The Nature of Communities Flashcards
how are invasive species problematic
they compete with the native species
How does one very abundant invasive species influence the other species in the community?
communities (def.)
groups oof interacting species that occur together at the same place in time
Community (def).
A number of species in a single space
What might a physically defined community include?
All species in a sand dune, mountain stream, or desert.
What may a Biologically defined community include?
all the species associated with a kelp forest, freshwater bog, or a coral reef
Taxonomic affinity
all of a certain animal within a community
Functional group
species that function in similar ways
trophic level
describe the feeding positions of organisms in ecosystems
How can organisms be grouped?
into trophic levels
1st trophic level
autotrophs
What is another name for auotroph?
producers
second trophic level
herbivores that consume autotrophs, also include detritivores that consume dead organic matter
3rd trophic levels
Carnivores that consume animals from the level below
dead organisms and feces are consumed by organisms called
detritivores
Decomposition
the breakdown of nutrients in decaying matter.
Species diversity
combines species richness and species evenness
Species richness
the number of species in a community
Species evenness
relative abundance compared with one another
Species accumulation curve
species richness plotted as a function of total number of individuals counted
Direct interaction
between two species
Indirect interactions
The relationship between two species is mediated by a third (or more) species.
trophic cascade
carnivore eats an herbivore (a direct negative effect on the herbivore)
trophic facilitation
A consumer is indirectly facilitated by a positive interaction between its prey and another species.
another name for dominant species
foundation species
keystone species
a species that has strong effects because of their role in a community
