Chapter 4 - Species Interactions and Community Ecology Flashcards
phytoplankton
microscopic photosynthetic algae, pratists, and cyanobacteria that drift near the surface of water bodies and generally form the first trophic level in an aquatic food chain.
zooplankton
tiny aquatic animals that feed on phytoplankton and generally make up the second layer of the food chain
competition
a relationship in which multiple organisms seek the same limited recourse
intraspecific competition
competition that takes place among members of the same species
interspecific competition
competition that takes place among members of two or more different species
fundamental niche
the full niche of a species
realized niche
the portion of the fundamental niche that is fully realized (used) by a species
species coexistence
an outcome of intraspecific competition in which no competing species fully excludes the other and the species continue to coexist
competition exclusion
an outcome of interspecific competition competition in which one species excludes another species from a resource entirely
character displacement
a phenomenon resulting from competition among species in which competing species evolve characteristics that better adapt them to specifically use the portion of the resource that they use. the species essentially become more different from each other reducing their competition
resource partitioning
the process by which species adapt to competition by evolving to use slightly different resources, or to use their shared resources in different ways, thus minimizing competition with one another
predation
the process in which one species (the predator) hunts, tracks, captures, and eventually kills its prey
predator
an organism that hunts, capture, kills and consumes individuals of another species, the prey
prey
an organism that is killed and consumed by another species
parasitism
a relationship in which one organism, the parasite, depends on another, the host, for nourishment or some other benefit while simultaneously doing the host harm
parasite
the organism in a parasitic relation ship that extracts nourishment or some other benefit from the host
host
the organism in a parasitic relationship that suffers harm while providing the parasite nourishment or some other benefit
parasitoid
an insect that parasitizes other insects, generally causing eventual death of the host
pathogens
a parasite that causes disease in its host
coevolution
the process in which two or more species evolve in response to each other. parasites and hosts may coevolve , as may flowering plants and their pollinators
herbivores
animals that only consume plants
pollination
a plant-animal interaction in which one organism (for example a bee or hummingbird) transfers pollen (containing male sex cells) from flower to flower, fertilizing ovaries that grow into fruits with seeds
trophic levels
ranking in the feeding hierarchy of a food chain. organisms that have higher trophic levels consume those at lower trophic levels
mutualism
a relationship in which all participating organisms benefit from their interactions
symbiosis
a relationship between different species of organisms that live in close physical proximities. people most often use this term to reference mutualistic relationships, but it can be used for both parasitic and mutualistic relationships
tertiary consumer
an organism that consumes secondary consumers and feeds at the fourth trophic level
carnivore
an organism that consumes animals
decomposer
an organism such as a fungus or bacterium, that breaks down leaf litter and other non-living matter into simple constituents that can be taken up and used by plants
food chain
a linear series of feeding relationships as organisms feed on one another, energy is transferred from lower to higher trophic levels
food web
a visual representation of feeding interactions within an ecological community that shows an array of relationships between organisms of different trophic levels
keystone species
a species that has an especially far reaching effect on a community
trophic cascade
a series of changes in the population sizes of organisms at different trophic levels in a food chain, alluring when predators at higher trophic levels indirectly promote populations of organisms at low trophic levels in check. trophic cascades may be evident when a top predator is eliminated from a system
disturbance
an event that affects environmental conditions rapidly and drastically, resulting in changes to the community and ecosystem. disturbance can be natural, or it van be caused by humans
succession
a stereotypical series of changes in the structure of an ecological community through time
primary succession
a stereotypical series of changes as an ecological community develops overtime, beginning with a lifeless substrate in terrestrial systems, primary succession begins when a piece of rock, sand, or sediment becomes newly exposed to the atmosphere and pioneer species arrive. when soil is lost
secondary succession
a stereotypical series of changes as an ecological community develops overtime, beginning when some event disrupts or dramatically alters an existing community
resistance
the ability of an ecological community to remain stable in the presence of a disturbance
resilience
the ability of an ecological community to change in response to disturbance but later return to its original state.
pioneer species
a species that arrives earliest, beginning the ecological process of succession in a terrestrial of aquatic community
phase shift (regime shift)
a fundamental shift in the overall character of an ecological community generally occurring after some extreme disturbance and after which the community may not return to its original state
no-analog community (novel community)
an ecological community composed of a novel mixture of organisms, with no current analog or historical precedent
introduced species
species introduced by humans from one place to another (whether intentionally or not), a minority of introduced species become invasive species
invasive species
a species that spreads widely and rapidly becomes dominant in a community, interfering with the communities normal functions
climax community
in the traditional view of ecological succession, a community that remains in place with little modification (until a disturbance comes along)
restoration ecology
the study of the historical conditions of ecological communities as they existed before humans altered them. principles of restoration ecology are applied to the practice of ecological restoration
ecological restoration
efforts to reverse the effects of human disruption of ecological systems and to restore communities to their conditions before disruption
biome
a major regional complex of similar plant communities; a large ecological unit defined by its dominant plant type and vegetation structure
species diversity
the number of organisms and their corresponding populations in an area
species richness
variety is the spice of life, it makes you rich (species variety)
species evenness
the numbers of organisms of each species that are present (and if they are similar)
