Maintaining a healthy and biologically diverse marine environment is essential for sustaining economical development. This is particularly true in Australia, an island nation with the world’s largest area of ocean territory. Systematic discussions about marine biodiversity usually converge on a single topic: the dispersal of marine organisms. Dispersal (often known as genetic connectivity) is perhaps the major force shaping species distribution, persistence and evolution and represents a critical factor when developing management strategies for fishery resources, implementing aquaculture initiatives, or designing marine protected areas (MPAs). Data on dispersal of marine organisms has been very difficult to acquire, not least because of the problems of observing direct movements in the sea. However, recent advances in genomics and statistical analyses have revolutionized the way we make inferences about the biology of marine organisms – researchers are now capable of addressing consequential questions about dispersal, stock management and evolution in the sea that could not be realistically formulated few years ago. Those include assessments of the biological consequences of rapid climate change in marine waters of Australia, which in some regions are warming at over four times the global ocean warming average.
MEGMAR (the Molecular Ecology Group for Marine Research) combines research expertise in marine ecology, conservation management, oceanography and molecular ecology to address questions about marine biodiversity relevant to a range of marine stakeholders including scientists, educators, government departments and commercial and recreational fishermen. It represents the first molecular ecology group in Australia with a focus on connectivity, fisheries genomics, seascape genomics and evolution in the sea. Our multi-institutional research program initiated in 2005 in Sydney, with funding from Macquarie University. It is now based in Adelaide and it has received funding by an ARC Discovery (DP110101275, Beheregaray, Möller & Waters 2011-2013), by an ARC Linkage (LP180100756, Beheregaray et al. 2021-2023), by various fisheries contracts and grants and by Flinders University.
ur main focus is on connectivity, fisheries genomics and seascape genomics of temperate marine animals – these are areas we have pioneered and lead in Australia. Seascape genomics (or seascape genetics) is the joint analysis of high-resolution population genomic data and marine environmental data. Our studies have assessed the relative roles of history, temperature and transport in shaping population connectivity and range shifts. For instance, we have shown that variation in ocean current circulation, through its influence on larval transport and recruitment or on prey distribution, can generate reduced connectivity in species capable of long distance dispersal. Most of these studies (listed below) were on species sampled along the east coast of Australia. Our discovery that ecologically dissimilar species display similar localized structure opens an exciting area for comparative research in the sea and strengthens the idea that oceanography can be used to predict biotic connectivity.
Our publications in this field include studies on mollusks (Piggott et al. 2008 MEPS; Teske et al. 2011; Waters et al. 2014 MFR), sea-urchins (Banks et al. 2007 Ecology; Banks et al. 2010 Molecular Ecology), common-dolphins (Bilgmann et al. 2007 MEPS; Bilgmann et al. 2008 Animal Conservation; Möller et al. 2011 Marine Biology; Amaral et al. 2012 PLoS ONE), bottlenose dolphins (Möller et al. 2007 MFR; Wiszniewski et al. 2010 Conservation Genetics; Bilgmann et al. 2011 PLoS ONE; Amaral et al. 2012 Molecular Ecology), tunicates (Teske et al. 2011 BMC Evol Biol; Teske et al. 2014 Ecol & Evol); sharks and coastal teleosts (Corrigan et al. 2008 J Fish Biology; Teske et al. 2010 Marine Biology) and other organisms.
We have also tackled long-standing questions in marine evolution, biogeography and taxonomy by sampling collaboratively over different ocean basins and analyzing multilocus datasets with recently developed frameworks in statistical phylogeography and phylogenetics. Some key findings include (i) a biogeographic hypothesis for the evolution of the upright posture in sea horses (Teske & Beheregaray 2009 Biology Letters), (ii) how divergent selection due to historical changes in oceanography drive speciation in limpets (Teske et al. 2011 Molecular Ecology), (iii) how “nested” cryptic diversity in a cosmopolitan ecosystem engineer exemplifies major challenges for understanding invasion and managing marine biodiversity (Teske et al. 2011 BMC Evol Biol), (iv) phylogenetic and biogeographic support for a recent radiation in an iconic shark group (Corrigan & Beheregaray 2008 MPE), (v) how past climatic changes rule out ‘Gondwanan origins’ for coastal crabs (Teske et al. 2009 MPE), (vi) a multilocus evidence for a new dolphin species in Australia (Möller et al. 2008 MPE).