Biogeographic Regions: What Are They and What Can They Tell Us?

Post provided by Leonardo Dapporto, Gianni Ciolli, Roger L.H. Dennis, Richard Fox and Tim G. Shreeve

Every species in the world has a unique geographic distribution. But many species have similar ranges. There are many things that can cause two (or more) species to have similar ranges – for example shared evolutionary histories, physical obstacles (mountains, oceans etc.) or ecological barriers limiting their dispersal. As a consequence, different regions of the globe are inhabited by different sets of living organisms.

In the mid-19th century ecologists recognised that the earth could be divided into different biogeographic regions. Alfred Russel Wallace (1823–1913) played a key role in defining and recognising biogeographic regions. He improved the existing maps of  biogeographic regions and provided basic rules to identify them. His observation that some of these regions are home to similar species, despite being far away from each other and separated by significant barriers was the inspiration for Alfred Wegener’s theory of continental drift. In more recent years regionalisation has been used to understand the spatial drivers of biological evolution and to protect those regions characterised by particularly unique flora and fauna.

The biogeographic regions identified by Alfred Russel Wallace from The Geographical Distribution of Animals (1876)

The biogeographic regions identified by Alfred Russel Wallace from The Geographical Distribution of Animals (1876)

Despite the long history of biological regionalisation, the methods to identify biogeographic regions are still being improved. We are currently working in this exciting field of research and recently published ‘A new procedure for extrapolating turnover regionalization at mid-small spatial scales, tested on British butterflies’ in Methods in Ecology and Evolution. Continue reading