Termite Weapons and Warfare: Insights from Behavioral, Experimental, and Evolutionary Analyses

• Main Author: Clifton, Elizabeth Marie
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01-01-2022
• Subjects: Altruism; Animal behavior; Armed forces; Behavioral Sciences; Biology; Birds; Ecology; Ecosystem biology; Entomology; Insects; Mathematical models; Mathematics; Military studies; Mortality; Per capita; Pheromones; Society; Termites; Weapons
• ISBN: 9798382894591

Two opposing forces, competition and cooperation, play vital roles in the evolution of social behavior. Cooperation enables members of social groups to split up tasks, share food, and protect each other. However, groups may also be more prone to competition and predation, as they take up more space and are easier for predators to spot. My work focuses on the defenses social groups have evolved to protect themselves during conflict. Termites provide an ideal system for studying group defense, as their soldier caste, which serves to protect the colony, was one of the first sterile castes to evolve.My initial work used termites to study models of combat based on human warfare, due to termites’ affinity for large, deadly battles. Then, I shifted to more closely study the evolution of termite defenses. My first three chapters analyze Lanchester’s models of combat, which parameterize group size and individual fighting ability to determine the winner of a battle. I staged battles of 50 termites and varied initial group size and group pairings. With collaborators, I analyzed the mortality from these battles to determine if the dynamics if the Lanchester models. I found that group size may weigh heavily in the outcome of intraspecific battles, but interspecific battles have a complicated trade-off between group size and individual fighting ability. I also proposed and found intraspecific support for the synergistic attack hypothesis, which posits that the killing ability of an individual is increased by the presence of its nestmates.My final chapter is a case study of a bizarre defensive adaptation I observed during interspecific battle trials: self-rupturing behavior. Through behavioral assays and microscopy work, I discovered that Cylindrotermes macorgnathus workers self-rupture when threatened and compared their anatomy to their closest relatives, Cephalotermes rectangularis, which don’t rupture. Overall, this dissertation covers the quantitative and qualitative aspects of group fighting and defense in termites.