Dispersal and capacity for adaptive spread in Great Barrier Reef corals
Dispersal via planktonic larval dispersal can link spatially arrayed populations, allowing the exchange of individuals and genetic information. But the scale and directionality of such linkages remain poorly understood. Drawing upon information from spatial genetics, seascape genomics, and biophysical models of dispersal, we are clarifying the nature of these connections among corals on the GBR, especially focusing on a foundational coral species, Acropora tenuis. Using simulations, we are also evaluating the potential for ‘genetic rescue’, that is the spread and assimilation of heat tolerant alleles from warm-adapted source populations. We use a spatially-explicit model of coral adaptation that combines oceanographic estimates of larval dispersal with genetic simulations of single gene and polygenic adaptation. These investigations will identify reefs likely to harbour heat-tolerant coral populations, the relative vulnerability of individual species, and quantify the potential rates of adaptive evolution in reef-building GBR corals.
Resolving the cryptic species identity of native Mytilus mussels and a marine global invader along Australia’s temperate coastlines.
As a successful invasive species, the marine mussel Mytilus galloprovincialis is having profound effects on marine ecosystems worldwide. In Australia, the existence of a morphologically indistinguishable, taxonomically contentious native species, Mytilus planulatus, obscures the extent of M. galloprovincialis establishment and impact. We are resolving the taxonomic status of Australian Mytilus and are developing genetic tools for distinguishing native and invasive species. Our results will clarify whether introduced populations pose a genetic threat to native taxa, and if hybridisation is contributing to the spread of M. galloprovincialis along Australian coastlines.
Arrival and survival an intertidal goby
Most coastal fishes start life as planktonic larvae swimming for days to months before ‘settling’ to the adult habitat. Thus, fish must survive this perilous larval journey and the high mortality transition to adulthood. This begs the question – is the composition of an adult population shaped more by who arrives (larval supply) or by who survives (post-settlement selection)? We have been investigating these dynamics in a highly abundant intertidal fish, Bathygobius cocosensis, examining information derived from otoliths (ear bones showing daily larval growth rates), morphology, physiology, and spatial genomic structure. Despite high and erratic larval supply, we find fine-tuned phenotypic responses to local environments and some evidence for local genetic adaptation.
Potential students with a keen interest in ecological and evolutionary genetics including topics such as adaptation, genomics, hybridization, landscape genetics, biogeography, and macroecology are welcome to make inquiries. PhD students must be competitive for scholarships and come highly recommended in order to be considered: this equates to first class Honours for domestic students and a master’s degree with peer reviewed publications for international students. Honours students have usually taken classes with me at UQ and/or have undertaken undergraduate projects in the lab.
All students should expect to acquire or improve upon skills and proficiency with R and other scripting languages.