Patterns in Nature

What occurs where (and why) and why do some places harbor more species than others are basic questions for ecologists.  Some species simply live in different places: fish live underwater, birds do not. Adaptations follow: most fish have gills; birds have lungs. “A fish out of water” is the expression for a person — and an animal — in the wrong place.  But not all patterns are trivial. Travel along any gradient — up a mountain, from forest into desert, from a north-facing slope to a south-facing slope, from low tide to high tide on a shoreline, from Arctic tundra to tropical rain forest — and the species change. What explains the patterns of these distributions? Some patterns might be as random as a coin toss.  But as with a coin toss, can ecologists differentiate associations caused by a multiplicity of complex, idiosyncratic factors from those structured by some unidentified, but simple mechanisms? Can simple mechanisms that structure communities be inferred from observations of which species associations naturally occur? 

This book is about the identification and interpretation of nature’s large-scale patterns of species co-occurrence and what we can deduce from them about how nature works.  It draws upon a critical debate between Jared Diamond and Dan Simberloff, one which resonates today as the dynamics of species occurrence are shifting rapidly in a changing global environment.