Ch. 4 & 9 Flashcards
total way of life or role of a species in an ecosystem
(ecological) niche
species that migrates into an ecosystem or are deliberately or accidentally introduced into an ecosystem by humans
(nonnative) invasive species
any genetically controlled structural, physiological, or behavioral characteristic that helps an organism survive and reproduce under a given set of environmental conditions
adaptation
a speciation in which biological populations are physically and geographically isolated in some way (breeding only among themselves)
allopatric speciation
normal extinction of various species as a result of changes in local environmental conditions
background extinction (rate)
variety of different species, genetic variability among individuals within each species, variety of ecosystems and functions such as energy flow and matter cycling needed for the survival of species and biological communities
biodiversity
complete disappearance of a species from the earth (It happens when a species cannot adapt and successfully reproduce under new environmental conditions or when a species evolved into one or more species)
biological extinction
terrestrial regions inhabited by certain types of life, especially vegetation
biomes
the gradual movement of the continents across the earth’s surface through geological time
continental drift
wild species with so few individual survivors that the species could soon become extinct in all or most of its natural range
endangered species
species that is found in only one area and are especially vulnerable to extinction
endemic species
species with a broad ecological niche, they can live in many different places, eat a variety of foods, and tolerate a wide range of environmental conditions
generalist species
breakup of a habitat into smaller pieces, usually as a result of human activities
habitat fragmentation
acronym used by conservation biologists for the 6 most important secondary causes of premature extinction: Habitat destruction, degradation, and fragmentation; Invasive (nonnative species); Population growth; Pollution; Climate Change; and overexploitation
HIPPCO
species whose decline served as early warnings that a community or ecosystem is being degraded
indicator species
species that plays roles affecting many other organisms in an ecosystem
keystone species
catastrophic, widespread, often global event in which major groups of species are wiped out over a short time compared with normal (background) extinctions
mass extinction
species that normally live and thrive in a particular ecosystem
native species
process by which a particular beneficial gene or set of genes is reproduced in succeeding generations more than other genes
natural selection
when there is significant scientific uncertainty about potentially serious harm from chemicals or technologies, decision makers should act to prevent harm to humans and the environment
precautionary principle
species with a narrow ecological niche
specialist species
formation of two species from one species because of divergent natural selection in response to changes in environmental conditions; usually takes thousands of years
speciation
group of similar organisms and for sexually reproductive organisms, they are a set of individuals that can mate and produce fertile offspring
species
variety of species, measured by the number of different species contained in a community
species richness
the process through which new species evolve from a single ancestral species while inhabiting the same geographic region (potential mates aren’t in the same place at the same time)
sympatric speciation
wild species that is still abundant in its natural range but is likely to become endangered because of a decline in numbers
threatened species
change in the genetic makeup of a population of a species in successive generations (note: populations evolve, not individuals)
(biological) evolution
