Sarah Adamowicz

photo of Sarah Adamowicz
Assistant Professor
Phone number: 
519-824-4120 x53055
Centre for Biodiversity Genomics (CBG) Rm. 113
Biodiversity Institute of Ontario, Rm. 1012


I am interested in the diversity of life: How many species are there? Why are some groups of organisms so much more diverse than others? How do environmental and biological traits influence speciation rate and rates of molecular evolution? Are there large-scale patterns in the history of life? My work involves combining DNA sequence data, organismal traits, information from the fossil record, and comparative analytical methods (the macroevolutionary analog of human twin studies) to address these questions. I additionally contribute to the Barcode of Life campaign and am developing approaches for using these vast DNA sequence resources for broad exploratory and hypothesis-driven biodiversity science. I have a particular focus on aquatic invertebrates and biodiversity of the arctic.


  • B.Sc. – Dalhousie University (1998)
  • M.Sc. – University of Guelph (2002)
  • Ph.D. – Imperial College London (2006)
  • Postdoc – University of Waterloo (2008)


The Shape of the Tree of Life

All organisms on earth are inter-related, and this fact is often represented using the Tree of Life metaphor. I aim to understand the relationships amongst species and the factors that influence the shape of this tree. Why is it that some branches are so much more species rich than others? This work involves analyzing DNA sequence data to explore species relationships, followed by analyses to investigate the factors that influence speciation rate. One current project is a collaborative investigation of relationships and evolutionary rates within the diverse endemic amphipod crustaceans of Lake Titicaca in Bolivia and Peru.

Major Transitions in Evolution

Major transitions in evolution—such as the transition from aquatic to terrestrial life or the evolution of flight—have had vital impacts upon the distribution and very nature of biodiversity on our planet. I am interested in better understanding the frequency of such transitions and the rate at which reversals occur, as well as the consequences of such transitions for molecular evolutionary patterns and speciation rates. One ongoing investigation is testing the influence of important biological transitions (e.g. shifts among larval types and developmental modes) on rates of speciation and molecular evolution in invertebrates inhabiting the ancient lakes of the world.

Evolutionary Trends

I am also interested in the question of whether there are large-scale patterns in the history of life. Arthropods, being the most diverse animal phylum and possessing a modular body plan, are proving to be an excellent model group in which to investigate whether repeated evolutionary trajectories have occurred. I am pursuing research on the degree of segmentation in arthropods and patterns in the evolution of their limb structure. This line of research is providing new insights into the degree of contingency vs. predictability during evolution.

The Diversity and Integrity of Freshwater Ecosystems

How many species are there on Earth? This seemingly simple question has been posed many times but we still have only a rough estimation that there are likely between 10 and 100 million species. I am interested in answering this question more clearly for freshwater invertebrates, using molecular, ecological, and taxonomic methods to study the diversity, distributions, traits, and origins of species. I also aim to understand what kinds of species live together within defined ecosystems and what kinds of communities are resistant to invasive species.

The Diversity of Polar Life

Arctic life is experiencing great threats due to climate change as well as increased development and shipping. However, monitoring and managing arctic biodiversity is compromised by the fact that we do not even know how many species inhabit these regions, despite the modest biodiversity that is present. Using DNA barcoding, I aim to discover the true extent of arctic species diversity and to understand the geographical distributions and origins of arctic species. This work involves focused field collections and analysis of biodiversity at the sub-arctic site of Churchill, Manitoba, in combination with collaborative projects at other localities throughout the circumarctic region. I am also interested in the types of adaptations that organisms have undergone to be able to survive in polar conditions, and in learning to predict what kinds of southerly organisms are likely to invade or become problematic in the north during the course of climate change.

Select Publications

  • Adamowicz, S.J., Colbourne, J.K., Witt, J.D.S., and Hebert, P.D.N. 2009. The scale of divergence: a phylogenetic appraisal of intercontinental allopatric speciation in a passively dispersed zooplankton genus. Molecular Phylogenetics and Evolution, 50: 423-436.
  • Adamowicz, S.J., Purvis, A., and Wills, M.A. Increasing morphological complexity in multiple parallel lineages of the Crustacea. Proceedings of the National Academy of Sciences of the USA, 105: 4786-4791.
  • Rowe, C.L., Adamowicz, S.J., and Hebert, P.D.N. (2007) Three new cryptic species of the freshwater zooplankton genus Holopedium (Crustacea: Branchiopoda: Ctenopoda), revealed by genetic methods. Zootaxa 1656: 1-49.
  • Adamowicz, S.J., Menu-Marque, S., Hebert, P.D.N., and Purvis, A. (2007) Molecular systematics and patterns of morphological evolution in the Centropagidae (Copepoda: Calanoida) of Argentina. Biological Journal of the Linnean Society 90: 279-292.
  • Dooh, R.T., Adamowicz, S.J., and Hebert, P.D.N. (2006) Comparative phylogeography of two North American glacial relict crustaceans. Molecular Ecology 15: 4459-4475.
  • Adamowicz, S.J., and Purvis, A. (2006) From more to fewer? Testing an allegedly pervasive trend in the evolution of morphological structure. Evolution 60: 1402-1416.
  • Adamowicz, S.J., and Sacherov, V. (2006) Testing the directionality of evolution: the case of chydorid crustaceans. Journal of Evolutionary Biology 19: 1517-1530.
  • Adamowicz, S.J., and Purvis, A. (2005) How many branchiopod crustacean species are there? Quantifying the components of underestimation. Global Ecology and Biogeography 14: 455-468.
  • Adamowicz, S.J., Hebert, P.D.N., and Marinone, M.C. (2004) Species diversity and endemism in the Daphnia of Argentina: a genetic investigation. Zoological Journal of the Linnean Society 140: 171-205.
  • Adamowicz, S.J., Gregory, T.R., Marinone, M.C., and Hebert, P.D.N. (2002) New insights into the distribution of polyploid Daphnia: the Holarctic revisited and Argentina explored. Molecular Ecology 11: 1209-1217.


  • BIOL*4610 Arctic Ecology (with Hebert)

Graduate Students

  • Michelle Pyle (MSc)
  • Tzitziki Loeza-Quintana (PhD)
  • T. Fatima Mitterboeck (PhD)
  • Robert Young (PhD)