Newsletter Issn 1834-4259 No

NEWSLETTER ISSN 1834-4259 NO. 150 APRIL 2014

Integrating cell biology and climate change: can oysters adapt to ocean acidification? Priscila Goncalves, Macquarie University, Sydney, NSW Email: [email protected]

Increasing concentrations of anthropogenic atmos- levels. In addition, the selectively bred oysters have pheric carbon dioxide (CO2) have been driving higher standard metabolic rates (SMR) under ambi- changes in ocean acidity and temperature over the ent conditions, and their SMR is further increased past 150 years. Elevated CO2 concentrations are by high CO2. My PhD research exploits this unique predicted to cause a reduction in the ocean surface genetic resource: a selectively bred population of pH from 8.1 to 7.8, as well as a decrease in car- Sydney rock oyster that is better equipped to with- bonate ion concentrations by 2100 (IPCC 2013). stand ocean acidification and shows signs of adapta- Southeast Australia has been identified as a climate tion to climate change. change hotspot, where the ocean is changing faster The potential for genetic adaptation to cli- than the global average (Poloczanska et al. 2007). mate change in marine organisms has been poorly This changing ocean is particularly damaging to explored. To date, most studies of ocean acidifica- molluscs, since they are a major producer of calcium tion have only focused on the impact of this stress carbonate shells, which are susceptible to altered on calcification, reproduction and early development carbon chemistry. (Kroeker et al. 2013). In contrast, my project is in- The impact of climate change on marine vestigating the biological mechanisms that allow the organisms can vary depending on the species, and selectively bred population of Sydney rock oysters to even between populations within species. A recent become resilient to ocean acidification. study that evaluated the susceptibility of different Using a variety of molecular approaches, fisheries species to climate change suggested that our research group has identified biological path- Sydney rock oysters (Saccostrea glomerata) are at the ways responsible for a range of biological functions greatest risk (Doubleday et al. 2013). This is of par- that are commonly affected by environmental ticular concern because Sydney rock oysters are key- stressors. stone species in many environments and are also the focus of a major aquaculture industry. Hence, impacts on the oysters may significantly affect both marine ecosystems and aquaculture production nationwide. However, new evidence suggests that some populations of Sydney rock oyster have differential responses to climate change in their early develop- mental stages. The deleterious effects of climate change are far less severe in a population of oysters produced by selective breeding for fast growth and resistance to disease compared to wild type (non- selected) oysters. Parker et al. (2011, 2012) found that larvae from these selectively bred oysters have significantly higher survival rates and grow twice as Sydney rock oyster, Saccostrea glomerata, specimens. Photo: Gabriel Fonseca. fast as wild type oysters when exposed to high CO2 1 (Continued on page 3)

Society information

President Rachel Przeslawski Membership fees 2014 Vice President Kirsten Benkendorff Includes Molluscan Research (published four times per Treasurer Don Colgan year) the MSA Newsletter and discounted registra- Secretary Carmel McDougall tion at the Molluscs 2015 conference. Membership Secretary Kathleen Hayes Public Relations Officer Caitlin Woods Ordinary members (Aust., Asia, w. Pacific) $A70 Journal Editor Winston Ponder Ordinary members (rest of the world) $A100 Newsletter Editors Mandy Reid Extra family member $A5 Jonathan Parkyn Affiliate organisation $A100 Website Administrator Shane Penny Student member/concession $A45 Council Members Simon Hills Jonathan Parkyn Membership fees can be paid (preferably) via the Platon Vafiadis Society’s website.

All enquiries and orders should be sent to the Send subscriptions via mail to: Malacological Society Secretary, Carmel McDougall, at of Australasia, c/o Kathleen Hayes, 8 Hordern Rd, [email protected] Mt Evelyn, VIC 3796.

Newsletter Victorian branch Editors: Mandy Reid, Malacology Department, Secretary Michael Lyons, 19 Banksia Street, Black- Australian Museum, 6 College St, Sydney, NSW burn, VIC 3130. Phone (03) 9894 1526 or Email: 2010. Phone (02) 9320 6412. [email protected]. Meetings at the Email: [email protected] and Melbourne Camera Club, cnr Dorcas and Farrars Jonathan Parkyn, Streets, South Melbourne, on the third Monday of Email: [email protected] each month. No meeting in January, July or December. Deadline for articles for the next issue of the News- letter: 20 June 2014.

MSA website http://www.malsocaus.org This publication is not deemed to be valid for taxonomic purposes (See article 8.2 in the International http://www.facebook.com/ Code of Zoological Nomenclature 4th Edition.) groups/Malsocaus

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determine whether these stress response pathways are affected by elevated CO2 concentrations. This is in an effort to identify the cellular mechanisms involved in the improved performance of selectively bred oysters. By analysing cellular structures and processes that are often susceptible to environmental stress, I will be able to determine the molecular mechanisms that contribute to CO2 susceptibility and tolerance in molluscs. The identification of these key processes will provide a functional framework to explain genetic adaptation to climate change.

References Doubleday, Z.A. et al. (2013). Aquaculture Environment Interactions 3, 163–175. Sydney rock oyster blood cells stained with fluorescent probes Intergovernmental Panel on Climate Change, IPCC (2013). viewed under a confocal microscope. Photo: Priscila Goncalves. Cambridge Univ Press, Cambridge, UK, 2216 pp. Kroeker, K.J. et al. (2013). Global Change Biology 19, 1884–1896. Parker, L.M. et al. (2011). Marine Biology 158, 689–697. I am currently investigating the impacts of high CO2 Parker, L.M. et al. (2012). Global Change Biology 18, 82–92. levels on these processes in both selectively bred Poloczanska, E.S. et al. (2007). Marine Biology Annual Review 45, 407–478. and wild type oyster populations. Adults of selectively bred and wild type (non-selected) oyster populations are being compared at a cellular level to

Mollusc research grants

Applications for the MSA Mollusc Research Grants are currently being accepted. The deadline for this year is 30th June, 2014. Applications are encouraged from postgraduate research students and early career research- ers. Up to $2000 is available to assist with costs associated with field trips or research consumables.

We are pleased to announce that, due to a generous anonymous donation, an additional grant of $1000 will be available this year to support student research into molluscan taxonomy. If the project is taxonomic in nature, applications will automatically be considered for this taxonomic grant, as well as the general Mollusc Research Grants.

To apply, candidates should email the following to Dr Kirsten Benkendorff at [email protected]:  A research proposal, including: 1) the project title, 2) brief background to place the study in context, 3) aims and objectives, 4) approach and methodology, 5) expected outcomes, 6) references, and 7) itemised project budget with brief justification. (Four page limit.)  Curriculum vitae, including current position, educational qualifications, research track record and the names and addresses of two referees to whom the committee may refer.

Please note that these MSA grants are highly competitive and preference will be given to well-designed pro- jects that will significantly advance our knowledge of Australasian molluscs. The scope of the proposal should be commensurate with the budget and/or other sources of available funds. Successful applicants will be required to accept the award within two months and should provide an article for the MSA Newsletter within 12 months.

Further details including eligibility criteria can be found at: www.malsocaus.org/research_support.htm

Notes on the Truncatelloidea (Gastropoda : Caenogastropoda) in Australia Anders Hallan, Australian Museum Research Institute, Sydney, NSW Email: [email protected]

The superfamily Truncatelloidea Gray, 1840 is a widespread in Australia, yet these considerable geo- comparatively large group of small to minute cae- graphic ranges have only recently been recognised nogastropods of which approximately 15 families are (Ponder et al. in press, Fukuda et al. in press). Such represented in Australia. Truncatelloideans are char- findings emphasise the need for more basic acterised by their small non-siphonate shells that knowledge, even for species that are seemingly wide- usually have limited sculpture and simple rounded ly distributed. apertures, and their radulae are taeniglossate. How- However, there have been significant ad- ever, synapomorphies are difficult to identify and vances in the taxonomy of Australian truncatelloide- they have only recently been considered separately an gastropods, and these advances in turn contribute from the superfamily Rissooidea, such as in a molec- to more informed conservation and management ular study by Criscione and Ponder (2013). efforts. In recent years (and ongoing), knowledge of, In Australia, truncatelloideans occur in a for instance, tateids, assimineids and iravadiids has range of environments, from open marine to estua- increased exponentially. Some families previously rine, freshwater and fully terrestrial. Some families believed to be depauperate have, in the light of re- are particularly abundant in tropical to temperate cent studies, revealed significant diversity. To illus- mangroves, such as the Assimineidae, Stenothyridae trate, prior to 1980, 29 tateids were described from and Iravadiidae (Fukuda and Ponder 2003, Golding Australia compared to the 190 species (in 15 genera) in press a, b). In freshwater, the Tateidae (of the Hy- described since then (Ponder, pers. comm.). Among drobiidae sensu lato) is remarkably diverse, and singu- assimineids, 30 years ago, only one genus was larly constitutes the great majority of known Austral- thought to live in Australia, whereas today we know ian freshwater gastropods, including over 100 taxa of nine genera occurring in mainland Australia and yet to be described (Ponder pers. comm.). Tasmania, four of which are presumed endemic to Due to their size and the relatively inhospi- the country (e.g. Fukuda and Ponder 2003, 2005). table, often remote situations in which they occur, Recent revisions have also been made to Australian the study of truncatelloideans is challenging, howev- Stenothyridae and Iravadiidae (Golding in press a, er, vitally important. Estuarine and freshwater trun- b), and following these studies potential new fami- catelloideans face unprecedented threats from hu- lies have emerged. Truncatelloidean families de- man development and climate change. As an exam- scribed in Australia include the Calopiidae (Ponder ple, an estimated 60% of species of Australian 1999) and the Indo-Pacific Clenchiellidae (Ponder et Tateidae registered on the IUCN Red List are con- al. in press). sidered threatened (http://www.iucnredlist.org/), a figure likely to be an underestimate. This dire situa- tion is reflected globally—freshwater gastropods constitute only 5% of all gastropod species yet ac- count for 20% of all molluscan extinctions (Strong et al. 2008). Often neglected in favor of their marine counterparts, freshwater and estuarine gastropods (and particularly micro-gastropods) are therefore in urgent need of comprehensive cross-disciplinary study to ensure their future diversity. Distribution patterns seen in Australian truncatelloideans vary considerably. Some occur in very narrow ranges, even in single localities, such as tateids in remote freshwater springs of South Aus- tralia and Queensland (Ponder et al. 1989; Ponder and Clark 1990), clenchiellids confined to narrow sections of the tropical Daly River (Ponder et al. in press), and a lone assimineid only found in volcanic scree on the northwestern slope of a Kimberley island (Hallan and Fukuda in prep.). Conversely, An undescribed species of terrestrial Assimineidae from an Clenchiella minutissima and Taiwanassiminea affinis are island off the Kimberley coast, Western Australia. Photo: A. Hallan. 4

A considerable part of these studies have been con- Golding, R.E. (in press a). Molecular phylogeny and systematics ducted at the Australian Museum, Sydney. Personal- of Australian ‘Iravadiidae’ (Caenogastropoda: Truncatelloi- ly, I have only recently joined such studies, some of dea). Molluscan Research Golding, R.E. (in press b). Molecular phylogeny and systematics which go back decades. Currently, my colleagues of Australian and East Timorese Stenothyridae (Winston Ponder, Michael Shea and Francesco (Caenogastropoda: Truncatelloidea). Molluscan Research Criscione) and I work on the families Assimineidae, Ponder, W.F. (1999). Calopia (Calopiidae), a new genus and family Tateidae, Calopiidae and Clenchiellidae. of estuarine gastropods (Caenogastropoda: Rissooidea) from Australia. Molluscan Research 20, 17–60. Ponder, W.F. and Clark, G.A. (1990). A radiation of hydrobiid References snails in threatened artesian springs in western Queensland. Criscione, F. & Ponder, W.F. (2013). A phylogenetic analysis of Records of the Australian Museum 42, 301–363. rissooidean and cingulopsoidean families (Gastropoda: Ponder, W.F., Hershler, R. & Jenkins, B. (1989). An endemic Caenogastropoda). Molecular Phylogenetics and Evolution 66, radiation of hydrobiid snails from artesian springs in north- 1075–1082. ern South Australia: their taxonomy, physiology, distribution Fukuda, H. & Ponder, W.F. (2003). Australian freshwater assimin- and anatomy. Malacologia 31, 1–140. eids, with a synopsis of the Recent genus-group taxa of the Ponder, W.F., Fukuda, H. & Hallan, A. (in press). A review of the Assimineidae (Mollusca: Caenogastropoda: Rissooidea). family Clenchiellidae (Mollusca: Caenogastropoda: Trun- Journal of Natural History 37, 1977–2032. catelloidea). Zootaxa Fukuda, H. & Ponder, W.F. (2005). A revision of the Australian Strong, E.E., Gargominy, O., Ponder, W.F. & Bouchet, P. taxa previously attributed to Assiminea buccinoides (Quoy & (2008). Global diversity of gastropods (Gastropoda: Mol- Gaimard) and Assiminea tasmanica Tenison-Woods (Mollusca: lusca) in freshwater. Hydrobiologia 595, 149–166. Gastropoda: Caenogastropoda: Assimineidae). Invertebrate Systematics 19, 325–360. Fukuda, H., Ponder, W.F. & Hallan, A. (in press). Anatomy, rela- tionships and distribution of Taiwanassiminea affinis (Böttger) (Caenogastropoda: Assimineidae), with a reassessment of Cyclotropis Tapparone-Canefri. Molluscan Research

Evolution, gene expression and enzymatic production of Tyrian purple: A molecular study of the Australian muricid Dicathais orbita (Neogastropoda: Muricidae) Patrick Laffy, Australian Institute of Marine Science Email: [email protected]

Tyrian purple is the traditional source of purple pig- mentation used in the textile industry since ancient times, sourced from the Muricidae family of neogas- tropod molluscs. Brominated indole derivatives of tryptophan, the precursors to Tyrian purple, are po- tent anticancer and antibacterial compounds that may have potential for pharmaceutical development. In addition to their production within the hypobranchial gland, some members of the Muricidae have been shown to invest Tyrian purple precursors within their egg capsules in order to chemically defend their developing embryos from pathogenic attack. One of the aims of my PhD thesis was to investigate the evolution of Tyrian purple precursor investment within the egg masses of muricid molluscs using mo- Fig. 1. Dicathais orbita with freshly laid (cream) and well lecular phylogenetic analysis of 18s and 28s riboso- developed (purple) egg capsules. Photo: P. Laffy. mal RNA sequences. An additional aim was to investigate the gene expression of the hypobranchial gland of the Australian muricid Dicathais orbita (Fig. tion of the Muricidae. Our molecular analysis identi- 1), in an effort to uncover the enzymes involved in fied the monophyly of the Rapaninae and the production of Tyrian purple. Ocenebrinae muricid subfamily members investigat- Our investigation into the evolution of Tyri- ed in this study and supports Tan’s (2003) classifica- an purple precursor investment within the egg cap- tion of a new muricid subfamily, the Haustrinae. sules (Fig. 1) of muricid molluscs has shown that the These findings also support the use of D. orbita as a investment of these compounds is a trait that is not representative of the Rapaninae in which to study ancestral and has arisen at least twice in the evolu- Tyrian purple synthesis and investment. 5

In order to investigate the gene expression of the annotation. Sequence annotation indicated the hypo- hypobranchial gland of D. orbita, suppressive sub- branchial gland plays a key role in muricid biology as tractive hybridization (SSH) was used to identify a site of chemical interaction and biosynthesis, and genes that were up-regulated or uniquely expressed suggested it is involved in the reproductive processes in the gland. A total of 438 sequences were identi- of muricid molluscs (Laffy et al. 2013). Manual se- fied to be differentially expressed in the hypobran- quence annotation identified a number of sequences chial gland, including an arylsulfatase gene. Aryl- within our cDNA library using an alternate codon sulfatase activity had previously been identified to be translation system employed by ciliate protozoans, involved in the formation of Tyrian purple from and histological analysis of the hypobranchial gland precursors in muricid molluscs. The full length aryl- identified intracellular ciliate protozoans present sulfatase sequence was amplified and recombinantly within the gland (Fig. 2). Ciliate abundance varied expressed in a mammalian expression system. While according to the reproductive condition of the host a full length protein sequence was identified from snail and 45 ciliate protein coding genes were identi- expression studies, no active enzyme was produced fied within our cDNA library. Analysis of ribosomal from these experiments suggesting an incompatibil- RNA sequenced from our expression library identi- ity between molluscan arylsulfatase and mammalian fied the presence of two separate ciliate protozoans expression systems. within the hypobranchial gland of D. orbita belonging Initial manual sequence analysis indicated to the ciliate classes Suctoria and either Protostoma that over 65% of sequences produced showed no or Litostomatea. homology to known database sequences, and se- In summary, this thesis used molecular tech- quence matches showed homology to a wide variety niques to explore the synthesis and evolution of Tyr- of taxa, including chordate, molluscan and ciliate ian purple synthesis and related gene expression in sequences (Laffy et al. 2009). Our investigation of the muricid mollusc D. orbita. It is the first study to gene expression in the hypobranchial gland of D. investigate the evolution of Tyrian purple precursor orbita facilitated the functional assignment of 115 investment within the egg capsules of muricid mol- sequences using BLAST2GO automated sequence luscs and has revealed that this is a derived trait that has arisen at least twice since the muricids diverged from other Muricoidean species. In addition, it is the first study to investigate gene expression within the hypobranchial gland of any mollusc and is the largest molecular investigation performed on any muricid mollusc. This study also identified one of the gene sequences involved in the enzymatic production of these bioactive compounds. Additional investigations are required to identify the other enzymes involved in the production of Tyrian purple precursors, which would then facilitate the in vitro synthesis of these compounds in the future. If sustainable synthesis of these compounds is established, these bioactive compounds may find use in pharmaceutical or nutraceutical treat- ments.

References Laffy, P.W., Benkendorff, K. & Abbott, C.A. (2009). Trends in molluscan gene sequence similarity: An observation from genes expressed within the hypobranchial gland of Dicathais orbita. The Nautilus 123: 154–158. Laffy, P., Benkendorff, K. & Abbott, C.A. (2013). Suppressive subtractive hybridization transcriptomics provides a novel insight into the functional role of the hypobranchial gland in a marine mollusc. Comparative Biochemistry and Physiology Part D Genomics 8: 111–122. Tan, K.S. (2003). Phylogenetic analysis and taxonomy of some Fig. 2. Transverse section of the hypobranchial gland of southern Australian and New Zealand Muricidae (Mollusca: Dicathais orbita stained with Toluidine Blue displaying Neogastropoda). Journal of Natural History 37: 911–1028. numerous intracellular ciliates in the subepithelium. Photo: C. Westley.

Can oysters build resilience of coastal biodiversity to environmental change? Dominic McAfee, Department of Biological Sciences, Macquarie University, Sydney, NSW Email: [email protected]

Coastal ecosystems are recognised as among the most valuable ecosystems worldwide, supporting economically significant fisheries, protecting coast- lines from erosion, and are essential for nutrient cy- cling and anthropogenic waste management. In- creasingly, these ecosystems are under threat from the interacting effects of climate change and coastal development. Intertidal organisms are particularly vulnerable to environmental change as they already live close to the edge of their physiological toleranc- es (e.g. Stillman and Somero 2000). Therefore, novel management strategies are required to help these ecosystems endure future environmental change and curtail biodiversity loss. Ecosystem engineers—species that modify local environmental conditions via their physical structures—could provide refugia to associated organisms from changing environmental conditions (Byers et al. 2006). On the east coast of Australia the Sydney rock oyster could provide such refuge because it is the key ecosystem engineer in many estua- This experiment is being used to assess the ability of oysters to rine habitats. Oysters can support diverse biological grow, survive and form habitat under different temperature communities as their structures provide substratum regimes. Panels with different thermal absorption properties for attachment, protection from predators, buffer are used to manipulate temperature in the field. physical disturbance (i.e. waves) and accumulate nu- Photo: D. McAfee trient rich sediments (Gutierrez et al. 2003). In the intertidal zone, oysters create microhabitats that are provided by oysters will continue to support dense cooler and more humid than adjacent bare rock as and diverse communities of invertebrates. their structures provide shade, retain water and accu- It will make use of wild type Sydney rock oys- mulate moist sediments. The ability of oysters to ters as well as oysters selectively bred for stress re- buffer the effects of environmental change on sistance. I predict that selectively bred oysters will coastal biodiversity will, however, depend on the maintain habitat for invertebrates across a broader mechanisms by which oysters build resilience in in- range of environmental conditions than wild type vertebrate communities and the ability of oysters to oysters. The study will hence assess whether selec- adapt to change. tively bred oysters could be used in restoration pro- The first component of my PhD research jects to build even more effective refuges from envi- will determine whether natural oyster beds can pro- ronmental change for associated organisms. tect coastal ecosystems from the effects of environ- The outcomes of this research will aid con- mental change by establishing when and where oys- servation and restoration efforts aimed at preserving ters facilitate and build resilience among associated Australia's highly endemic coastal biodiversity and organisms. Field experiments manipulating heat and its important ecosystem functions. desiccation stress, and predator access across a lati- References tudinal gradient will be used to determine the Byers, J. E., Cuddington, K., Jones, C. G., Talley, T. S., Has- sources of lethal and sub-lethal stress to marine in- tings, A., Lambrinos, J. G., Crooks, J. A. & Wilson, W. G. (2006). Using ecosystem engineers to restore ecological vertebrates, and the extent to which facilitation of systems. Trends in Ecology and Evolution 21: 493–500. biodiversity by oysters is a consequence of the re- Gutierrez, J. L., Jones C. G., Strayer, D. L. & Iribarne O. O. duction in abiotic and biotic stressors. (2003). Mollusks as ecosystem engineers: the role of shell The second component of this research will production in aquatic habitats. Oikos 101: 79–90. assess how warmer temperatures will affect the abil- Stillman, J. H. & Somero, G. N. 2000. A comparative analysis of the upper thermal tolerance limits of eastern Pacific porce- ity of oysters to persist and form habitat, and wheth- lain crabs, genus Petrolisthes: influences of latitude, vertical er, under such conditions, the microhabitats zonation, acclimation, and phylogeny. Physiological and Biochemical Zoology 73(2): 200–208.

Assessing genetic diversity in the native Sydney rock oyster (Saccostrea glomerata) from the Sydney estuary, Australia Aroon R. Melwani, Macquarie University, Sydney, NSW Email: [email protected]

Genetic markers have been widely used to evaluate environmental impacts on aquatic populations. Many studies have shown that anthropogenic pollution can affect the population structure of marine invertebrates, through changes in genetic variation (Bickham et al. 2000, Moraga et al. 2002, Chung et al. 2011). Genetic changes include effects on fitness, decreased offspring, and physiological impacts (Belfiore and Anderson 2001). Populations from polluted environments may also exhibit reduced gene flow, shifts in age-classes, or reduced effect size, all of which may ultimately lead to changes in population composition (Bickham et al. 2000). The aim of my PhD study is to evaluate genetic diversity in the Sydney rock oyster (Saccostrea glomerata) from the Sydney estuary, Australia. The primary objective of this research is to examine whether oyster populations located in areas impacted by environmental contamination are genetically differentiated from populations in relatively non- impacted areas of the estuary. This work is part of the Sydney Institute of Marine Science’s Sydney Fig. 1. Aroon Melwani collecting DNA from an oyster Harbour Research Program ( http:// specimen in the field. Photo: K. Champ. harbourprogram.sims.org.au) and is being funded by my Thyne-Reid Doctoral Fellowship at the Sydney Institute of Marine Science. Genetic patterns in local populations of oysters from the Sydney estuary have not previously been investigated. This study addresses that deficit in our knowledge by studying the genetic diversity of Fig. 2. Gel image showing amplified DNA for a single Sydney rock oysters relative to local variability in microsatellite locus in the Sydney rock oyster. anthropogenic pollution. Locations in the estuary Photo: A. Melwani. were selected to encompass a range of water quality conditions ranging from sites that are heavily impacted by chemical contaminants (heavy metals, References PAHs, etc.) to relatively non-impacted areas. Genet- Belfiore, N.M. & Anderson, S.L. (2001). Effects of ic diversity will be assessed by polymerase chain re- contaminants on genetic patterns in aquatic action (PCR) using up to 10 microsatellite markers organisms: a review. Mutation Research 489, 97–122. Bickham, J.W., Sandhu S., Hebert P.D., Chikhi L. & Athwal R.. previously developed for S. glomerata. Each popula- (2000). Effects of chemical contaminants on genetic tion of oysters will then be evaluated by calculating diversity in natural populations: implications for several indicators of genetic variation. biomonitoring and ecotoxicology. Mutation Research This study represents the first genetic evalu- 463, 33–51. ation of S. glomerata to be undertaken in the Sydney Chung, P.P., Hyne, R.V. Mann, R.M. & Ballard J.W.O. (2011). Temporal and geographical genetic variation in the estuary. These data will allow me to determine amphipod Melita plumulosa (Crustacea: Melitidae): whether localized hotspots of contamination lead to Link of a localized change in haplotype frequencies to genetic differentiation of oyster populations, which a chemical spill. Chemosphere 82, 1050–1055. might be used as a marker of long-term environ- Moraga, D., Mdelgi-Lasram, E., Romdhane, M.S., Abed, A.E., Boutet, I., Tanguy A. & Auffret M. (2002). Genetic mental stress. This work will be used to contrast responses to metal contamination in two clams: other analyses that are underway in my PhD to iden- Ruditapes decussatus and Ruditapes philippinarum. Marine tify specific adaptive responses to environmental Environmental Research 54, 521–525. pollution in Sydney rock oysters.