Glossary
Adaptive radiation	the evolution of a single ancestor species into several new species within a relatively short period of time and in a certain geographic area. The plants and animals of the Galápagos Islands are a result of adaptive radiation, where one plant or one animal species diversified into many species that fill a variety of ecological roles. For example, more than a dozen species of finches evolved from a single founding species that colonized the islands from the mainland of South America.
Arboreal	living predominantly or entirely in trees
Atoll	a ring-shaped coral reef or string of coral islands, usually enclosing a shallow lagoon
Biodiversity	the variety of life on Earth and the interconnections among living things
Biogeography	the study of living systems and their distribution. Biogeography is important to the study of the Earth’s biodiversity because it helps with understanding where animals and plants live, where they don’t, and why.
Biotic	refers to the living components of the environment (such as plants, animals, and fungi) that affect ecological functions
Boreal	pertaining to the north
Brackish	slightly salty or briny. Brackish water is saltier than fresh water but less salty than seawater.
Bycatch	fishes, or any other animals, that are accidentally caught in fishing gear
Community	a characteristic group of plants and animals living and interacting with one another in a specific region under similar environmental conditions
Deforestation	the large-scale removal of trees from a habitat dominated by forest
Echolocation	the sonar-like ability used by bats, dolphins, and other animals to detect objects. Using echolocation, the animal emits high-pitched sounds that reflect off of an object and return to the ears or other sensory receptors.
Ecological or ecosystem services	valuable services provided by natural systems. Examples of ecological services include flood control, air purification, and climate control.
Ecoregion	a geographically distinct area of land that is characterized by a distinctive climate, ecological features, and plant and animal communities. The Klamath-Siskiyou Coniferous Forests in the U.S. Pacific Northwest is an example of an ecoregion.
Ecosystem	a community of plants, animals, and microorganisms that are linked by energy and nutrient flows and that interact with each other and with the physical environment. Rain forests, deserts, coral reefs, grasslands, and a rotting log are all examples of ecosystems.
Endangered species	a species threatened with extinction. The Florida panther and the California condor are endangered species.
Endemic species	species that naturally occurs in only one area or region. For example, the redfin darter is a fish endemic to the rivers of the Ozark forests, and the Joshua tree is a plant endemic to the Mojave Desert.
Ephemeral	lasting for a very short time
Evolution	the process of change in the traits of organisms or populations over time. Evolution, through the process of natural selection, can lead to the formation of new species.
Extinct	refers to a species that no longer exists. Local extinction occurs when every member of a particular population has died. Global extinction occurs when every member of a species has died. The passenger pigeon and the dodo are examples of globally extinct birds.
Fauna	the animals that live in a particular area
Flora	the plants that live in a particular area
Fragmentation	the breaking up of large habitats into smaller, isolated chunks. Fragmentation is one of the main forms of habitat destruction, which is the primary reason biodiversity is in decline.
Geography	the science of space and place that brings together Earth’s physical and human dimensions in the integrated study of people, places, and environments
Global warming	the process by which the Earth’s atmosphere is warming because of the release of “greenhouse gases,” such as carbon dioxide. These gases are released into the air from burning gas, oil, coal, wood, and other resources and trap heat in an action similar to that of the walls of a greenhouse.
Grasslands	areas of abundant grasses and shrubs with very few trees, like prairies or meadows. Grasslands can be found in many places. Large temperate grasslands occur naturally in central North America (prairies), southern South America (pampas), central Asia (steppes), southern Africa (savannas), and Australia.
Greenhouse effect	the trapping of heat in the Earth’s atmosphere by certain gases such as carbon dioxide, methane, and nitrous oxide. Some scientists predict that the temperature and sea level rise associated with global warming could adversely affect biodiversity.
Guano	manure from animals like birds and bats
Habitat	the area in which an animal, plant, or microorganism lives and finds the nutrients, water, sunlight, shelter, living space, and other essentials it needs to survive. Habitat loss, which includes the destruction, degradation, and fragmentation of habitats, is the primary cause of biodiversity loss.
Introduced species	a species that does not naturally occur in an area. Also called alien, exotic, or non-native species, these invaders can cause major problems for native plants and animals.
Invertebrate	an organism that does not have a backbone
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.
Montane	pertaining to a mountainous region
Native species	a species that occurs naturally in an area or habitat. Also called indigenous species.
Natural selection	the process by which genetic traits are passed on to each successive generation. Over time, natural selection helps species become better adapted to their environment. Also known as “survival of the fittest,” natural selection is the driving force behind the process of evolution.
Pesticides	chemicals that kill or inhibit the growth of organisms that people consider undesirable. Fungicides (which kill fungi), herbicides (which kill plants), and insecticides (which kill insects) are types of pesticides.
Phenomena	unusual and/or significant occurrences. For example, the yearly migration of monarch butterflies from central Mexico into the United States and Canada is a natural phenomenon.
Phytoplankton	the plant plankton and primary producers in aquatic ecosystems
Pioneer plant	a plant species that appears early in the cycle of vegetation succession. These pioneer plants have characteristics that particularly suit their role in the early stages of succession, such as a rapid growth rate and the ability to produce large amounts of small, easily dispersed seeds.
Poaching	hunting, trapping, or fishing illegally
Range	the area in which an organism may travel in its lifetime. Range also refers to the geographic distribution of a particular species.
Realm	a region of the Earth that harbors similar groups of species based on a shared biogeographical history. For example, while primates are found in many parts of the world, all monkeys found with prehensile tails are only found in the Neotropic realm. The Earth is made up of eight realms.
Reintroduce	to return members of a species to their historical range. This strategy is sometimes used when a species has become locally extinct or if its population is threatened.
Relict species	a species that has survived while other related ones have become extinct. A relict species may be one that had a wider range but is now found only in particular areas (like the European white elm tree in western Siberia), or it may have survived relatively unchanged from an older period when other kinds of species went extinct (such as horseshoe crabs).
Restoration	the repair of ecological damage to an ecosystem so that it is close to the natural condition prior to a disturbance and it can function as a normal self-regulating system. This is done through processes such as chemical cleanups, revegetation, and the reintroduction of native species.
Riparian	pertaining to the banks of a river or other body of fresh water
Savanna	a type of grassland with widely spaced trees and a blanket of grasses that require a lot of light. Rainfall usually occurs in the warmer, summer months with a dry period of between two to eight months. Fires are typical across savannas during drier months and occur at intervals from one to 50 years.
Slash and burn agriculture	an agricultural system in which farmers periodically clear land for farming by cutting and burning patches of forest. Traditionally, patches used for agriculture were allowed to revert to forests for a number of years before being replanted, causing minimal impact. Today, however, intensive slash and burn agriculture damages many tropical forest ecosystems.
Specialist species	a species that has a narrow ecological niche. For example, they may be able to live in only one type of habitat, tolerate only specific environmental conditions, or eat only a few types of food. The panda is a specialist species because over 95 percent of its diet consists only of bamboo.
Speciation	the process by which one or more populations of a species become genetically different enough to form a new species. The process often requires populations to be isolated for a long period of time.
Species	(1) a group of organisms that have a unique set of characteristics (like body shape and behavior) that distinguishes them from other organisms. If they reproduce, individuals within the same species can produce fertile offspring. (2) the basic unit of biological classification. Scientists refer to species using both their genus and species name. The house cat, for example, is called Felis catus.
Sustainable	meeting the needs of the present without diminishing the ability of people, other species, or future generations to survive.
Taiga	a type of coniferous evergreen forest, found in the subarctic areas of North America and Eurasia. Also known as a boreal forest
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 conifer trees adapted to wet climates and cool temperatures.
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.
Upwelling	an upward flow of cold, heavy deep-sea water caused as offshore currents draw away warm surface water. The deep-sea water of upwellings is generally rich in nutrients.
Wetlands	areas that, at least periodically, have waterlogged soils or are covered with a relatively shallow layer of water. Bogs, freshwater and saltwater marshes, and freshwater and saltwater swamps are examples of wetlands.
TOP All text by World Wildlife Fund © 2001