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All of the following terms appear in the videos or articles for this tutorial on biodiversity distribution patterns. The terms are arranged here in alphabetical order, and nouns are given in just their singular form unless the plural of the term is unusual.

adaptation: a physical or behavioral trait of an organism that make it well-suited to its environment and more likely to survive and reproduce

bacteria: one-celled micro-organisms that are found in large numbers all over the world; some provide important services to humans, some cause diseases; bacteria is pural; singular is bacterium, and can refer to a single bacterial cell or a single species of bacteria

barrier: in general terms, an obstacle or obstruction; in the context of species distribution, a physical feature of the landscape such as a mountain range, river, or road that restricts the ability of organisms to move from one area to another

biodiversity: the variety of life on Earth or some specified geographic area of the planet; the diversity of life occurs at the genetic level, at the species level, at the ecosystem level, and in evolutionary lineages biogeography: the study of how species are distributed on

biomass: the weight (that is, the mass) of living organisms in a given area 

biotic: living; as opposed to non-living (abiotic)

dispersal: in general terms, to scatter or distribute something; as related to species, how they get from one location to another, extending into new ranges distribution: the geographical places or areas around the world where a given species lives; similar to the range of the species

estuary: a partly enclosed body of sea water into which one or more rivers flow; the resulting mix of fresh water and salt water results in a wide variety of salinities, including brackish water

evolutionary: related to evolution, the changes in heritable traits of a population over time

extremophile: an organism that can survive and thrive in extreme environments 

geologist: a scientist who studies the Earth and processes that shape the Earth over time

geyser: a hot spring that erupts periodically, shooting steam and hot water into the air

habitat: a general term for the type of environment in which an organism lives

introduced species: a species living outside its natural geographic range due to human activities

island biogeography: the study of which species occur on different islands, which is a function of the size of the island and its distance from other land, especially the nearest large island or continent

Lake Vostok: a body of water beneath the Antarctic ice sheet that remains liquid due to pressure from the weight of the ice above it as well as heat from the land below it

latitude: geographic coordinates that run parallel to the equator; for example, northern latitudes are north of the equator

monoculture: the agricultural production of a single crop species over a large area

parasitism: a type of symbiosis in which one organism (the parasite) benefits by living in or on the organism that is harmed (the host)

population: all the individuals of a particular species that live in a specific geographic area; a species may be made up of one or more populations

population size: the number of individuals in a particular population of organisms

productivity: in general terms, a measure of how much of something is produced; in ecological terms, a measure of the amount of photosynthesis taking place; in agricultural terms, a measure of the output or yield of crops

range: the geographic places or areas around the world in which a species lives; similar to the distribution of the species

species: a distinct type of organism 

species richness: the number of different species in a given geographic area

temperature regime: the pattern of temperatures in a given area; e.g., the average seasonal pattern, the daily high and low, the maximum high and low, etc.

terrestrial: pertaining to the land

tolerance range: the range of values for a particular environmental factor within which an organism can survive; the tolerance range for an environmental factor such as temperature or salinity varies among different species and can vary for an individual at different times of its life

tundra: a biome characterized by long, cold winters, short growing seasons, permafrost (permanently frozen soil below the surface), and few or no trees