Island biogeography theory underpins how scientists design nature reserves

MacArthur and Wilson linked island size and isolation to immigration and extinction rates — predicting richer biotas on larger, nearer islands. Conservationists later treated habitat fragments as islands in a sea of human land use.

The framework favors bigger reserves, closer spacing, and connecting corridors when possible, while acknowledging that real landscapes are messier than oceanic models. It remains a starting map for reserve geometry.

Ecology borrowed an archipelago to save continents. Island biogeography turned distance and area into rules of thumb for keeping species alive on a fragmented Earth.