Paul Bentzen

esearch in my laboratory focuses on the population, evolutionary and conservation genetics of fishes and marine organisms. I am interested in how genetic variation is distributed within and among populations, how historical and ongoing processes have shaped the patterns of genetic variation that exist today, and what contemporary patterns of genetic variation can tell us about the history, ecology, evolutionary attributes and conservation status of populations.

Examples of past processes that influence contemporary genetic variation include previous ice ages that forced fishes into refugia where they evolved in isolation for periods of time, and much more recent human-related impacts that have drastically reduced the abundance of some species and populations.

Ongoing processes include environmental and biological factors that influence the extent to which organisms disperse or migrate from one area to another, and natural selection, which governs how organisms are adapted to particular environments. My students and I examine these factors and try to determine how they all mesh together by surveying genetic variation across populations using a variety of molecular techniques.

Recently, these techniques have begun to include next-generation DNA sequencing and ‘genomic’ analyses that are yielding far more data than was imaginable just a few years ago. One result is that we are learning much more about the pattern and extent of adaptive genetic variation in fish genomes.

My students and I also have broad interests in the use of molecular methods to answer questions about the ecology and reproductive biology of organisms. Studies in this category use microsatellites to investigate kinship among individuals within populations, and particularly, which individuals are the offspring of which other individuals.

I also serve as director of the Marine Gene Probe Laboratory, a multi-user laboratory situated in the Department of Biology and dedicated to the application of molecular genetic methods to a variety of biological sub-disciplines, including ecology, evolution, conservation and resource biology.

Examples of Students' Research Topics

Honors BSc Students

• Xiaozhu “Sean” Chuan – Population genetics of threespine sticklebacks
• Beth Watson – Pedigree analysis of experimental Trinidadian guppy populations
• Jordan Gardiner – Copy number variation in MHC genes in Trinidadian guppies
• Gordon Byron – Phylogenetic analysis of nudibranchs and endosymbiont zoxanthellae
  
  

Graduate Students

• Mark Coulson, PhD 2014. Phylogeography, population structure and morphological adaptations among populations of anadromous rainbow smelt (Osmerus mordax).
• Meghan McBride MSc 2013. Defining the population structure and spatial distribution of the Alewife (Alosa pseudoharengus) in the Maritime Provinces and Maine.
• Lyndsey Baillie, MSc 2012. Population structure and genetic response to the parasite Gyrodactylus in the Trinidadian guppy (Poecilia reticulata).
• Adam Cook, PhD 2012.  Genotypic variation and phenotypic expression of Nova Scotia coregonids.
• Craig Reynolds, MSc 2011. The effect of acidification on the survival of American eel (Anguilla rostrata).
• Dan Hasselman, PhD 2010. Influence of historical contingency and contemporary microevolutionary processes on genetic structure of an anadromous fish.
• Megan McCusker, PhD 2009. The demographic history and population structure of three species of wolffishes across the North Atlantic Ocean.
• Ian Bradbury, PhD, 2007. Dispersal, homing, and connectivity in the estuarine fish, Osmerus mordax.
• Kim Murray, MSc 2005. Population genetic assessment of the endangered Atlantic Whitefish, Coregonus huntsmani, and the Lake Whitefish, C. clupeaformis, in Atlantic Canada.
• Jack Lighten, PhD (in progress). MHC polymorphism in Trinidadian guppies.
• Stanley King, PhD (in progress). The evolution of biodiversity in gyrodactylid parasites: characterizing genetic variation across spatial and temporal scales.
• Christine Angelidis, MSc (in progress). Role of MHC polymorphism in mate choice and local adaptation in Trinidadian guppies.
• Marion Sinclair-Waters, MSc (in progress). Population genomics of Atlantic cod.

Beach seining juvenile smelt and striped bass for genetic analysis

Some Graduates' Occupations

• Research Scientist, Fisheries and Oceans Canada
• Biologist, Fisheries and Oceans Canada
• Research Scientist, United States Geological Service, Biological Resources Division, Anchorage, Alaska
• Research Scientist, National Marine Mammal Laboratory, Seattle.
• Research Scientist, National Marine Fisheries Service, Seattle
• Forensic Biologist, National Marine Fisheries Service, Seattle
• Post-doctoral Fellow, Canadian universities
• Laboratory Manager, Stanley Center for Psychiatric Research
  
  

Selected Publications

Bradbury, IR, S Bowman, T Borza, PVR Snelgrove, JA Hutchings, PR Berg, N Rodriguez-Expeleta, J Lighten, DE Ruzzante, C Taggart, P Bentzen. 2014. Long distance linkage disequilibrium and limited hybridization suggest cryptic speciation in Atlantic cod.  PLOS ONE. 9(9): e106380. doi:10.1371/journal.pone.0106380

McBride, MC, TV Willis, RG Bradford, P Bentzen. 2014. Genetic diversity and structure of two hybridizing anadromous fishes (Alosa pseudoharengus, Alosa aestivalis) across the northern portion of their range. Conservation Genetics DOI 10.1007/s10592-014-0617-9

Lighten, J, C van Oosterhout, IG Paterson, M McMullan, P Bentzen. 2014. Ultra-deep Illumina sequencing accurately identifies MHC class IIb alleles and provides evidence for copy number variation in the guppy (Poecilia reticulata). Molecular Ecology Resources doi: 10.1111/1755-0998.12225

Lopez-Sepulcre, A, S Gordon, I Paterson, P Bentzen, D Reznick. 2013. Beyond lifetime reproductive success. The posthumous reproductive dynamics of male Trinidadian guppies. Proceedings of the Royal Society, Series B. 280: 20131116. http://dx.doi.org/10.1098/rspb.2013.1116

Hasselman, DJ, D Ricard and P. Bentzen. 2013. Genetic diversity and differentiation in a wide ranging anadromous fish, American shad (Alosa sapidissima), is correlated with latitude. Molecular Ecology doi: 10.1111/mec.12197

McCusker, MR, D Denti, L Van Guelpen, E Kenchington and P Bentzen. 2012. Barcoding Atlantic Canada’s commonly encountered marine fishes. Molecular Ecology Resources doi: 10.1111/1755-0998.12043

Jensen, PC and P Bentzen. 2012. A molecular dissection of the mating system of the Dungeness Crab, Metacarcinus magister (Brachyura: Cancridae). Journal of Crustacean Biology 32(3):443-456

Bradbury, IR, MW Coulson, SE Campana, IG Paterson and P Bentzen. 2011. Contemporary nuclear and mitochondrial DNA clines in a north temperate estuarine fish reflect Pleistocene vicariance. Marine Ecology Progress Series 438: 207–218.

Coulson, MW, D Denti, L Van Guelpen, C Miri, E Kenchington and P Bentzen. 2011. DNA barcoding of Canada’s skates. Molecular Ecology Resources doi: 10.1111/j.1755-0998.2011.03034.x

McCusker, MR and P Bentzen. 2010. Historical influences dominate the population genetic structure of a sedentary marine fish, Atlantic wolffish (Anarhichas lupus), across the North Atlantic Ocean. Molecular Ecology 19(19):4228-4241.

Bradbury IR, S Hubert, B Higgins, T Borza, S Bowman, IG Paterson, PVR Snelgrove, C Morris, R Gregory, DC Hardie, JA Hutchings, D Ruzzante, C Taggart and P Bentzen. 2010. Parallel adaptive evolution of Atlantic cod on both sides of the Atlantic Ocean in response to temperature. Proceedings of the Royal Society, Series B published online 30; June 2010 doi: 10.1098/rspb.2010.0985

McCusker, MR and P Bentzen. 2010. Positive relationships between genetic diversity and abundance in fishes. Molecular Ecology doi: 10.1111/j.1365-294X.2010.04822.x.

Bradbury, IR, MW Coulson, A Cook and P Bentzen. 2010. Evidence for divergence and adaptive isolation in post-glacially derived bimodal allopatric and sympatric rainbow smelt populations. Biological Journal of the Linnean Society. 101:583-594.

Hasselman, DJ, RG Bradford and P Bentzen. 2010. Taking stock:  Defining populations of American shad (Alosa sapidissima) in Canada using neutral genetic markers. Canadian Journal of Fisheries and Aquatic Sciences. 67:1021-1039.

Bradbury, IR, SE Campana and P Bentzen. 2008. Otolith elemental composition and adult tagging reveal spawning site fidelity and estuarine dependency in rainbow smelt. Marine Ecology Progress Series doi: 10.3354/meps07583

Bradbury, IR, SE Campana, and P Bentzen. 2008. Low genetic connectivity in an estuarine fish with pelagic larvae. Canadian Journal of Fisheries and Aquatic Sciences. 65:147-158.

Spies, IB, EC Anderson, K Naish, and P Bentzen. 2007. Microsatellite markers clarify the origin and population structure of Oncorhynchus nerka in the Lake Washington watershed, Washington State, USA. Canadian Journal of Fisheries and Aquatic Sciences 64:1209-1221.

Bradbury, IR and P Bentzen. 2007. Dispersal, life history, and non-linear genetic isolation by distance. Marine Ecology Progress Series 340:255-257.

O’Reilly, PT, MF Canino, KM Bailey and P Bentzen. 2004. Inverse relationship between FST and microsatellite polymorphism in the marine fish, walleye pollock (Theragra chalcogramma): implications for resolving weak population structure. Molecular Ecology 13:1799-1814.

Canino, MF and P Bentzen. 2004. Evidence for positive selection at the pantophysin (Pan I) locus in walleye pollock, Theragra chalcogramma. Molecular Biology and Evolution 21(7):1391-1400.

Larson, S, R Jameson, M Etnier, M Fleming and P Bentzen. 2002. Loss of Genetic Diversity in Sea Otters (Enhydra lutris) Associated with the Fur Trade of the 18th and 19th Centuries. Molecular Ecology. 11:1899-1904

Bentzen, P, JB Olsen, JE McLean, TR Seamons and TP Quinn. 2001. Kinship analysis of Pacific salmon: insights into mating, homing, and timing of reproduction. Journal of Heredity 92:127-136.

Hendry, AP, JK Wenburg, P Bentzen, EC Volk, TP Quinn. 2000. Rapid evolution of reproductive isolation in the wild: evidence from introduced salmon. Science 290:516-518.

Bentzen, P, JM Wright, L Bryden, M Sargent, and KCT Zwanenburg.  1998.  Shared pattern of tandem repeat polymorphism and heteroplasmy in the mitochondrial control region of redfishes (Sebastes: Scorpaenidae). Journal of Heredity 89:1-7.

Bentzen, P, CT Taggart, DE Ruzzante, and D Cook.  1996.  Microsatellite polymorphism and the population structure of Atlantic cod (Gadus morhua) in the northwest Atlantic. Can. J. Fish. Aquat. Sci. 53:2706-2721.

Links

• Bentzen Laboratory
• Marine Gene Probe Laboratory
• http://www.dal.ca/academics/programs/undergraduate/marinebio.html