How do Plant-Insect interactions change along steep environmental gradients?
Ongoing climate change is altering temperature and rainfall, changing the rate of development of organisms, and pushing them closer to their climatic limits and beyond. When these changes become intolerable, plants can persist through adaptation or plasticity, migrate to stay within suitable climates, or die. If the plants migrate, insects that rely on them for all or part of their life cycles are left with similar options: follow their host plants to their new range, shift to a secondary host plant, or die.
I am studying the food web that exists between native Australian legumes, seed-eating insects (typically beetles), and parasitoid wasps. The beetles in this system show an unusual level of host-specificity towards the legumes; each beetle genus typically attacks one legume genus, and sometimes the specificity can be species-to-species. I am using climatic variation along an altitudinal gradient to investigate how climate influences the distribution, assemblage and abundance of species, the trophic structure of the food web, and future changes to that structure. By studying examples of insect-plant specificity, the circumstances that produce it, and what makes it strict or lax, we can arrive at a fuller understanding of the community-level impact of climate change.
Li XM, Blackman CJ, Rymer PD, Quintans D, Duursma RA, Choat B, Medlyn BE, Tissue DT, (2018) 'Xylem embolism measured retrospectively is linked to canopy dieback in natural populations of Eucalyptus piperita following drought', Tree Physiology, vol.38, no.8, pp 1193-1199
Dr Paul Rymer and Professor James Cook