Ant traits, myrmecophiles, and disturbance

Abstract 350 words maximum (PLEASE TYPE)Ants are eusocial insects that are diverse, abundant, and globally widespread. These attributes allow ants to play an important role in terrestrial ecosystems; such as significantly contributing to soil turnover, predator-prey relationships, and facilitating biodiversity. This thesis examines how environmental factors and species traits, play a role in determining symbiotic relationships, as well as determining resilience to disturbance. Chapter 1 looks at why ants are good focal taxa to study a wide range of ecological questions including symbiotic associations, climatic influence in species richness, and habitat disturbance on communities. Chapters 2, 3, and 4 involved a database of ants and myrmecophiles, synthesized by me from 351 references, that included 622 ants and 1629 myrmecophiles. In Chapter 2, I examined if the global species richness of myrmecophiles and their symbiotic relationships, was determined by regional ant species richness or climatic variables associated with a latitudinal gradient. I found that both ant species richness and climatic variables influenced myrmecophile richness, but richness of symbiotic relationships were more affected by climatic variables. In Chapter 3, I looked at ant traits such as colony size, diet or morphological traits and determined which were correlated with more myrmecophile associations. I found that large colony size (>1000 000) and number of spines, played an important role in explaining the number of myrmecophiles associated with an ant. Chapter 4 models the host range of different myrmecophile relationships at the species level, contrasting relationship type and taxonomic group to determine if myrmecophiles with beneficial or detrimental relationships have more hosts. I found that beneficial relationships had a higher number of associations compared to detrimental ones. For Chapter 5, I did a field study looking at the effects of grazing intensity and history on below- and aboveground ant communities within the arid woodlands of New South Wales. I found that below-ground communities were resilient to grazing disturbance, and that grazing history had a greater affect on above-ground communities than grazing intensity. Chapter 6 summarizes my findings, discusses the implications of my work, the limitations of the studies, and suggests future paths of research on ants and myrmecophiles