APES Types of Species
ecological niche
each specie's distinct role played in the ecosystems where it is found; pattern of living
fossils
mineralized or petrified replicas of skeletons, bones, teeth, shells, leaves, and seeds, or impressions of such items found in rocks
reproductive isolation
mutation and change by natural selection operate independently in gene pools of geographically isolated populations. If the process continues long enough, members of the geographically and reproductively isolated populations may become so different in genetic makeup that they cannot produce live, fertile offspring if they are to be rejoined
species richness
number of different species a community contains
species diversity
number of different species a community contains combined with the relative abundance of individuals within each of those species
geographic isolation
occurs when different groups of the same population of a species become physically isolated from one another for long periods (physical barrier in way or when few individuals are carried to a new area by wind or flowing water)
species evenness
relative abundance of individuals within each of the species in a community
natural selection
second step in the process of biological evolution genes mutate, individuals are selected, and populations evolve that are better adapted to survive and reproduce under existing environmental condidtions
mass extinction
significant rise in extinction rates above the background level
endemic species
species that are found in only one area; especially vulnerable to extinction
keystone species
species that have a large effect on the types and abundances of other species in an ecosystem
generalist species
species that have broad niches; can live in many different places, eat a variety of foods, and often tolerate a wide range of environmental conditions
specialist species
species that have narrow niches; can live in only one type of habitat, use one or few types of food, and tolerate a narrow range of climatic and other environmental condition
nonnative species
species that migrate into or are deliberately or accidentally introduced into an ecosystem also called invasive, alien, or exotic species
foundation species
species that play a major role in shaping communities by creating and enhancing their habitats in ways that benefit other species
indicator species
species that provide early warnings of damage to a community or an ecosystem
eubacteria, archaebacteria, protists, plants, fungi, animals
the six specific groups of species
native species
those species that normally live and thrive in a particular ecosystem
extinction
when an entire species ceases to exist
background extinction
when species disappear at a low rate
speciation
when two species arise from one from natural selection for sexually reproducing species, a new species is formed when some members of a population have evolved to the point where they can no longer breed with other members to produce fertile offspring