Thus, the biodiversity found on an island is a function of (1) how close the island is to the mainland, and (2) how large the island is. As you might imagine, larger islands tend to have more species than smaller islands because there is greater habitat diversity and, therefore, more resources available.
How does the size and distance from the mainland affect the biodiversity of an island?
The two factors that determine the species diversity found in isolated ecosystem such as an island is its size and distance from the nearest mainland. This is the theory of island biogregrophy. Size affects an island’s biodiversity because there are less niches, less habitats, and lower immigration.
How does distance affect island biogeography?
Immigration and emigration are affected by the distance of an island from a source of colonists (distance effect). Usually this source is the mainland, but it can also be other islands. Islands that are more isolated are less likely to receive immigrants than islands that are less isolated.
How does distance from the mainland affect the immigration and extinction rates of species on an island?
Islands far from the mainland are species-poor regardless of area because immigration is so difficult. However, as island area increases, the extinction rate decreases, so species richness increases rapidly in comparison to near islands.
What is the relationship between the size of the island and distance extinction rate?
Larger islands have more space than smaller islands, so there are likely to be more resources available for species to use. The opposite is true for smaller islands. Therefore extinction rates are larger on small islands.
How does distance from the mainland impact biodiversity?
Area increases diversity because a larger plot is likely to have more habitats, hence niches, to support a greater variety of species. How does the distance from the mainland affect the number of species? The farther from the mainland you go, the less species richness.
What is the relationship between colonization and distance from the mainland?
The farther an island is from the mainland, the fewer the number of species found on the island. Why is a new island more hospitable to colonizers than an older island is? The intensity of both competition and predation is less on the newer island.
How does an islands size and distance from the mainland affect the islands species richness?
Thus, species richness is expected to decrease in smaller islands farther from the mainland due to greater local extinctions and less immigration, and to increase in larger islands closer to the mainland because of the high levels of immigration and larger area available for foraging (MacArthur & Wilson, 1963, 1967; …
What happens to diversity the farther an island is to a continent?
Basically, The farther away the island, the less diverse it will be. There are lower immigration rate (organisms leaving). This is the “distance effect”
What factors affect island biogeography?
Island biogeography is determined by three processes: immigration, evolution, and extinction. These processes are determined by the area and isolation of islands such that smaller and more isolated islands have lower numbers of species than larger and less isolated islands.
How does the rate of immigration differ between islands close to the mainland and those far from the mainland?
For instance, everything else being equal, distant islands will have lower immigration rates than those close to a mainland, and equilibrium will occur with fewer species on distant islands. Close islands will have high immigration rates and support more species.
How does proximity to the mainland affect the immigration rate on the island Why?
Generally, as the number of species present increases, the immigration rate decreases and the extinction rate increases. … 1) Immigration is higher on near islands than on distant islands (in relation to the mainland), hence the equilibrium number of species present will be greater on near islands.
What are the two main factors that affect immigration and extinction on an island?
The Equilibrium Model of Island Biogeography (EMIB) states that, other things being equal, area and geographic isolation are the two main factors determining extinction and immigration rates, which in turn regulate the level of species richness that is reached at a dynamic equilibrium , .
How does a habitat fragment’s size and distance of a source habitat affect its biodiversity?
Habitat fragmentation decreases the size and increases plant populations’ spatial isolation. With genetic variation and increased methods of inter-population genetic divergence due to increased effects of random genetic drift, elevating inbreeding and reducing gene flow within plant species.
Which islands were most likely to see the greatest number of species smaller islands or larger islands islands closer to the mainland or farther from the mainland?
What kind of island is likely to have the highest number of species? The equilibrium theory of island biogeography predicts that large islands close to the mainland will have more species than small islands that are distant from the mainland.
What is the equilibrium theory of island biogeography?
The equilibrium theory of island biogeography creates a general framework in which the study of taxon distribution and broad island trends may be conducted. Critical components of the equilibrium theory include the species-area relationship, island-mainland relationship, dispersal mechanisms, and species turnover.