Correct option is D
The theory of island biogeography, proposed by Robert MacArthur and Edward O. Wilson in 1967, primarily focuses on the concepts of immigration, competition, and equilibrium. These concepts explain the diversity and distribution of species on islands, which can be used as a model for understanding ecological dynamics in isolated environments. The theory suggests that the number of species on an island is determined by the balance between immigration (the arrival of new species) and extinction (the loss of species). The equilibrium model suggests that an island reaches a balance or equilibrium point where the rate of immigration equals the rate of extinction. Competition between species also plays a critical role in shaping species composition.
However, speciation (the process of the formation of new and distinct species) is not directly addressed in the island biogeography theory, even though speciation can occur as a result of isolation. The theory focuses more on species turnover (immigration and extinction rates) rather than on the mechanisms by which new species arise.
Information Booster:
Immigration: The process by which species move to a new area, such as an island. In island biogeography, higher rates of immigration lead to more species arriving on an island, contributing to its biodiversity.
Competition: The interaction between species in which they compete for limited resources (such as food or space). Increased competition on islands typically leads to the exclusion of less competitive species and affects species composition.
Equilibrium: The idea that an island reaches a dynamic equilibrium, where the rate of new species immigration equals the rate of species extinction. This balance determines the number of species that can be supported on the island at any given time.
Additional Information:
Option (a) - Competition: This concept is crucial in the island biogeography theory. The theory acknowledges that competition affects the number of species on an island by influencing which species can coexist and persist.
Option (b) - Immigration: Immigration is a fundamental concept in island biogeography. It refers to the arrival of new species to the island and contributes to the total species count, which is influenced by the island's distance from the mainland and its size.
Option (c) - Equilibrium: The equilibrium theory is central to island biogeography, suggesting that the number of species on an island is determined by the balance between immigration and extinction, influenced by the size and isolation of the island.
