The Role of Ants in North American Grasslands
Ants are often considered important consumers and ecosystems engineers. As consumers, they can concentrate nutrients, and influence herbivore, decomposer, and predator communities. As ecosystem engineers, they can create, maintain, and modify habitat for other organisms. The collective effect of ants within an ecosystem can have important consequences to an ecosystem’s microbial, and plant communities (Wills and Landis 2018). Despite their dominance in terrestrial ecosystems, their importance and associated interactions have frequently been generalized from literature dedicated to ant species from subtropical and tropical regions. Therefore our understanding of their roles in temperate systems is relatively limited
To address gaps in our understanding of the role of ants in temperate systems my work explores two main areas.
Ants are often considered important consumers and ecosystems engineers. As consumers, they can concentrate nutrients, and influence herbivore, decomposer, and predator communities. As ecosystem engineers, they can create, maintain, and modify habitat for other organisms. The collective effect of ants within an ecosystem can have important consequences to an ecosystem’s microbial, and plant communities (Wills and Landis 2018). Despite their dominance in terrestrial ecosystems, their importance and associated interactions have frequently been generalized from literature dedicated to ant species from subtropical and tropical regions. Therefore our understanding of their roles in temperate systems is relatively limited
To address gaps in our understanding of the role of ants in temperate systems my work explores two main areas.
- Examining how land-use history, management history, soil quality, and plant diversity impact ants and other beneficial ground foraging arthropods.
- Using manipulative studies to discern what roles ants play in temperate systems by impacting soil properties, plant communities and populations of pests, decomposes, or other predators.
Ecology of Body Size in Ants
Exploring the origins of body size and its phenotypic variation is fundamental to the study of biology. Phenotypic variation in body size is often the result of reproductive trade-offs. In general, resources are finite and allocated deferentially towards growth, defense, and reproduction. An organism may choose between investing into individual offspring size or total offspring number. For social insects and ants in particular reproductive investment in worker size is important in determining colony establishment, growth, and reproduction (Wills et al. 2018). Colonies potentially optimize body size distributions to their environment due to introduction to novel habitats, or community differences in diet and competition.
To explore how invasion, diet, and competition influence reproductive investment in worker body size, I used two invasive ant species (Pheidole megacephala and Solenopsis invicta) populations. These species were chosen because both contain workers with body size variation, and threaten biodiversity within their introduced ranges. From five populations of P. megacephala, I found populations that encountered the highest diversity of competitors had the largest major and minor workers (Australia) and populations with the lowest diversity of competitors had the smallest major workers (Hawaii) (Wills et al. 2014).
To test how diet influences worker size, I used the continuously polymorphic S. invicta and found a significant increase in mean worker body size and a shift in worker size distributions from colonies supplemented carbohydrates (carbohydrates and carbohydrates & protein) compared to workers not supplemented carbohydrate (water and protein). I also found colonies supplemented carbohydrates had significantly greater biomass and mean worker number than those not supplemented carbohydrate solutions (Wills et al. 2015).
Exploring the origins of body size and its phenotypic variation is fundamental to the study of biology. Phenotypic variation in body size is often the result of reproductive trade-offs. In general, resources are finite and allocated deferentially towards growth, defense, and reproduction. An organism may choose between investing into individual offspring size or total offspring number. For social insects and ants in particular reproductive investment in worker size is important in determining colony establishment, growth, and reproduction (Wills et al. 2018). Colonies potentially optimize body size distributions to their environment due to introduction to novel habitats, or community differences in diet and competition.
To explore how invasion, diet, and competition influence reproductive investment in worker body size, I used two invasive ant species (Pheidole megacephala and Solenopsis invicta) populations. These species were chosen because both contain workers with body size variation, and threaten biodiversity within their introduced ranges. From five populations of P. megacephala, I found populations that encountered the highest diversity of competitors had the largest major and minor workers (Australia) and populations with the lowest diversity of competitors had the smallest major workers (Hawaii) (Wills et al. 2014).
To test how diet influences worker size, I used the continuously polymorphic S. invicta and found a significant increase in mean worker body size and a shift in worker size distributions from colonies supplemented carbohydrates (carbohydrates and carbohydrates & protein) compared to workers not supplemented carbohydrate (water and protein). I also found colonies supplemented carbohydrates had significantly greater biomass and mean worker number than those not supplemented carbohydrate solutions (Wills et al. 2015).
Research as a Teaching Tool
Ants are a tangible model organisms that are easy to collect, maintain, and observe they make excellent subjects for use in undergraduate research projects. My research interests provide ample opportunity for undergraduate engagement, as evidenced by previous co-authorship of undergrads I have mentored. I have always been interested in using research as an instructional tool to give students real world experiences and evidence-based education in the sciences. In assisting, or conducting research, students gain valuable transferable skills in experimental design, managing and analyzing data, and science communication. These skills and experiences help to develop a well-rounded and excellent education in the sciences. My research program will provide an opportunity for undergraduates to drive research focused on elucidating principles in community ecology, behavioral ecology and invasion biology.
Ants are a tangible model organisms that are easy to collect, maintain, and observe they make excellent subjects for use in undergraduate research projects. My research interests provide ample opportunity for undergraduate engagement, as evidenced by previous co-authorship of undergrads I have mentored. I have always been interested in using research as an instructional tool to give students real world experiences and evidence-based education in the sciences. In assisting, or conducting research, students gain valuable transferable skills in experimental design, managing and analyzing data, and science communication. These skills and experiences help to develop a well-rounded and excellent education in the sciences. My research program will provide an opportunity for undergraduates to drive research focused on elucidating principles in community ecology, behavioral ecology and invasion biology.