University of Vermont

The College of Arts and Sciences

Department of Biology

Research Affiliate - Ken Helms

Ken Helms

Ken Helms, Research Affiliate

  • Ph.D., Arizona State University, 1994
  • Postdoctoral: Arizona State University 1995-1996, Texas A&M University 1998-2000, University of Lausanne 2000-2002
  • Texas A&M University 2002-2004, Assistant Research Scientist
  • University of Vermont 2004-12, Research Assistant Professor
  • University of Vermont 2012, Research Affiliate
Area of expertise

ecology and evolution

Contact Information
Email: Ken Helms

Office Hours: by appointment
Marsh Life Science Building, Rm 328
Phone: (802) 656-9012

Website for LAB



Research in the Helms laboratory uses social insects as model systems to develop and test basic theory in ecology and evolution. The laboratory addresses questions of broad significance, often on large geographic scales. Projects range from the study of sex ratio evolution in social insects, to the importance of ecological interactions among invasive species, to studies of the evolution of cooperation, conflict and cooperative breeding. While we make extensive use of modern techniques from fields such as molecular genetics, phylogeography, and geographic information systems, our research is grounded in the importance of understanding the natural history of species in their environment.

Selected Publications

  • Helms, K.R., 2013. Mutualisms between ants (Hymenoptera: Formicidae) and honeydew-producing insects: Are they important in ant invasions. Myrmecological News 18: 61-71.
  • Helms, K.R., & S. Helms Cahan. 2012. Large-scale regional variation in cooperation and conflict among queens of the desert ant Messor pergandei. Animal Behaviour 84: 499-507.
  • Helms Cahan, S. & K.R. Helms. 2012. Relatedness does not explain geographic variation in queen cooperation in the seed-harvester ant Messor pergandei. Insectes Sociaux 59: 579-585.
  • Abbot, P., Abe, J., Alcock, J., et al., Helms, K.R., et al. 2011. Inclusive fitness theory and eusociality. Nature 471: E1-E4.
  • Helms, K.R., Hayden, C.P. & S.B. Vinson, 2011. Plant-based food resources, trophic interactions among alien species, and the abundance of an invasive ant. Biological Invasions 13: 67-79. (Full text PDF)
  • Helms, K.R. & S.B. Vinson. 2008. Plant resources and colony growth in an invasive ant: The importance of honeydew-producing hemiptera in carbohydrate transfer across trophic levels. Environmental Entomology 379: 487-493. (Full text (PDF))
  • Helms, K. R., M. Reuter & L. Keller. 2005. Sex-ratio conflict between queens and workers in eusocial Hymenoptera: mechanisms, costs, and the evolution of split colony sex ratios. Evolution 59: 2626-2638. (Full text (PDF))
  • Kummerli, R., K. R. Helms & L. Keller. 2005. Experimental manupulation of queen number affects colony sex ratio investment in the highly polygynous ant Formica exsecta. Proceedings of the Royal Society of London, B: Biological Sciences 272: 1789-1794. (Full text (PDF))
  • Reuter, M, K. R. Helms, L. Lehmann & L. Keller. 2004. Effects of brood manipulation costs on optimal sex allocation in social Hymenoptera. American Naturalist 164: E73-E82. (Full text (PDF))
  • Helms, K. R., D. Fournier, L. Keller, L. Passera & S. Aron. 2004. Colony sex ratios in the facultatively polygynous ant Pheidole pallidula: A reanalysis with new data. Evolution 58: 1141-1142. (Full text (PDF))
  • Helms, K. R. & S. B. Vinson. 2003. Apparent facilitation of an invasive mealybug by an invasive ant. Insectes Sociaux 50: 403-404.(Full text (PDF))
  • Helms, K. R. & S. B. Vinson. 2002. Widespread association of the invasive ant, Solenopsis invicta, with an invasive mealybug. Ecology 83: 2425-2438. (Full text (PDF))
  • Helms, K. R., J. H. Fewell & S. W. Rissing. 2000. Sex ratio determination by queens and workers in the ant Pheidole desertorum. Animal Behaviour 59:523-527. (Full text (PDF))
  • Helms, K.R. 1999. Colony sex ratios, conflict between queens and workers, and apparent queen control in the ant Pheidole desertorum. Evolution 53:1470-1478. (Full text (PDF))
  • Cahan, S., K. R. Helms & S. W. Rissing. 1998. An abrupt transition in colony founding behaviour in the ant Messor pergandei. Animal Behaviour 55:1583-1594. (Full text (PDF))
  • Helms, K.R. 1994. Sexual size dimorphism and sex ratios in bees and wasps. American Naturalist 143:418-434. (Full text (PDF))