33. Macroecology Flashcards
Habitat fragmentation
the division of previously intact habitat into isolated patches, typically due to human activity
Corridors
some sort of strip of habitat connecting similar habitat- types patches across a landscape, help mitigate the effects of fragmentation
Biogeography
attempts to document and understand spatial patterns of biodiversity at a large spatial scale
ecological niche modeling
attempt to predict species ranges including expansion and retractions based on info about a species current distribution and niche requirements combined with spacial data
what are some limitations of ecological niche modelling
focuses on realized niches, doesnt consider fundamental niches
very hard to model rare species bc we have fewer observations of them to gather data from
island
any portion of isolated habitat
how is species richness related to island size
richness increases with island size (likely to have more resources< can support larger populations, greater niche diversity)
richness decreases with island isolation
equilibrium model of island biogeography
MacArthur & Wilson
species richness on islands modelled as a dynamic balance between immigration and extinction of species
Rate of immigration v extinction
rate of arrival of new species on an island
v
rate at which species go extinct on an island
immigration rates are highest on new islands, extinction rates are highest at high densities of species on an island
WHat are immigration and extinction mainly influenced by
isolation
v
area
species turnover
change in species composition
what latitudes are species richness highest at
closer to the equator in the tropics
why are the tropics more diverse
less disturbance
greater land and water area
uniform temperatures
