MOUNTAIN LIFE - Blue Mountains | Fall 2018

46 ML BLUE FALL 2018 alter it—often irreversibly. And so, turning away from the simple wonders of ecology, Carson delved into the growing hornet’s nest of the latter. Alarmed by the sudden, unbridled post-war use of synthetic chemical pesticides, Carson set out to warn the public about their potential long-term effects. Silent Spring challenged the practices of farmers, agricultural scientists and governments, calling for a change in the way we viewed the natural world. Predictably, she was attacked by both government and the chemical industry, but continued to speak up about our essential human vulnerability—that as part of the natural world, we are subject to the same kinds of damage as any other part of the ecosystem. Carson died in 1964 after a long battle with breast cancer, but her work and zeal for the sanctity of all life continues to inspire new generations, her courageousness a beacon to scientists, students and environmentalists. Another woman who had a huge impact on my thinking kind of snuck up on me. When I was a graduate student at the University of Guelph in 1985, I attended the annual Hagey Lecture at the nearby University of Waterloo. Featured was American biologist Lynn Margulis (once married to the astronomer Carl Sagan), who spoke about the origin of sex in the context of her “serial endosymbiotic theory,” which had revolutionized the modern concept of how life arose on Earth. A decade earlier, in cell biology class, I’d heard about her dogged belief and eventual proof that mitochondria (the metabolic engines of cells) were actually descendants of primitive bacterial cells captured by other bacteria billions of years ago to create a symbiotic relationship that now formed the basis of the more complex eukaryotic cell on which the evolution of all higher life is based. Like Carson, Margulis was considered a radical, and her symbiosis ideas were greeted with skepticism and even derision, but eventually she was proved correct and we now universally accept that sequential symbiosis has been a powerful evolutionary process in the history of life on earth. Another radical Margulis idea dwelt in her long collaboration with British planetary scientist James Lovelock on the controversial Gaia hypothesis— the view that Earth itself is a single, self-regulating organism whose organic and inorganic elements are interdependent and whose life-forms (plants, animals, fungi, microorganisms) actively modify the planetary environment to maintain hospitable conditions. We now know the essential elements of this interdependence to be true (e.g., carbon and nitrogen cycles that span bedrock, soil, water and air), and it has application to both the evolution of life on earth and climate science. I could go on but it’s not necessary. Suffice to say, we have all benefitted from these fearless female pioneers of science who changed the world by challenging the way we see it. My own path through the discipline of biology was illuminated from the beginning by women who weren’t afraid to speak up about environmental justice and controversial theories, or to lend their passion and expertise to creating a critical mass around these issues. LEFT Katherine Johnson at NASA, 1966. WIKIMEDIA COMMONS ABOVE Lynn Margulis, 1980s. NANCY R. SCHIFF/GETTY IMAGES