Island Biogeography Flashcards
what is seen when we compare the z slope of mainland vs islands?
z slope is steeper in islands, slope gets steeper with increasing area
what is seen when looking at ant species in new guinea?
- same pattern of z slope, is steeper on islands
- small islands only have 10-20% of species with same area that mainlands have
smaller islands have ____ fewer species than the mainland
disproportionally
z slope is steeper for ______ than for ______
oceanic islands, areas of mainland
ecological disharmony
non-representative proportions of some species
island species have unusual forms due to lack of _____
predators
predators are usually absent on small islands due to higher extinction rate from….
small population size
ecological disharmony means that small islands have mostly species with _____ and lack _____
good dispersal, predators
extinction increases on small ____ and/or small ____
islands, population size
extinction on small islands leads to ____
species turnover
s hat represents the _____ in Macarthur and wilsons equilibrium model
equilibrium point
MacArthur and Wilson’s equilibrium model of island biogeography, success ____ as colonization _____, because available niches become filled. this leads to less _______ colonization
decreases, increases, successful
3 reasons small islands experience high extinction
small population size, resource depletion, inbreeding
essential feature of equilibrium theory 1:
number of species moves towards an equilibrium between extinction and colonization as a function of island area and distance
essential feature of equilibrium theory 2:
at equilibrium actual species composition is in continuous state of change as some species go extinct and new species colonize (high turnover of species as equilibrium is reached)
essential feature of equillibrium theory 3:
can predict numbers of species but not species composition
T/F: equilibrium theory can predict the numbers of species and species composition of an island based on island size and distance from shore
false - number of species but not species composition
s hat is ____ for large, near shore islands than for small, far shore islands
larger
rescue effect reduces _____
inbreeding
2 modifications to the equilibrium theory
target effect, rescue effect
what 2 process are encompassed by ‘biological possesses’ in the tripartite theory
immigration, extinction
what 2 features are encompassed by ‘island characteristics’ in the tripartite theory
area isolation (distance from mainland, other islands, etc)
