The Darwin-Wallace Medal

Awarded to a person or group who have made major advances in evolutionary science.

Previously awarded to commemorate the 50th,100th and 150th anniversaries of the reading of the joint paper by Charles Darwin and Alfred Russel Wallace "On the Tendency of Species to form Varieties; and the Perpetuation of Varieties and Species by Natural Means of Selection", which was read on 1 July 1858, and published by the Linnean Society. In recognition of the continuing importance of research on evolutionary biology, the Council of the Society announced in 2008 that the medal would be awarded annually from 2010.

Eligibility Criteria:

  • Open to any scientist of any nationality, in the field of the understanding of evolution
  • For their major advances in evolutionary science and contribution to the wider natural history community, e.g. editorial and/or committee/policy work/public engagement
  • Nominee cannot, at the time of nomination, be a member of Council
  • Nominee does not need to be a Fellow of the Society
  • We do not accept self-nominations

Nominations should be submitted by completing the downloadable form and sending to by 30 November.


  • Sarah P Otto (2021)
  • Spencer Barrett (2020)
  • Svante Pääbo and David Reich (2019)
  • Josephine Pemberton (2018)
  • John Thompson (2017)
  • Pamela and Douglas Soltis (2016)
  • Roger Butlin (2015)
  • Dolph Schluter (2014)
  • Godfrey Hewitt (2013)
  • Loren Henry Rieseberg (2012)
  • James Lake (2011)
  • Brian Charlesworth (2010)
  • In 2009 the recipients of the Darwin-Wallace Medal were Nick Barton, M.W. Chase, Bryan Clarke, Joseph Felsenstein, Stephen Jay Gould (posthumously), Peter R. Grant, Rosemary Grant, James Mallet, Lynn Margulis, John Maynard Smith (posthumously), Mohamed Noor, H. Allen Orr, Linda Partridge
  • In 1958 the recipients of the Darwin-Wallace Medal were Edgar Anderson, Maurice Caullery, Ronal A. Fisher, C.R. Florin, J.B.S Haldane, Roger Heim, John Hutchinson, Julian Huxley, Ernst Mayr, H.J. Muller, E. Pavlovsky, Bernhard Rensch, G. Gaylor Simpson, Carl Skottsberg, E.A. Stensio, H. Hamshaw Thomas. G.V. Turesson, E. vn Straelen, D.M.S. Watson and J.C. Willis (posthumously).
  • In 1908 the recipients of the Darwin-Wallace Medal were in Gold; Alfred Russel Wallace and in Silver; Joseph D. Hooker, Ernst Haeckel, Eduard Strasburger, August Weisman, Francis Galton and E. Ray Lankester.

Sarah P Otto

Dr Sarah P. Otto, University of British Columbia, Darwin-Wallace Medal 2021

Sally Otto is a Canadian mathematical evolutionary biologist at the University of British Columbia. She is one of the major evolutionary theorists who have generated a new and much more focused synthesis of the debate about the evolution of sex and recombination, in spite of its known evolutionary costs. She has developed new models that show that genetic drift, even in rather large populations, can provide a major evolutionary impetus for the evolution of sex.

She has also focused attention on the evolution of polyploidy, leading to a landmark paper in 2000 that for the first time estimated the fraction of plant species that originate by polyploidy. Her iconic "saw-tooth" graph of the distribution of chromosome numbers recorded in plants demonstrated that species with even numbers of chromosomes tend to outnumber species with odd numbers due to recent speciation by chromosome doubling, something that hadn’t been obvious to generations of previous workers studying speciation and polyploidy. In her scientific articles, she writes with admirable clarity, rather uncommon among theoreticians, which makes even complex topics easy for her readers to understand.

She co-founded the Canadian Society for Ecology and Evolution and has served in leading roles in the Society for the Study of Evolution, the American Society of Naturalists and the European Society of Evolutionary Biology. She is also a passionate environmental advocate, serving on panels advising the Canadian government on climate change mitigation, and is a renowned advocate for biodiversity. She has been a strong supporter of equal opportunity action in science and has written a number of learned as well as popular articles specifically on this topic.

Professor Spencer Barrett

Professor Spencer Barrett, University of Toronto, Darwin-Wallace Medal 2020

Professor Barrett is one of the world’s leading authorities on the reproductive biology and genetics of flowering plants. Among his original findings is the first experimental demonstration of the selective purging of deleterious genes following inbreeding, the first genetic estimates of effective population size, and the most comprehensive evidence for the role of genetic drift in initiating adaptive changes in plant mating.

He also demonstrated, for the first time, that self-fertilisation has hidden costs because of lost mating opportunities through male fertility, a finding with profound implications for functional interpretation of plant reproductive traits. Professor Barrett provided the first experimental evidence in support of the Darwinian hypothesis for the adaptive significance of tristyly, and solved the long-standing puzzle of the evolution and function of mirror-image flowers.

These contributions have rejuvenated the field of reproductive biology making it one of the most active areas within ecology and evolutionary biology. In addition to his studies on plant reproduction, Professor Barrett is also an internationally recognised expert on the ecology and genetics of plant invasions and the environmental consequences of genetically modified crops. He has received numerous awards in recognition of his pre-eminence, and is one of the few Canadian biologists to be elected to both the Royal Society of Canada and the Royal Society of London. During his 31-year tenure at the University of Toronto, Professor Barrett has not only excelled as a scholar but also as an outstanding teacher, mentor and communicator of science.

Dr Josephine Pemberton
Dr Josephine Pemberton, Medal winner 2018
Dr John Thompson
Dr John Thompson, Medal winner 2017