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Jon Seger

Emeritus Professor

Ph.D. Harvard University


Office/Building: Biol 322
Phone: 801-581-4758
Email: seger@biology.utah.edu

Research Statement


Most mutations that strike genes and other adapted regions of a genome are expected to be deleterious because there are more ways to break a gene than to improve it. A strongly deleterious mutation causes little net harm because it is quickly eliminated by selection, but a weakly deleterious mutation may drift to high frequency or even fix, depending on the population's size, the strength of selection, and the indirect effects of selection at other sites in the mutation's genomic neighborhood. Thus large numbers of weakly deleterious mutations could circulate at intermediate frequencies, degrading fitness substantially. Together with some very talented colleagues and students, I have been studying this process in three ecologically connected groups of species: right whales (which have very small population sizes); the "whale lice" that live permanently on them (amphipod crustaceans in the family Cyamidae, with very large population sizes); and the favorite food of southern right whales (Antarctic krill, with truly astronomical population sizes).

Research Interests


General Interests
Specific Interests
  • Mitochondrial population genomics of whale lice (Amphipoda, Cyamidae)
  • Mildly deleterious mutations as obstacles to adaptation

Selected Publications


  • Johnson KP, Seger J (2001) Elevated rates of nonsynonymous substitution in island birds. Molecular Biology and Evolution 18:874-881.
  • Kaliszewska ZA, Seger J, Rowntree VJ, Barco SG, Benegas R, Best PB, Brown MW, Brownell RL Jr, Carribero A, Harcourt R, Knowlton AR, Marshall-Tilas K, Patenaude NJ, Rivarola M, Schaeff CM, Sironi M, Smith WA, Yamada TK (2005) Population histories of right whales (Cetacea: Eubalaena) inferred from mitochondrial sequence diversities and divergences of their whale lice (Amphipoda: Cyamus). Molecular Ecology 14:3439-3456, doi:10.1111/j.1365-294X.2005.02664.x.
  • Valenzuela LO, Sironi M, Rowntree VJ, Seger J. (2009) Isotopic and genetic evidence for culturally inherited site fidelity to feeding grounds in southern right whales (Eubalaena australis). Molecular Ecology 18:782-791, DOI: 10.1111/j.1365-294X.2008.04069.x
  • Seger J, Smith WA, Perry JJ, Hunn J, Kaliszewska ZA, La Sala L, Pozzi L, Rowntree VJ, Adler FR. (2010) Gene genealogies strongly distorted by weakly selected mutations in constant environments. Genetics 184:529-545. DOI: 10.1534/genetics.109.103556.
  • O'Fallon BD, Seger J, Adler FR. (2010) A continuous-state coalescent and the impact of weak selection on the structure of gene genealogies. Mol. Biol. Evol. 27(5):1162-1172. DOI:10.1093/molbev/msq006.
  • Kaltenpoth M, Showers Corneli P, Dunn DM, Weiss RB, Strohm E, Seger J (2012) Accelerated evolution of mitochondrial but not nuclear genomes of Hymenoptera: new evidence from crabronid wasps. PLoS ONE 7(3): e32826, doi:10.1371/journal.pone.0032826.
  • Rowntree VJ, Uhart MM, Sironi M, Chirife A, Di Martino M, La Sala L, Musmeci L, Mohamed N, Andrejuk J, McAloose D, Sala JE, Carribero A, Rally H, Franco M, Adler FR, Brownell RL Jr, Seger J, Rowles T (2013) Unexplained recurring high mortality of southern right whale Eubalaena australis calves at Península Valdés, Argentina. Marine Ecology Progress Series 493:275–289, doi:10.3354/meps10506.
  • Kaltenpoth M, Roeser-Mueller K, Koehler S, Peterson A, Nechitaylo T, Stubblefield JW, Herzner G, Seger J, Strohm E (2014) Partner choice and fidelity stabilize co-evolution in a Cretaceous-age defensive symbiosis. PNAS 111:6359-6364, doi:10.1073/pnas.1400457111.
  • Wilson C, Sastre AV, Hoffmeyer M, Rowntree VJ, Fire S, Santinelli NH, Díaz Ovejero S, D’Agostino V, Marón CF, Doucette GJ, Broadwater MH, Wang Z, Montoya N, Seger J, Adler FR, Sironi M, Uhart MM (2016) Southern right whale (Eubalaena australis) calf mortality at Península Valdés, Argentina: are harmful algal blooms to blame? Marine Mammal Science 32:423–451, doi:10.1111/mms.12263
  • Lewis-Rogers N, Seger J, Adler FR (2017) Human rhinovirus diversity and evolution: How strange the change from Major to minor. Journal of Virology 91(7): e01659-16. doi:10.1128/JVI.01659-16
  • Seger J, Rowntree VJ (2018) Whale lice. In Encyclopedia of Marine Mammals, Third Edition (ed B Würsig, JGM Thewissen, KM Kovacs), pp 1051-1054. Elsevier. ISBN: 978-0-12-804327-1
  • Valenzuela LO, Rowntree VJ, Sironi M, Seger J (2018) Stable isotopes (δ15N, δ13C, δ34S) in skin reveal diverse food sources used by southern right whales Eubalaena australis. Mar Ecol Prog Ser 603: 243-255, doi:10.3354/meps12722
  • Carroll EL, Alderman R, Bannister JL, Bérubé M, Best PB, Boren L, Baker CS, Constantine R, Findlay K, Harcourt R, Lemaire L, Palsbøll PJ, Patenaude NJ, Rowntree VJ, Seger J, Steel D, Valenzuela LO, Watson M, Gaggiotti OE (2019) Incorporating non-equilibrium dynamics into demographic history inferences of a migratory marine species. Heredity 122:53–68, doi:10.1038/s41437-018-0077-y
  • Carroll EL, Ott PH, McMillan LF, Galletti Vernazzani B, Neveceralova P, Vermeulen E, Gaggiotti OE, Andriolo A, Baker CS, Bamford C, Best P, Cabrera E, Calderan S, Chirife A, Fewster RM, Flores PAC, Frasier T, Freitas TRO, Groch K, Hulva P, Kennedy A, Leaper R, Leslie MS, Moore M, Oliveira L, Seger J, Stepien EN, Valenzuela LO, White B, Zerbini A, Jackson JA (2020) Genetic diversity and connectivity of southern right whales (Eubalaena australis) found in the Chile-Peru wintering ground and South Georgia/Islas Georgias del Sur feeding ground. J Heredity 111:263-276, doi:10.1093/jhered/esaa010
  • Agrelo M, Daura-Jorge FG, Rowntree VJ, Sironi M, Hammond PS, Ingram SN, Marón CF, Vilches FO, Seger J, Payne R, Simões-Lopes PC (2021) Ocean warming threatens southern right whale population recovery. Science Advances 7, eabh2823, 15 October 2021, doi:10.1126/sciadv.abh2823

Courses Taught


  • Biol 3410: Principles of Ecology and Evolution
  • Biol 3420: Evolutionary Biology
  • Biol 5221: Human Evolutionary Genetics
  • Biol 6092: Evolutionary Genetics and Genomics
  • Biol 2005: Biology of Variation