The Principle of Island Biogeography — Passage and Quiz

The Principle of Island Biogeography explains how the size and distance of islands affect the number of species that can live there. Proposed by ecologists Robert MacArthur and E.O. Wilson in the 1960s, this principle applies not only to islands but also to isolated habitats like mountain tops or forest fragments.

The principle has two main components:

1. Island Size: Larger islands tend to have more species than smaller ones. This is because larger islands offer more resources, habitats, and space for species to thrive.

2. Distance from Mainland: Islands closer to the mainland have more species than those farther away. This is because species can more easily migrate to nearby islands.

    

The principle also explains how extinction and colonization rates affect biodiversity. On small, distant islands, extinction rates are higher because resources are limited, and colonization rates are lower because fewer species can reach the island.

Island biogeography has important implications for conservation. For example, protecting large, connected habitats can help maintain biodiversity. It also highlights the challenges of preserving species in small, isolated reserves.

Fun fact: The Principle of Island Biogeography was first tested on islands in the Florida Keys, where researchers studied the distribution of insects and birds.