Faculty of Science, Engineering and Built Environment
School of Life and Environmental Sciences
Evolutionary and pest biology of the invasive North Pacific sea star, Asterias amurensis, in Australia
Participants: Dr Craig Sherman (PI), Dr Ben Hayes (Department of Primary Industries)
Aims and background: Invasive species are now recognised as one of the most serious threats to Australia's biodiversity. While substantial work has been carried out on the ecology of invasive species, the evolutionary genetics of invasive species has received less attention. However, it is becoming increasingly evident that the establishment and spread of exotic species can be influenced by their adaptive potential and that effective control requires an understanding of the evolvability of invasive species.
The invasive North Pacific Sea Star is a ferocious marine predator and has the potential to have a devastating effect on Australia's aquaculture industry and significantly reduce the biodiversity of marine communities. It is estimated that there are more than 90 million in Port Phillip Bay, with the potential for this species to occupy even larger areas from Sydney to Perth. In spite of being listed as one of the ten highest marine risk pests in Australia, virtually nothing is known about its potential for local adaptation and what may constrain its progression along the east and southwest coasts of the continent. This project will provide crucial information on the evolutionary biology of this species and identify key life history traits important for the successful management of this invasive species.
Specifically, this project will address the following aims:
- Determine the amount of additive genetic variation and heritability of life-history traits that promote range expansion, by comparing invasive versus native populations
- Experimental (rapid) evolution of life history traits that may facilitate range expansion
- Adaptations in the wild: population genetics of life history traits of the North Pacific sea star from invasive versus non-invasive populations
Scientific significance and innovation: To date the effective control of invasive species in most countries has been met with limited success, partly because crucial aspects of their evolutionary biology have been ignored. However, by analysing genetic architecture, inheritance, and ongoing selection, we can not only understand evolutionary processes in the wild, but also predict future changes in traits that are relevant for invasion. Such knowledge is fundamentally important for making risk assessments of for invasive species.
This project is innovative in using an evolutionary approach to understand invasion biology, and holds great promise for identifying the proximate and ultimate mechanisms needed for successful invasion. Invasive species offer significant opportunities to study basic processes in evolutionary biology. They provide a natural experiment to test fundamental evolutionary theory while providing applied outcomes for management and conservation.
Potential national benefit and strategic alignment with the aims of the CIE: Protecting Australia from invasive pest species is a national priority goal ((Safeguarding Australia: Protecting Australia from invasive diseases and pests) and a direct target of this project. This project is also strongly aligned with the CIE's research priorities. This project will assess the relative importance of evolvability in proximate mechanisms (e.g., temperature tolerance) by understanding thermal tolerance at the individual and gametic level, the heritability and distribution of these traits at the population level, and finally evolutionary change through the use of artificial selection experiments
