LAUSR

The accumulation of species through time has been proposed to have a hump‐shaped relationship on volcanic islands (highest species richness during intermediate stages of an island's lifespan). Change in topographic complexity (TC) of islands over time is assumed to follow the same relationship. However, TC can be measured in different ways and may not have the same impact across taxonomic groups. Here, we quantify TC across the Galápagos Islands and test the assumption that TC follows a predictable trajectory with island age. Subsequently, we ask whether including TC improves statistical models seeking to explain variation in species richness across islands.