Patterns of spread in biological invasions dominated by long-distance jump dispersal: Insights from Argentine ants

Abstract

Invading organisms may spread through local movements (giving rise to a diffusion-like process) and by long-distance jumps, which are often human-mediated. The local spread of invading organisms has been fit with varying success to models that couple local population growth with diffusive spread, but to date no quantitative estimates exist for the relative importance of local dispersal relative to humanmediated long-distance jumps. Using a combination of literature review, museum records, and personal surveys, we reconstruct the invasion history of the Argentine ant (Linepithema humile), a widespread invasive species, at three spatial scales. Although the inherent dispersal abilities of Argentine ants are limited, in the last century, human-mediated dispersal has resulted in the establishment of this species on six continents and on many oceanic islands. Humanmediated jump dispersal has also been the primary mode of spread at a continental scale within the United States. The spread of the Argentine ant involves two discrete modes. Maximum distances spread by colonies undergoing budding reproduction averaged 150 m͞year, whereas annual jump-dispersal distances averaged three orders of magnitude higher. Invasions that involve multiple dispersal processes, such as those documented here, are undoubtedly common. Detailed data on invasion dynamics are necessary to improve the predictive power of future modeling efforts.stratified diffusion ͉ invasive ants ͉ Linepithema humile ͉ rate of invasion

Niemann–Pick type C2 protein mediating chemical communication in the worker ant

“…Our results provide insight into protein function and structure of NPC2 between vertebrates and ants in molecular evolution. Invasive ants such as the red imported fire ant, S. invicta, and the Argentine ant, Linepithema humile, cause environmental and economic impacts throughout the world (36,37). In Culex mosquitoes, a reverse chemical ecological approach using a carrier protein as a selective filter has been used to identify the minor components of oviposition attractant (38).…”

Spread of the invasive yellow-legged hornet Vespa velutina (Hymenoptera: Vespidae) in Italy

“…The spread of the yellow-legged hornet in Europe was characterized by a mix of a natural dispersal with a diffusion-like process (Suarez et al 2001;Villemant et al 2011a) and sudden jumps due to the passive transport of inseminated queens with commodities and vehicles (Marris et al 2011). Discriminating the effects of these two sources of dispersal is difficult, though it would be helpful for the establishment of an early warning system and to develop control plans.…”

Inferring introduction routes of invasive species using approximate Bayesian computation on microsatellite data

“…Two methods are traditionally used to make inferences about introduction routes: (1) Direct methods based on interception data and/or historical records of the presence or absence of the species (for example the study of Argentine ant by Suarez et al, 2001) and (2) indirect methods based on genetic relationships between populations (for example Kolbe et al, 2004;Ciosi et al, 2008). Such indirect methods are usually based on the calculation of genetic distance (for example Goldstein et al, 1999), assignment-likelihood statistics (Rannala and Mountain, 1997) and parsimony networks (for example Voisin et al, 2005).…”