Worldwide Traffic, Impact, and the Evolutionary Trajectory of Invasive Populations in the Little Fire Ant Wasmannia auropunctata

EPA Grant Number: FP916398
Title: Worldwide Traffic, Impact, and the Evolutionary Trajectory of Invasive Populations in the Little Fire Ant Wasmannia auropunctata
Investigators: Mikhayev, Alexander S.
Institution: The University of Texas at Austin
EPA Project Officer: Packard, Benjamin H
Project Period: January 1, 2004 through December 31, 2004
Project Amount: $101,748
RFA: STAR Graduate Fellowships (2004) RFA Text |  Recipients Lists
Research Category: Academic Fellowships , Biology/Life Sciences , Fellowship - Entomology


The increase in worldwide human traffic has given rise to the scourge of nonnative species that displace natives and destabilize ecosystems. Ants are among the worst invaders—exotic ants have had catastrophic impacts on local faunas and floras, as well as negative effects on human health and agriculture. The objective of this research is tostudy the dynamics of spread, the evolutionary trajectory of long-term exotic species establishment, and the effects of community composition and environment on the impacts of invasion, using the invasive ant Wasmannia auropunctata as a model.


I will use molecular markers to map worldwide W. auropunctata traffic identifying the sources of each invasion. Using the resulting network, I will apply modern graph theory-based models of disease transmission to the spread of W. auropunctata by studying patterns of international maritime traffic. These models will allow the identification of probable locations of future infestations and the likelihood of an invasion to cause severe negative impacts. Additionally, using replicate invasions of different ages in a phylogenetic context, I will conduct behavioral experiments aiming to determine whether an exotic population evolves intraspecific aggression, a key parameter affecting the competitiveness of nonnative ant populations. Thus, I will be able to monitor the history of past invasions and to predict the outcome of future invasions.

At the very least, my work will provide a thorough description of the distribution, worldwide invasion dynamics, and some of the causes of underlying competitive exclusion of other species by the highly destructive ant W. auropunctata. I hope that my work will be more general, applying not just to this particular species, but also to other species of ants. Overall, my work will not only provide a framework for monitoring and combating the future spread of W. auropunctata but will also address general issues of exotic species biology applicable to a wide variety of invaders.

The completion of this project will help curtail the irreparable damage to biodiversity caused by the increase in world commerce and travel. Tropical islands, such as those invaded by W. auropunctata, provide an effective early warning system for the impacts of invasive species. As mainland habitat is fragmented and degraded, it acquires many of the properties of island ecosystems, including limited habitat area and missing functional groups. Thus, a better understanding of invasions in island ecosystems may improve our ability to protect both the islands and mainland habitat fragments.

Supplemental Keywords:

fellowship, invasives, nonnative species, ecosystem dynamics, Wasmannia auropunctata, fire ants, ants, disease transmission models, environmental impacts, ant population competitiveness,, Scientific Discipline, Ecosystem Protection/Environmental Exposure & Risk, Entomology, Habitat, Ecology and Ecosystems, plant insect interactions, community composition, invasive insect species, genetic consequences, ecological consequences, habitat fragmentation, traffic effect

Relevant Websites:

2004 STAR Graduate Fellowship Conference Poster (PDF, 1p., 130KB, about PDF)

Progress and Final Reports:

  • Final