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.
living predominantly or entirely in trees
a ring-shaped coral reef or string of coral islands, usually enclosing a shallow lagoon
the variety of life on Earth and the interconnections among living things
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.
refers to the living components of the environment (such as plants, animals, and fungi) that affect
pertaining to the north
slightly salty or briny. Brackish water is saltier than fresh water but less salty than seawater.
fishes, or any other animals, that are accidentally caught in fishing gear
a characteristic group of plants and animals living and interacting with one another in a specific region
under similar environmental conditions
the large-scale removal of trees from a habitat dominated by forest
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
Ecological or ecosystem services
valuable services provided by natural systems. Examples of ecological services include flood
control, air purification, and climate control.
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.
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.
a species threatened with extinction. The Florida panther and the California condor are endangered
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.
lasting for a very short time
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.
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.
the animals that live in a particular area
the plants that live in a particular area
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.
the science of space and place that brings together Earth’s physical and human dimensions in the
integrated study of people, places, and environments
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.
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.
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.
manure from animals like birds and bats
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.
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.
an organism that does not have a backbone
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,
pertaining to a mountainous region
a species that occurs naturally in an area or habitat. Also called indigenous species.
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.
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.
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.
the plant plankton and primary producers in aquatic ecosystems
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.
hunting, trapping, or fishing illegally
the area in which an organism may travel in its lifetime. Range also refers to the geographic
distribution of a particular species.
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.
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.
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).
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.
pertaining to the banks of a river or other body of fresh water
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
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
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.
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.
(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
meeting the needs of the present without diminishing the ability of people,
other species, or future
generations to survive.
a type of coniferous evergreen forest, found in the subarctic areas of North
America and Eurasia. Also
known as a boreal 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.
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
an upward flow of cold, heavy deep-sea water caused as offshore currents draw
surface water. The deep-sea water of upwellings is generally rich in nutrients.
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