The island biogeography model of Robert MacArthur and E.O. Wilson predicts a higher value of ?, the equilibrium number of species, for larger islands close to a source pool and a lower value of ? for small islands far from the source pool. Their reasoning for these predictions is that larger islands support larger populations, lowering the risk of extinction, while closer islands have higher immigration rates because the immigrants do not have to travel as far. What other reasons could you give to justify their predictions? Check all that apply.

Question

_____ Larger islands tend to support species that are more adaptable and therefore, less prone to extinction.
_____ Larger islands tend to have a more varied physical environment, creating more ecological niches.
_____ Closer islands are more likely to have intermediate levels of disturbance, increasing diversity.
_____ Larger islands act as larger "targets" for colonization; immigrants are more likely to land on a larger island than a smaller one
_____ Closer islands are more likely to receive immigrants of species already present on the island, and this continued immigration can rescue species that might have otherwise gone extinct.

Answer 1

_____ Larger islands tend to support species that are more adaptable and therefore, less prone to extinction.
__X__ Larger islands tend to have a more varied physical environment, creating more ecological niches.
_____ Closer islands are more likely to have intermediate levels of disturbance, increasing diversity.
__X__ Larger islands act as larger "targets" for colonization; immigrants are more likely to land on a larger island than a smaller one
__X__ Closer islands are more likely to receive immigrants of species already present on the island, and this continued immigration can rescue species that might have otherwise gone extinct.