Mr Matt Elmer1, Dr Vanessa Kellermann1,2, Dr Keyne Monro1

1Monash University, Clayton, Australia, 2La Trobe University, Bundoora, Australia

Biography:

Matt is a PhD candidate at Monash University, supervised by Vanessa Kellermann and Keyne Monro. He is particularly interested in ecology, evolution and genetics, and is fond of using integrative approaches to answer scientific questions. Throughout his PhD he has used a combination of field work, lab work and experiments to study physiological traits, phenotypic plasticity, and population genomics of Australian native bees. He is also interested in ecological modelling. Prior to starting his PhD, Matt completed his undergraduate studies at the University of Queensland, and his Honours degree at Flinders University with A/ Prof Mike Schwarz. He has also worked as a Research Assistant at CSIRO, the University of Queensland and the University of Melbourne in the fields of entomology, agriculture and conservation.

Abstract:

Native bees are important pollinators, but they are declining globally, due to stressors such as habitat loss, pesticide use, and climate change. Yet, despite the importance of native bees, we know very little about how they will respond to changing climates. In the current study we investigate how two key traits, known to be associated with distributions, cold tolerance and heat tolerance, vary across populations in a species of Australian native bee, Exoneura robusta. We leverage natural environmental gradients along the east coast of Australia (latitude and elevation) to determine the total variation in these traits in the field. We repeat these measures in the same populations across seasons, to measure the capacity of the species to shift traits in response to climate over short time scales. To gain insight into genetic and plastic contributions to these traits, we undertook a 24-day adult acclimation experiment in two temperature treatments. We found that many populations were able to shift traits across seasons, which is important for responding to climate change on short time scales. We also found that phenotypic plasticity is likely the main driver of trait variation in the field, after finding little evidence of possible genetic differences between populations from our adult acclimation experiment. Additionally, the most northern population had relatively poorer cold and heat tolerance, suggesting that northern populations may be the most threatened by changing climates. Understanding how bees will respond to changing climates is crucial for maintaining healthy natural and agricultural ecosystems into the future.