Philippe Bertrand has made his research career at CNRS (Centre National de la Recherche Scientifique, the main French research organization), as physical chemist and specialist in paleoceanography and paleoclimatology. His research first focused on the relationships between the activity of coastal upwellings systems and the climatic variations of the last glacial-interglacial cycles. He then became interested in the functioning of the Earth System as a whole, and devoted a book to it (Les attracteurs de Gaia, 2008) and many other publications. For several years, he supervised the research carried out by CNRS in the fields of ocean, atmosphere and climate (around 30 research units and observatories), which further strengthened his interdisciplinary background. It also reinforced his wish to link information from several disciplines to analyze the dynamic complexity and evolution of the Earth System over 4.6 billion years. He is a dedicated amateur photographer of the natural environment.Louis Legendre conducted his career in Canada and in France. He is professor emeritus at Sorbonne University, France, and Laval University, Canada. His fields of research are: marine biogeochemistry, biological oceanography, numerical ecology, and philosophy of science. His work is a blend of theoretical studies, laboratory research, and fieldwork. He tested his theoretical contributions by conducting research in tropical, temperate and polar waters, including the Gulf of St. Lawrence, Arctic waters and polynyas, the Greenland Sea, the Mediterranean Sea, lagoons of coral reefs and atolls of French Polynesia, the Sea of Okhotsk, the Equatorial Atlantic, and lakes. He received several prestigious honours and awards, including membership in three academies of science in Canada, China and Europe. His textbook Numerical Ecology (with Pierre Legendre) is used for research and university teaching all over the world. He enjoys the cultures, includingfood and drink, of countries where he worked and/or travelled extensively, especially (alphabetical order) China, France, Greece, Italy, Japan, Québec and Spain.
