Final answer:
Island biogeography, shaped by factors such as migration, speciation, and extinction rates, is influenced by an island's size, distance from the mainland, and geographic diversity, affecting species richness and conservation strategies.
Step-by-step explanation:
Six Basic Factors of Island Biogeography
The concept of island biogeography is foundational in understanding the diversity and distribution of species on islands. The work of Robert H. MacArthur and Edward O. Wilson published in 1967 provides insights into the dynamics affecting biodiversity. Here are six critical factors that lead to island biogeography:
- The distance of an island from the mainland influences migration rates; remote islands typically have lower migration rates and, consequently, a lower equilibrium number of species.
- Islands closer to the mainland may have higher species numbers due to easier access for migration.
- Small islands, due to their size, tend to have lower immigration rates since they are harder to find and have less geographic diversity, which means fewer available niches for speciation.
- Island biogeography also predicts that smaller islands support smaller populations, increasing the likelihood of extinction.
- Evidence suggests that the number of species on an island gradually aligns with the diversity found on the originating mainland over time, assuming migration is possible.
- The theory has been applied to habitat fragments in landscapes, often treated as "islands" of biodiversity.
These principles have profound implications for the design of biological preserves, the conservation of biodiversity, and the understanding of evolutionary processes.