lec 19 Flashcards
The rate of species extinction will _____
increase as the number of speies occupying the island increases
Later immigrants may be unable to establish populations because
earlier immigrants already occupy available habitats and resources
If the number of species living on the island exceeds S,
so then ___________ will decline
the extinction rate is greater than the immigration rate
- species richness
If the number of species living on the island is lower than S
the immigration rate is greater than the extinction rate
- species richess will increase
Island Biogeography] Equilibrium is affected
the size of the island and the distance of the island from the mainland
the greater the distance to an island
the less likely species will be able to immigrate
Island Biogeogrpahy
If the islands are the same distance from the mainland
S will be greater for the island with the largest area
- on larger island extinction rates are lower
- larger islands generally have more habitats and resources
metapopulation theory: ________
For a particular species, the landscape is _______
- examines the colonization and local extinction of local population of a single species in an array of patches on a broader landscape
- patches of potential habitats, that vary in size, quality, degree of isolation from eachother
each metapopulation patch can potentially
This local population is connected
support a distinct, partially isolated subpopulation
is connected to other patches by varying degrees through dispersal of individuals
Metapopulation dynamics involve
two set of processes operating at two distinct spatial scales: single patch, landscape
single patch
individuals move and interact with each other during routine actiities
landscape
local populations interact through dispersal and colonization
colonization
is the movement of individuals from occupied patches to unoccupied patches
dispersing individuals may have a
significant chance of failing to locate another suitable patch to colonize
metacommunity
a set of local communities inhabiting discrete patches that are linked by dispersal
changing mosaic factors
disturbances
succesional changes
island biogeogrraphy, metapopulations and metacommunites and the ruels that guide them
Disturbances
alter the biological and physical structures of these communites (Mosaics)
Successional changes
occur within these communities
island biogeography
the study of colonization and survival in island communites
Examples of an island
A piece of land surrounded by water An oasis in the desert a woodlot in the center of a farm field A park in a city A wetland surrounded by farmland
The study of island biogeography combines
_______ - __________
and
_______ - ___________
Connectivity - how is the island connected to the source population
Patch size - how big is the island
The theory of island biogeography was developed to
explain patterns of species richness on islands
For an uninhabited island _______
The species with the greatest dispersal ability
- the mainland species are the pool of possible colonizing species
- will be the first to colonize
Immigration rate declines with increasing #’s of species on islands because
- when all mainland species are found on the island, the immigration rate is 0
- successful establishment of a new species on an island is based on whether a niche has been filled yet
Adaptive radiation
The process whereby a single ancestral species evolves into a wide array of descendants
metapopulation persistence results in
recolonization, because all local populations can potentially go extinct
