What equation do we use to find a number of species diversity indices? Correct Ans-
Shannon Index
Shannon Index Equation Correct Ans-H= the Shannon index value
Pi= the proportion of individuals found in the -ith species
Ln= natural log
s= number of species in the community.
Species Composition Correct Ans-the identity of the species present in the community.
Trophic Cascade Correct Ans-When the rate of consumption at one trophic level results in
a change in species abundance or composition at lower trophic levels.
Example: When sea otters consume urchins which allows for the kelp forests to grow.
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Trophic Facilitation Correct Ans-Occurs when a consumer is indirectly helped by a positive
interaction between its prey and another species.
Example: When Juncus was removed, Iva growth rate decreased. But when Iva was removed,
Junca was not affected.
Foundation Species Correct Ans-The total affect of the species is proportionate to the size
and abundance of the species.
Example: Trees are big and abundant, their affect is also great.
Song birds are small and less abundant, they have little affect on the environment.
Keystone species Correct Ans-Their total affect as a species in not to their abundance.
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Example: Pisasters, sea otters
Communities Correct Ans-Groups of interacting species that occur together at the same
place and time.
Functional group Correct Ans-A subset of a community that includes species that function
in similar ways but may or may not use similar resources.
Food web Correct Ans-a representation of the trophic or energetic connections among
species within a community.
Trophic Levels Correct Ans-groups of species that have similar ways of interacting and
obtaining energy.
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Horizontal Interactions Correct Ans-non-trophic interactions, such as competition and
positive interactions.
Species Diversity Correct Ans-a measure that combines species richness (number of
species) and their abundances compared with those of the other species (species evenness).
Species richness Correct Ans-Easiest metric to determine; simply counts all the species in
the community.
Species Evenness Correct Ans-Tells us the commonness or rarity of species; need to know
abundance of each species in a community.
Ecosystem Engineers Correct Ans-Species that are able to create, modify, or maintain
physical habitats for themselves and other species.