Congratulations to Dr Ceridwen Fraser – recipient of the International Biogeography Society’s 2019 MacArthur & Wilson Award!

Dr Fraser is an early-career biogeographer who has had a considerable impact on the field of biogeography.  Her highly innovative research on southern postglacial distribution shifts and geothermal glacial refugia has greatly expanded our understanding of how species distributions were influenced by past climate change in the Southern Hemisphere, and has highlighted key differences in Southern versus Northern Hemispere postglacial biogeographic changes.

Three key, inter-related areas to which Dr Fraser has made significant, innovative contributions include:

Postglacial distribution shifts in the Southern Hemisphere:

In the Northern Hemisphere, a great deal of research in recent decades has used molecular approaches to infer poleward or uphill distributional shifts for hundreds of taxa with postglacial warming. In contrast, until recently almost no comparable research had been conducted in the Southern Hemisphere, and how and where species had survived glacial periods in refugia, or how and which species had changed distributions, was poorly known. Dr Fraser’s work on passive dispersal of intertidal communities in the Southern Ocean has revealed striking signatures of postglacial recolonisation of many Southern Hemisphere shores since the Last Glacial Maximum (LGM). Importantly, she was able to use biological (phylogeographic) data to infer that existing models had drastically underestimated LGM Antarctic sea ice extent [9], and that oceanographic changes around Australia at the LGM affected species’ past distributions and contemporary biogeographic structure [10]. Her ground-breaking work on responses to past climate change in the Southern Hemisphere led her to be invited to write a review of postglacial trends for the prestigious journal Trends in Ecology and Evolution [21], where she highlighted key differences in responses, and challenges to movement, for Southern versus Northern Hemisphere organisms. Specifically, she showed that the Southern Ocean has apparently acted as a significant barrier to north-south movement for many species, whereas taxa in the less-oceanic Northern Hemisphere have been more able to achieve large latitudinal shifts with past climate change. Fraser has also contributed several other review papers on biological responses to climate change in the Southern Hemisphere [3, 22, 33, 34].

Long-distance dispersal:

Dr Fraser’s research on long-distance trans-oceanic dispersal in the Southern Hemisphere has ranged across diverse organisms and made several fascinating breakthroughs. For example, she made the first direct observation of a long-distance dispersal event by an entire community (diverse benthic invertebrates that had travelled across hundreds of kilometres of open ocean via rafting with buoyant macroalgae) [16], and has supervised research students testing the dispersal capacity of polychaete worms along Australian coasts [30] and penguin ticks around Australasia [32]. She has contributed to several key reviews of dispersal biogeography [4, 18, 23], including a major recent review of dispersal and connectivity of both marine and terrestrial taxa in the sub-Antarctic, led by one of her PhD students [39]. Recently, she has been investigating – in collaboration with the nominators and others – the critical role of density-dependent processes in restricting gene flow among populations despite ongoing dispersal [23, 29, 43]. This ‘founder takes all’ (aka ‘density- blocking’) process appears to underpin the distributions of many taxa and lineages globally, across a range of spatial scales, and helps to explain the endurance of signatures of long-past events (such as postglacial recolonisation) in phylogeographic patterns today. Dr Fraser has recently been awarded a prestigious, four-year Fellowship to determine the extent to which this process influences biogeographic patterns.

Geothermal glacial refugia:

How terrestrial species survived past ice ages in Antarctica has long puzzled scientists, with biological evidence indicating long term in situ survival, in apparent conflict with glaciological models of comprehensive ice coverage [21]. Fraser’s highly innovative hypothesis that volcanoes could have sheltered life through past ice ages in Antarctica has been supported by her empirical analyses demonstrating that biodiversity decreases with distance away from geothermal areas on the continent [27]. She has also used metabarcoding of soil from geothermal Antarctic caves to infer that diverse eukaryotes still inhabit subglacial geothermal environments in Antarctica [41]. The concept of geothermal refugia in Antarctica has now been widely accepted and has influenced diverse scientific and policy results (52 scientific papers have cited her 2014 PNAS paper on geothermal refugia; and the results fed into decisions to increase protection of geothermal areas in Antarctica at the 2014 meeting of the Scientific Committee of Antarctic Research).

Dr Fraser’s contributions have been both innovative and important to the field of biogeography, and we’re excited to present the MacArthur & Wilson Award to her at the upcoming 9th Biennial Conference of the International Biogeography Society.  Join us in hearing her plenary talk in Malaga, Spain – January 8-12, 2019!

Journal articles (peer-reviewed)

44. Moon KL, Chown SL, Loh S-M, Oskam CL & Fraser CI (in press). Australian penguin ticks screened for novel Borrelia species. Ticks and Tick-borne Diseases.

43. Fraser CI, Davies I, Bryant D & Waters JM (in press). How disturbance and dispersal influence intraspecific structure. Journal of Ecology. [doi: 10.1111/1365-2745.12900]

42. Blake C, Thiel M, López BA & Fraser CI (2017) Gall-forming protistan parasites infect southern bull-kelp across the Southern Ocean, with prevalence increasing to the south. Marine Ecology-Progress Series, 583:95-106. [doi: 10.3354/meps12346]

41. Fraser CI, Connell L, Lee CK & Cary SC (in press). Evidence of plant and animal communities at exposed and subglacial (cave) geothermal sites in Antarctica. Polar Biology. [doi: 10.1007/s00300-017-2198-9]

40. Waters JM, King TM, Fraser CI & Garden C (in press) Rafting dispersal in a brooding southern sea star (Asteroidea: Anasterias). Invertebrate Systematics.

39. Moon, KL, Chown SL & Fraser CI (2017). Reconsidering connectivity in the sub-Antarctic. Biological Reviews, 92:2164-2181. [doi: 10.1111/brv.12327]

38. Waters JM, Fraser CI, Maxwell JJ & Rawlence NJ (2017). Did interaction between human pressure and Little Ice Age drive biological turnover in New Zealand? Journal of Biogeography, 44:1481–1490. [doi: 10.1111/jbi.12991]

37. Weber XA, Edgar GJ, Banks SC, Waters JM & Fraser CI (2017). A morphological and phylogenetic investigation into divergence among sympatric Australian southern bull kelps (Durvillaea potatorum and D. amatheiae sp. nov.). Molecular Phylogenetics and Evolution, 107:630-643. [doi: 10.1016/j.ympev.2016.12.27]

36. Fraser CI, Kay GM, du Plessis M & Ryan, P (2017). Breaking down the barrier: dispersal across the Antarctic Polar Front. Ecography, 40:235-237. [doi: 10.1111/ecog.02449]

35. Fraser CI, McGaughran A, Chuah A & Waters JM (2016). The importance of replicating genomic analyses to verify phylogenetic signal for recently-evolved lineages. Molecular Ecology, 25:3683-3695. [doi: 10.1111/mec.13708]

34. Wilson LJ, Fulton CJ, Hogg A, Joyce K, Radford B & Fraser CI (2016). Climate-driven changes to ocean circulation and their inferred impacts on marine dispersal patterns and processes. Global Ecology and Biogeography, 25:923-939. [doi: 10.1111/geb.12456]

33. Chown SL, Clarke A, Fraser CI, Cary SC, Moon K & McGeoch MA (2015). The changing form of Antarctic biodiversity. Nature, 522:431-438. [doi:10.1038/nature14505]

32. Moon KL, Banks SC & Fraser CI (2015). Phylogeographic structure in penguin ticks across an ocean basin indicates allopatric divergence and rare trans-oceanic dispersal. PLoS One, 10(6): e0128514. [doi: 10.1371/journal.pone.0128514]

31. Muangmai N, Fraser CI & Zuccarello GC (2015). Contrasting patterns of population structure and demographic history in cryptic species of Bostrychia intricata (Rhodomelaceae, Rhodophyta) from New Zealand. Journal of Phycology, 51:574-585. [doi: 10.1111/jpy.12305]

30. Smith LM, Hutchings P & Fraser CI (2015). Molecular evidence supports coastal dispersal among estuaries for two benthic marine worm (Nephtyidae) species in southeastern Australia. Marine Biology, 162: 1319-1327. [doi: 10.1007/s00227-015-2671-31]

29. Fraser CI, Banks S & Waters JM (2015). Priority effects can lead to underestimation of dispersal and invasion potential. Biological Invasions, 17:1-8. [doi: 10.1007/s10530-014-0714-1]

28. Fraser CI, Brahy O, Mardulyn P, Dohet L, Mayer F & Gregoire J-C (2014). Flying the nest: male dispersal and multiple paternity enables extrafamilial matings for the invasive bark beetle Dendroctonus micans. Heredity, 113: 327-333. [doi: 10.1038/hdy.2014.34]

27. Fraser CI, Terauds A, Smellie J, Convey P & Chown SL (2014). Geothermal activity helps life survive glacial cycles. Proceedings of the National Academy of Sciences, USA, 111: 5634- 5639. [doi: 10.1073/pnas.1321437111]

26. Garden CJ, Currie K, Fraser CI & Waters JM (2014). Rafting dispersal constrained by an oceanographic boundary. Marine Ecology Progress Series, 501:297-302. [doi: 10.3354/meps10675]

25. Fraser CI, Zuccarello GC, Spencer HG, Salvatore LC, Garcia GR & Waters JM (2013). Genetic affinities between trans-oceanic populations of non-buoyant macroalgae in the high latitudes of the Southern Hemisphere. PLoS One, 8:e69138. [doi: 10.1371/journal.pone.0069138]

24. Fraser CI & Waters JM (2013) Algal parasite Herpodiscus durvillaeae inferred to have traversed the Pacific Ocean with its buoyant host. Journal of Phycology, 49:202-206. [doi: 10.1111/jpy.12017]

23. Waters JM, Fraser CI & Hewitt GM (2013) Founder takes all: density-dependent processes structure biodiversity. Trends in Ecology and Evolution, 28:78-85. [doi: 10.1016/j.tree.2012.08.024]

See also: Waters JM, Fraser CI, Banks SC & Hewitt GM (2013). The founder space race: a reply to Buckley et al. Trends in Ecology and Evolution, 28:190-191. [doi: 10.1016/j.tree.2013.01.008]

22. Fraser CI (2012) The impacts of past climate change on sub-Antarctic nearshore ecosystems. Papers and Proceedings of the Royal Society of Tasmania, 146:89-93.

21. Fraser CI, Nikula R, Ruzzante D & Waters JM (2012) Poleward bound: biological impacts of Southern Hemisphere glaciation. Trends in Ecology and Evolution, 27:462-471. [doi: 10.1016/j.tree.2012.04.011]

20. Fraser CI (2012) Is bull-kelp kelp? The role of common names in science. New Zealand Journal of Marine and Freshwater Research, 46:279-284. [doi: 10.1080/00288330.2011.621130]

19. Fraser CI, Spencer HG & Waters JM (2012) Durvillaea poha sp. nov. (Fucales, Phaeophyceae): a buoyant southern bull-kelp species endemic to New Zealand. Phycologia, 51:151–156. [doi: 10.2216/11-47.1]

18. Gillespie RG, Waters JW, Fraser CI, Nikula R, Baldwin BG & Roderick GK (2012) Long- distance dispersal – a framework for hypothesis testing. Trends in Ecology and Evolution, 27:47-55. [doi:10.1016/j.tree.2011.08.009]

17. Smith AM, Kregting L, Fern S & Fraser CI (2011) Sedimentology of a wreck: the Rainbow Warrior revisited. Marine Pollution Bulletin, 62:2412–2419. [doi:10.1016/j.marpolbul.2011.08.028]

16. Fraser CI, Nikula R & Waters JM (2011) Oceanic rafting of a coastal community. Proceedings of the Royal Society, B, 278:649-655. [doi: 10.1098/rspb.2010.1117]

15. Fraser CI, Winter DJ, Spencer HG & Waters JM (2010) Multigene phylogeny of the southern bull-kelp genus Durvillaea (Phaeophyceae: Fucales). Molecular Phylogenetics and Evolution, 57:1301–1311. [doi: 10.1016/j.ympev.2010.10.011]

14. Collins CJ, Fraser CI, Ashcroft A & Waters JM (2010) Asymmetric dispersal of southern bull- kelp (Durvillaea antarctica) adults in coastal New Zealand: testing an oceanographic hypothesis. Molecular Ecology, 19:4572–4580. [doi: 10.1111/j.1365-294X.2010.04842.x]

13. Smith AM, Wood ACL, Liddy MFA, Shears A & Fraser CI (2010) Human impacts in an urban port: the carbonate budget, Otago Harbour, New Zealand. Estuarine, Coastal & Shelf Science, 90:73-79 [doi:10.1016/j.ecss.2010.07.004]

12. Fraser CI, Thiel M, Spencer HG & Waters JM (2010) Contemporary habitat discontinuity and historic glacial ice drive genetic divergence in Chilean kelp. BMC Evolutionary Biology, 10:203 [doi:10.1186/1471-2148-10-203]

11. Nikula R, Fraser CI, Spencer HG, Waters JM (2010) Circumpolar dispersal by rafting in two subantarctic kelp-dwelling crustaceans. Marine Ecology-Progress Series, 405:221-230 [doi: 10.3354/meps08523]

10. Fraser CI, Spencer HG & Waters JM (2009) Glacial oceanographic contrasts explain phylogeography of Australian bull kelp. Molecular Ecology, 18:2287–2296 [doi: 10.1111/j.1365- 294X.2009.04201.x]

9. Fraser CI, Nikula R, Spencer HG & Waters JM (2009) Kelp genes reveal effects of subantarctic sea ice during the Last Glacial Maximum. Proceedings of the National Academy of Sciences, USA, 106:3249-3253 [doi: 10.1073/pnas.0810635106]

8. Fraser CI, Hay CH, Spencer HG & Waters JM (2009) Genetic and morphological analyses of the southern bull kelp Durvillaea antarctica (Phaeophyceae: Durvillaeales) in New Zealand reveal cryptic species. Journal of Phycology, 45: 436-443 [doi: 10.1111/j.1529-8817.2009.00658.x]

7. Fraser C, Hutchings PA & Williamson JE (2006) Long-term changes in polychaete assemblages of Botany Bay (NSW, Australia) following a dredging event. Marine Pollution Bulletin, 52(9): 997-1010 [doi:10.1016/j.marpolbul.2005.12.016]

6. Fraser C, Capa M & Schuchert P (2006) European hydromedusa Eleutheria dichotoma (Anthomedusae: Cladonematidae) found at high densities in New South Wales, Australia: distribution, biology and habitat. Journal of the Marine Biological Association of the United Kingdom, 86: 699-703 [doi:10.1017/S0025315406013592]

Book chapters (peer-reviewed)

5. Convey P, Bowman VC, Chown SL, Francis JE, Fraser CI, Smellie JL, Storey B, Terauds A (in press). Ice-bound Antarctica: biotic consequences of the shift from a temperate to a polar climate. In: Mountains, Climate and Biodiversity (Ed.s Hoorn C, Perrigo A and Antonelli A). Wiley: Amsterdam.

4. Thiel M & Fraser CI (2016). The role of floating plants in dispersal of biota across habitats and ecosystems. In: Marine Macrophytes as Foundation Species (Ed. Olafsson E). CRC Press: Boca Raton. pp 76-99.

3. Fraser CI (2016). Change in Southern Hemisphere intertidal communities through climate cycles: the role of dispersing algae. In: Seaweed Phylogeography: Adaptation and Evolution of Seaweeds under Environmental Change. (Ed.s Zi-Min H and Fraser C). Springer: Beijing. pp 131-143.

2. Wilson LJ, Weber XA, King TM & Fraser CI (2016). DNA extraction techniques for genomic analyses of macroalgae. In: Seaweed Phylogeography: Adaptation and Evolution of Seaweeds under Environmental Change. (Ed.s Zi-Min H and Fraser C). Springer: Beijing. pp 363-386.

Encyclopaedia entry (peer-reviewed)

1. Waters JM & Fraser CI (2016). Dispersal biogeography. In: Encyclopaedia of Evolutionary Biology. (Ed. in Chief: Richard Kliman). Academic Press: Oxford. pp 453-457. [Book release date: May 2016. 2232 pp. ISBN 9780128000496]

Popular science articles (not peer reviewed)

Fraser, C (2017) Fair winds and following seas: yes, a spider could migrate across an ocean. The Conversation, 3 August 2017. [read more than 3,500 times]

Fraser, C (2016) Antarctica may not be as isolated as we thought, and that’s a worry. The Conversation, 27 May 2016. [read more than 44,000 times]

Fraser, C (2014) Volcanoes shelter life through Ice Ages. Australasian Science, July/August edition.

Fraser, C (2014) Antarctic volcanoes help preserve life in the freezer. The Conversation, 11 March 2014. [read more than 2,400 times]

Fraser, C (2009) An icier Ice Age. Australasian Science, June 2009

Fraser, C, Capa, M and Schuchert, P (2006) These arms are made for walking: tiny ‘walking jellyfish’ patrol intertidal algae. JMBA Global Marine Environment, 4:6-7*