The factors driving historical and contemporary evolution in wild populations are still largely unknown. One of the main challenges in evolutionary biology is to determine how landscape-level geographical and environmental features influence the distribution of this functional adaptive genetic variation. Lobsters from the genus Jasus are a morphologically homogeneous group of ecological and economic importance. These animals have a very long pelagic larval duration (up to 2 years), with the potential for extensive dispersal (Bradford et al. 2015). However, in contrast to predictions all species have a limited distribution and for example J. caveorum has only been found in one single seamount in the eastern South Pacific Ocean (Webber & Booth 1995). Complex fluctuating oceanography such as currents and eddies can influence the genetic partitioning of these species but the factors driving diversification and adaptation of Jasus lobsters are unknown.
The genus is at least as old as the lower Miocene (15-23 Ma) and its origin can be explained by shifts of the southern circumpolar temperate belt towards higher latitudes (George, 1967). Currently, the Jasus genus consists in six species: Jasus edwardsii, J. paulensis, J. caveorum, J. frontalis, J. tristani and J. lalandii (Booth 2006).
Ocean circulation patterns have been changing (e.g. the poleward-flowing East Australian Current) which may affect species dispersal. With a warming climate, native species such as the rock lobsters J. edwardsii may shift poleward while chasing their thermal niche. Therefore, it is crucial to understand the processes responsible for the diversification of these species and their potential for adaptation to environmental change.
This project is funded by a ARC Discovery Grant “Lost at sea? Understanding adaptation and dispersal in spiny lobsters” awarded to Jan Strugnell, Bridget Green and Nicholas Murphy in collaboration with James Bell.
Honours Students – potential projects:
We have two projects available for excellent honours students on the 1) impact of fisheries on genetic diversity and effective population sizes of lobsters and 2) population genomics of the South African West Coast rock lobster. Please contact me or Jan Strugnell if you are interested. In your email, please include a description of your interests and how they fit into our lab along with a CV.
Booth JD (2006) Jasus species. In “Lobsters: Biology, Management, Aquaculture and Fisheries”. (Ed.B. F. Phillips.). Blackwell Scientific Publications: Oxford.
Bradford RW, Griffin D, Bruce BD (2015) Estimating the duration of the pelagic phyllosoma phase of the southern rock lobster, Jasus edwardsii (Hutton). Marine and Freshwater Research, 66, 213–219.
George RW (1967) Natural distribution and speciation of marine animals. J. R. SOC. West. Aus., 52, 33–40.
Webber WR, Booth JD (1995) A new species of Jasus (Crustacea: Decapoda: Palinuridae) from the eastern South Pacific Ocean. New Zealand Journal of Marine and Freshwater Research, 29, 613–622.
Cover photo: Stemonitis