DNA) in cells.

mutation: a spontaneous change in the genetic information of a cell. Mutations can provide genetic diversity within populations and allow evolutionary change to occur, although many mutations are either neutral or harmful to an individual.

mycobacteriosis: a fish disease, called the “fish handler’s disease” because it can also infect people. A wasting disease that first affects internal organs, causes inflammation, tissue destruction and scarring of internal organs. Red lesions can be seen on the skin in later stages of this disease.

mycobacterium: A large genus of bacteria. One type of Mycobacterium causes leprosy, while others cause tuberculosis, in addition to the type that causes “Fish handler’s disease” (see the “mycobacteriosis” entry)


Site Credits   |   Privacy Policy
© Copyright National Geographic Television & Film. All rights reserved.