title: Invasive plants have broader physiological niches.
abstract: Invasive species cost the global economy billions of dollars each year, but ecologists have struggled to predict the risk of an introduced species naturalizing and invading. Although carefully designed experiments are needed to fully elucidate what makes some species invasive, much can be learned from unintentional experiments involving the introduction of species beyond their native ranges. Here, we assess invasion risk by linking a physiologically based species distribution model with data on the invasive success of 749 Australian acacia and eucalypt tree species that have, over more than a century, been introduced around the world. The model correctly predicts 92% of occurrences observed outside of Australia from an independent dataset. We found that invasiveness is positively associated with the projection of physiological niche volume in geographic space, thereby illustrating that species tolerant of a broader range of environmental conditions are more likely to be invasive. Species achieve this broader tolerance in different ways, meaning that the traits that define invasive success are context-specific. Hence, our study reconciles studies that have failed to identify the traits that define invasive success with the urgent and pragmatic need to predict invasive success.
authors.affiliation: Department of Botany, University of Otago, Dunedin 9054, New Zealand; and steven.higgins@otago.ac.nz.
authors.forename: Steven I
authors.initials: SI
authors.lastname: Higgins
authors.affiliation: Centre for Invasion Biology and Department of Botany and Zoology, Stellenbosch University, Matieland 7602, South Africa.
authors.forename: David M
authors.initials: DM
authors.lastname: Richardson
mesh_terms: D000045:Acacia / Q000502:physiology*; D001315:Australia; D017753:Ecosystem; D005052:Eucalyptus / Q000502:physiology*; D058865:Introduced Species; D013045:Species Specificity
keywords: biological invasion; ecological niche; physiology; range size; tree invasions