Chapter 53 Flashcards
community
an interacting group of various species in a common location.
host
an organism that harbors a parasitic, a mutual, or a commensal symbiont, typically providing nourishment and shelter.
disturbance regime
a temporary change in environmental conditions that causes a pronounced change in an ecosystem. Disturbances often act quickly and with great effect, to alter the physical structure or arrangement of biotic and abiotic elements.
competition
n interaction between organisms or species in which both the organisms or species are harmed. Limited supply of at least one resource (such as food, water, and territory) used by both can be a factor.
predation
A form of symbiotic relationship between two organisms of unlike species in which one of them acts as predator that captures and feeds on the other organism that serves as the prey.
primary succession
occurs in essentially lifeless areas—regions in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier.
coevolutionary arms race
a struggle between competing sets of co-evolving genes, traits, or species, that develop adaptations and counter-adaptations against each other
predator
an organism which feeds on prey.
secondary succession
a process started by an event (e.g. forest fire, harvesting, hurricane) that reduces an already established ecosystem (e.g. a forest or a wheat field) to a smaller population of species, and as such secondary succession occurs on preexisting soil
commensalisms
a relationship between individuals of two species in which one species obtains food or other benefits from the other without either harming or benefiting the latter.
prey
an organism which gets fed on by predators.
intraspecific competition
an interaction in population ecology, whereby members of the same species compete for limited resources. This leads to a reduction in fitness for both individuals.
standing/constitutive
The total amount or weight, or energy content, of (a portion of) organisms existing in a specific area at a particular time.
pioneering species
are hardy species which are the first to colonize previously disrupted or damaged ecosystems, beginning a chain of ecological succession that ultimately leads to a more biodiverse steady-state ecosystem.
interspecific competition
a form of competition in which individuals of different species compete for the same resources in an ecosystem (e.g. food or living space). … If the resource cannot support both populations, then lowered fecundity, growth, or survival may result in at least one species.
defenses
anatomical mechanisms that protect prey from predators.
weed
Any plant that is growing in a place where a human wants a different kind of plant or no plants at all.
niche differentiation
refers to the process by which competing species use the environment differently in a way that helps them to coexist.
consumption
The using up of something, especially the rate at which it is used.
high-productivity
refers to the rate of generation of biomass in an ecosystem. It is usually expressed in units of mass per unit surface (or volume) per unit time. high productivity means that there is a high generation of biomass in the ecosystem.
character displacement
the phenomenon where differences among similar species whose distributions overlap geographically are accentuated in regions where the species co-occur, but are minimized or lost where the species’ distributions do not overlap.
niche
the particular set of habitat requirements of a certain species and the role that species has in its ecosystem
mimicry
a phenomenon in which one species has evolved to look or sound like another species
facilitation
early arriving species make the conditions more favorable for later species
competitive exclusion principle
two species cannot coexist in the same ecological niche
mullerian mimicry
type of mimicry where two harmful species mimic each other
tolerance
early arriving species do not affect the conditions for later species
batesian mimicry
type of mimicry where one harmless species mimics a harmful one
inhibition
early living species negatively affect the conditions for later species
asymmetric competition
one species suffers a greater fitness decline than the other
inducible defenses
defenses that appear only in the presence of a predator
symmetric competition
both species in competition suffer the same amount of fitness decline
meta analysis
a compilation of several previous studies
species richness
number of species present in an ecological community
fundamental niche
space that a species occupies in the absence of a competitor
top down control hypothesis
population size is limited by predators or herbivores
species diversity
variety and relative abundance of species present in an community
realized niche
niche species occupies in the presence of a competitor
climax community
the stable final community that develops from ecological succession
intermediate disturbance
moderate ecological disturbance is associated with higher species diversity than either low or high disturbance
herbivory
practice of eating plants
energy hypothesis
high temperatures increase species diversity by increasing productivity and the likelihood that organisms can tolerate the physical conditions in a region
keystone species
species that has a greater impact on its ecosystem than its numbers would indicate
disturbance
any event that disrupts a community, usually causing loss of some individuals or biomass
shannon index
used to characterize diversity within a species
