communities 2

species pool

number of species after speciation and before extinction

populations, assembly rules, and resources

create the permitted species combinations

assembly rules

colonization probability, habitat requirements, competitive interactions (things that say what can live in this area, high likely it is to live in the area)

populations

dispersal ability, competitive ability, exploitation strategy (ability to spread in the area)

community

number is impacted by stable coexistence and partitioning of resources

resources

predictability, productbility, variety (go into what species are permitted in the area)

margin and center

birds have a common core where they will be most found that has th4e right conditions for them (center), rare along the edges of the region (margin),

source and sink population

oak is better habitat and find more birds there (source) sink is overflow populations and is not a sustaining population (sink)

generalist and specialist

instrinsic characteristic, why do we have species that are rare everywhere, evolutionary success in being rare

variable environment

varying environment will cause some to boom and other times to be a rarer species

seasonality

period of years of different dominant species

delayed density dependence

lead to cycles in commonness and rarity

immigration and extinction

island biogeography, local extinction on island with small populations, can see turnover and fluctuation of species numbers

diversity scales with area

as area increases the number of species linearly increases

equilibrium theory

number of species on island is an equilibrium between immigration and extinction rate, curved model due to competition (increase number less immigration) (too many species, more that leave)

additional factors to the equilibrium theory

immigration rate, extinction rate, close or distant to mainland, small or large islands (large islands have low extinction rate) (more immigration if close to mainland) will shift equilibrium

issue with equilibrium theory

doesn’t show dynmics of island

things that vary with island size (and is against equilibrium theory)

number of different habitats (number of habitats decreases or increases where or how many can life)

species diversity varies by latittude

increases as close to equator,

Janzen and top of mountains

mountains have high diversity of species because of the varying temperature regions they have (gets colder as you go up) more time to develop niches

greater range of niches

tropics have had more time to make more habitats, have a greater range of fruits

Mauro and Braxil

large bill birds take large speeds and disperse them, trees need this, will develop smaller bird seeds as larger birds decrease (due to urbanization and hunting)