Abstract
BackgroundThe dispersal ability of queens is central to understanding ant life-history evolution, and plays a fundamental role in ant population and community dynamics, the maintenance of genetic diversity, and the spread of invasive ants. In tropical ecosystems, species from over 40 genera of ants establish colonies in the stems, hollow thorns, or leaf pouches of specialized plants. However, little is known about the relative dispersal ability of queens competing for access to the same host plants.Methodology/Principal FindingsWe used empirical data and inverse modeling—a technique developed by plant ecologists to model seed dispersal—to quantify and compare the dispersal kernels of queens from three Amazonian ant species that compete for access to host-plants. We found that the modal colonization distance of queens varied 8-fold, with the generalist ant species (Crematogaster laevis) having a greater modal distance than two specialists (Pheidole minutula, Azteca sp.) that use the same host-plants. However, our results also suggest that queens of Azteca sp. have maximal distances that are four-sixteen times greater than those of its competitors.Conclusions/SignificanceWe found large differences between ant species in both the modal and maximal distance ant queens disperse to find vacant seedlings used to found new colonies. These differences could result from interspecific differences in queen body size, and hence wing musculature, or because queens differ in their ability to identify potential host plants while in flight. Our results provide support for one of the necessary conditions underlying several of the hypothesized mechanisms promoting coexistence in tropical plant-ants. They also suggest that for some ant species limited dispersal capability could pose a significant barrier to the rescue of populations in isolated forest fragments. Finally, we demonstrate that inverse models parameterized with field data are an excellent means of quantifying the dispersal of ant queens.
Highlights
The approximately 14,000 species of ants account for roughly one-third of the world’s insect biomass [1]
The dispersal ability of foundress queens is central to understanding ant life-history evolution, and plays a fundamental role in ant population and community dynamics, the maintenance of genetic diversity, and the spread of invasive ant species [2,3,4,5]
The median distance from colonized seedlings to the nearest potentially reproductive colony was significantly different among ant species (Kruskal-Wallis, H = 13.96, df = 2, p,0.001, Figure 3); experimentally transplanted vacant seedlings colonized by Crematogatser laevis queens were significantly further from reproductive colonies than those trap plants colonized by queens of either Azteca sp. or Pheidole minutula (Steele’s Nonparametric Multiple Comparison Test [27], Table 1)
Summary
The approximately 14,000 species of ants (family Formicidae) account for roughly one-third of the world’s insect biomass [1]. The dispersal ability of foundress queens is central to understanding ant life-history evolution, and plays a fundamental role in ant population and community dynamics, the maintenance of genetic diversity, and the spread of invasive ant species [2,3,4,5]. Theory suggests that interspecific differences in the dispersal capability of ant queens play a key role in the maintenance of diversity in these communities, either via tradeoffs between dispersal ability and other life-history traits (e.g., competitive ability, colony fecundity), or from the interaction of dispersal limitation with spatial heterogeneity in host-plant density (reviewed in [3]). The dispersal ability of queens is central to understanding ant life-history evolution, and plays a fundamental role in ant population and community dynamics, the maintenance of genetic diversity, and the spread of invasive ants. Little is known about the relative dispersal ability of queens competing for access to the same host plants
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
