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Glossary

T

temperate rain forest: a type of forest found in only a few places around the world, such as the Pacific temperate rain forest on the west coast of North America. These forests are often dominated by conifers adapted to wet climates and cool temperatures.

testes: the male reproductive organs that produce sperm and the male sex hormones, testicles.

testosterone: a steroid hormone produced by the testes and adrenal glands which is required for sperm production, the development of the male reproductive organs and the emergence of male secondary sexual characteristics.

the Big Easy: a colloquial name for New Orleans.

threatened species: a way to describe organisms that are likely in the near future to become endangered.

tipping point: the moment of critical mass, the threshold, the boiling point; the point when everyday things reach epidemic proportions.

toboggan ride: a ride usually on the snow involving a long, flat-bottomed, light sled typically made of thin boards curved up at one end with low handrails at the side.

toxicity: the capacity of a material or organism to cause harm to another living organism.

tradeoff: an exchange of one thing in return for another; especially relinquishment of one benefit or advantage for another regarded as more desirable.

tragedy of the commons: a term coined by Garrett Hardin describing the inexorable process of degradation of communal resources due to selfish self-interest of "free riders" who use or destroy more than their fair share of common property.

trait: a genetic feature or characteristic, such as hair color or blood type, that may be passed on from one generation to the next.

trawl net: a conical fishnet dragged through the water or, in the case of bottom trawl, along the seafloor. This is one of the most destructive forms of fishing.

trophic cascade: the domino effect of changes to the lower levels of a food web when the upper levels are removed e.g. Increases in prey populations when predators are removed.

tropical dry forest: a type of forest found near the equator that has distinct rainy and dry seasons. Many tropical dry forest plants are adapted to withstand high temperatures and seasonal droughts.

tropical rain forest: a type of wet forest found near the equator that harbors the richest diversity of terrestrial plant and animal species.

tsunami: a sea wave of local or distant origin that results from large-scale seafloor displacements associated with large earthquakes, major submarine slides or exploding volcanic islands.

tubeworms: members of the Phylum Annelida that live inside tubes of their own making.

turbidity: a measure of the amount of light scattered and absorbed by water because of the suspended matter in the water.


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