Relationship between the ratio of 1850 (± 20) and current inflection points extracted from logistic models by archipelago and latitude. On the top left are the equation and variation explained. Archipelagos are the Channel Islands (CHA), West Iceland (ICE), West Ireland (IRE), Quarnero/Kvarner (QUA), Macaronesia (MAC), Maddalena (MAD) and Shetland. The total (TOT) incorporates all 234 islands.