ISSN 1188-603X

No. 452 April 11, 2012 Victoria, B.C.
Dr. A. Ceska, P.O.Box 8546, Victoria, B.C. Canada V8W 3S2


From: Jacques Cayouette, translated by Hugues Massicotte and Linda Tackaberry [Originally published in CBA/ABC Bulletin 45(1): 20-22. Posted in BEN with permissions.]

The internationally renowned Quebec ecologist, Pierre Dansereau, died in Montreal on September 28, 2011, at age 99, a week before reaching his 100th birthday. His centenarian wife, the painter Françoise Masson, survives him, as well as his younger brother Michel, who gave a brilliant testimony at the funeral.

Following his death, many written accounts have been published in newspapers and electronic media, documents still accessible on the Web. Everyone provided testimonies as expert, friend, colleague, student, former employee, director, dean, journalist. These include descriptive accounts and judgments of this distinguished personage and his career. It is difficult to summarize and assess these since many were written on the spur of the moment and one should, perhaps, wait a while to reconsider them later, more objectively.

Because of his longevity and the many facets of his varied career, we may possibly have to wait until the publication of his critical biography. Indeed, how can one sum up the life of a nearly century-old man who has taught in twenty universities on five continents, received more than fifteen honorary degrees, sixty decorations and merits from various governments and learned societies, published more than 600 scientific works including nearly a dozen books, and directed over fifty graduate students? Already in 1957, when Pierre Dansereau had been elected president of the Geographical Society of Montreal, the geographer Camille Laverdière, who was to welcome the new president, was finding the task of summarizing his career very difficult. Pierre Dansereau is not alone in this situation; we still await a critical biography of Marie-Victorin as a botanist, as well as those of Fernald, Stebbins and Cronquist, people often considered to be larger than life.

However, one can still sketch the main lines of the path taken by Pierre Dansereau, botanist, ecologist, biogeographer, ecosociologist, educator, ethicist, humanist, scholar and philosopher, and to emphasize the work done in Quebec and elsewhere in Canada. The following summary of his biography is based on an account written by a person close to him, the sociologist Jean-Guy Vaillancourt, published at the end of the first part of the unfinished autobiography of Pierre Dansereau: La lancée, 1911-1936. Autobiographie. Éditions Multimondes. 2005. (Vaillancourt: Biographie, pp. 133-137).

Pierre Dansereau was born in Outremont, Montreal, in 1911. He attended the Jesuit Collèges of Sainte-Marie (Montreal) and Sacré-Cœur (Sudbury). After earning his BA in 1932 at the University of Montreal, he studied three years at l'Institut Agricole d'Oka, from which he emerged with training in agricultural sciences. He discovered an interest in botany, thanks to the dynamic teachings of Father Louis-Marie, a Trappist, botanist and author of Flore-Manuel de la Province de Québec (1931). During his vacation in Percé, Gaspé, he applied his knowledge of the flora. His first observations relate to the phenology of death camas (Zigadenus glaucus, now Anticlea elegans, 1934) and he is the first to comment on Erigeron compositus (1937), an arctic-alpine disjunct species still rare in Gaspésie.

After a term at the University of Paris, he began a Doctorate in Sciences in Geneva (Switzerland) which he completed in 1939 under the direction of B.P.G. Hochreutiner. He studied the Mediterranean genus Cistus and integrated into his work other aspects such as plant collecting campaigns, methods for massive collections, systematics, cytology and hybrid studies. At the same time, he did an apprenticeship in phytosociology in Montpellier (France) at the Station Internationale de Géobotanique Méditerranéenne et Alpine (SIGMA) when Josias Braun-Blanquet was the director.

Upon his return to Montreal, from 1940 to 1942, he began work with Brother Marie-Victorin at the Montreal Botanical Garden, while keeping a close association with Jacques Rousseau. These two luminaries are among his early mentors. Between 1940-1950, as a lecturer, he taught ecology at the University of Montreal, a first for this discipline, and botanical taxonomy at Macdonald College, McGill University. His expertise in agronomy and phytosociology enabled him to do pioneering work in agriculture, pastures (1947-9), parasites (1957) and weeds in Quebec (1947-8). During this period, he headed the Service of Biogeography in the Province of Quebec. He studied among others the ecology of peatlands (1952) and his work on the Laurentian maple groves attracts attention (1943-46). He described the nature and characteristics of the sugar maple ecosystem to its limit in the Gaspé area (1944). He is concerned about the future of the sugar maple industry (1945) and conducted research on the geography and ecology of yellow birch (Betula alleghaniensis) (1959, 1966), the introgression between sugar maple (Acer saccharum) and black maple (Acer nigrum) (1941, 1947), and the complex of yellow violets (Viola pubescens) (1957, 1966). He was also interested in the classification of aquatic vegetation in the axis of the Great Lakes-St. Lawrence (1945, 1959). With Doris Löve, then at the University of Montreal, he studied the genus Xanthium (1959) and later with another team, the genus Alchemilla (1964).

Through the Arctic Institute of North America, he participated, in the early 1950s, to the Baird expedition on Baffin Island. He conducts, among others, studies on arctic Potentilla, a species that still causes problems for taxonomists. His observations on growth patterns of species of Potentilla nivea complex and Potentilla vahliana (1954-1956) continue to be very useful today. In terms of botanical history, he joins others in his entourage who pay homage to Marie-Victorin (1945) and presents his own synthesis of those who have influenced the botanical tradition in Montreal (1956).

He participated in organizing botanical excursions in the Gaspésie, Montreal area and Montérégie during international botanical congresses in Montreal: Botanical Society of America (1947) and IX International Botanical Congress (1959). Later in 1970, during a joint meeting of the CBA/ABC and the Canadian Society of Plant Physiology at l'Université Laval, Quebec, he directed most trips taking place in the Gaspésie vicinity.

Natural sciences remained his bread and butter, and research on forest dynamics consolidated his reputation. His work led him to develop a system that describes vegetation structure from a spatial perspective, which allowed him to further compare systems worldwide. During this time, he was influenced by numerous concurrent personages, in particular the Americans Emma Lucy Braun, Henry S. Conard and Stanley A. Cain. Unable to find a full-time position at any Quebec university, he goes to the United States and teaches at the University of Michigan, Ann Arbor, from 1950 to 1955. Back in Montreal from 1955 to 1961, he headed the "Institut Botanique" and became dean of the Faculty of Science, University of Montreal. However, never feeling comfortable in administrative positions, and also because of his progressive ideas and outspoken approach, he returned to the United States. He then taught at Columbia University and also became deputy director and head of the department of ecology of the New York Botanical Garden.

It was during this period that he published his famous Biogeography, an Ecological Perspective (1957). His ideas in ecology had evolved and he becomes the first to incorporate concepts of urban and human ecology, which would be his trademark until the end of his career. This seminal publication seems to bridge between the first stage of his career, when the natural sciences dominated via the taxonomy, plant ecology, biosystematics and biogeography, and the second stage that is devoted to sociology.

According to Jean-Guy Vaillancourt, the second stage of Pierre Dansereau's career is more focused on social sciences, through human ecology, ecodevelopment, environmental sociology and ecosociology. In this new domain, he is influenced by many, including the biologist and environmentalist, Rachel Carson, and the philosopher, theologian, and paleontologist, Jesuit Pierre Teilhard de Chardin. He is interested not so much in the influence of nature on humans, but rather the human impact on nature through agriculture, urbanization and industrialization. He believed that any ecological approach must be multidisciplinary and have ecodevelopment as an objective. This concept was akin to sustainable development. In the late 1960s, he returned to the University of Montreal to teach in the Urban Institute (1968-1971), and, starting in 1971, at the Université du Québec à Montréal (UQAM). He appreciated the openness of this young institution where the "walls between departments" were not as rigid as elsewhere.

During that time, he led a major project, a public interest enquiry called Étude écologique de la zone du futur aéroport international de Montréal (EZAIM) (1971 onwards). He teamed up with geographers, geologists, biologists, engineers and even a social psychiatrist, and produced a dozen innovative reports. The political context being what it was, of which Pierre Dansereau was keenly aware, meant that many decisions had already been taken. Nevertheless, it was an opportunity for him to implement his ideas of integrating nature and humanity. He suggested replacing the pattern of the classic food chain pyramid, by that of a sphere with arrows pointing in all directions, his famous "ball-of-arrows" in six trophic levels: minerotrophic, phytotrophic, herbivore zootrophic, carnivore zootrophic, investment and control.

He continued his work at UQAM where he was named professor emeritus in 1989. He directed the Laboratory for the study of ecosystems and land use planning until the age of 94. During this period, the values of humanism and ethics that have followed him throughout his career, took precedence over those of scientific research. In addition to directing theses, he presents his classes, lectures and writings to a wider and more diverse audience. His wisdom, his philosophical ideas and expertise are sought at various advisory levels. He signed the prefaces of many books on nature and geography published in Quebec, including the foreword of the third edition of the Flore Laurentienne (1995), first produced in 1935 by one of his mentors, Marie-Victorin. Meanwhile, his faithful secretary during 48 years, Virginia Weadock, continued to support him tirelessly. An eternal optimist, he proposes the concept of "joyful austerity", the idea of living well with less. One of his last speeches made in 2006 witnessed his opposition to privatization by the Quebec Government of the park, Mount Orford, in the Eastern Townships.

Among the many foreign countries that hosted him, Brazil was, undoubtedly, his second home. He made several field studies in tropical forest and offered regular teaching. He was kindly nicknamed Pedro della Silva. In 1998, he was given a glowing tribute, two-day symposium on his life and career. The result was a 700 page publication including the highlights of his intellectual legacy, testimonials from people, and the most complete bibliography published to date: Ecologia Humana, Ética e educação. A mensagem de Pierre Dansereau (1999), produced by Paulo Freire Vieira and Andrés Mauricio Ribeiro. Have we missed the boat here by not giving him a similar tribute, or even to go further?

Thus, in this bibliography, we find the principal works of his career highlights, in addition to those already cited: Biogeography (1957) and his autobiography (2005). Among these are: Phytogeographica Laurentiana. II. The principal plant associations of the Saint Lawrence Valley (1959), Contradictions & biculture (1964), Dimensions of environmental quality (1971), La Terre des hommes et le paysage intérieur (1973), Inscape and Landscape (1973, 1975), The human perception of environment (1975), Harmony and Disorder in the Canadian Environment (1975), Harmonie et désordre dans l'environnement canadien (1980), Essai de classification et de cartographie écologique des espaces (1985), L'envers et l'endroit: le désir, le besoin et la capacité (1991, 1994).

He has contributed to various encyclopedic works where he established the definition of his scientific domain. Noteworthy are contributions to the Encyclopedia Americana, Encyclopaedia Universalis, Encyclopedia McGraw-Hill of Science and Technology, The Canadian Encyclopedia / L'Encyclopédie du Canada, and their various editions.

Pierre Dansereau was much sought after by the media and he gracefully volunteered his time to them. In 1981, journalist Therese Dumesnil made several interviews with him and published Pierre Dansereau, l'écologiste aux pieds nus. Editions Nouvelle Optique. In 2001, his cousin, the filmmaker, Fernand Dansereau, made a wonderful documentary about his exceptional career: An Ecology of Hope (National Film Board): In 2002, Productions Impex, directed by André Larochelle, produced a documentary A Man for the Whole World giving another version of Dansereau's scientific career: In recent years, the Archives Department at UQAM has made available a virtual exhibition of Pierre Dansereau:

While the Encyclopedia Britannica describes him as a founder of contemporary ecology and although his reputation spread over several continents, Pierre Dansereau has always remained a very friendly person, known for his accessibility, his kindness, his charm, his empathy, and his magnetism, as rightly pointed out by his assistant of the past two decades, the cartographer Daniel Garneau, from UQAM. Pierre Dansereau did not follow the trend of specialized botany in the 1960s and complained to the author of the approaches, including a shift away from field studies and the abandoning of taxonomic knowledge as the fundamental element of biodiversity, while this term was being used indiscriminately in high places. One was no longer able to name the living, but wanted to protect it. Fortunately, things seem to be improving lately.

Pierre Dansereau remains a world-class thinker and his passing marks again the disappearance of a human being whose knowledge and scope remain incomparable.

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