29- local patterns of diversity Flashcards
what does an ecological community include?
all species that occupy the same habitat at the same time
what does an ecosystem include?
living organisms, abiotic components and the interactions between them
what three filters determine which species will occur in a community?
dispersal filter
environmental (abiotic) filter
species interaction (biotic) filter
what is dispersal filter
some of these species will disperse to a certain area
what is an environmental (abiotic) filter
some of the species that disperse there will be able to germinate and grow there
what is a species interaction (biotic) filter?
some of those species will be able to survive interaction with the other species present there
why doesn’t speciation determine local species diversity?
while speciation differs between biomes, it doesn’t differ at the local scale (between communities)
how do species coexist in a community?
they occupy different niches, i.e. they use different resources and play different roles = resource partitioning AKA niche differentiation
what is a fundamental niche?
the space and resources it uses when it doesn’t interact with any other species, i.e. it’s maximum range
what is the realized niche of a species?
the realized niche of a species is the space and resources it uses when competitors, predators, parasites are around
ex. two finch species live separately on different islands they eat certain seeds. when they coexist on the same island, their realized niches shift so that there is less competition
what is competitive exclusion principle
if the niches of two species are too similar and overlap too much they are not likely to coexist
what is predator mediated coexistance?
when a predator population is high, none of the prey populations can grow large enough to outcompete the othe
keystone species
look it up idiot
