Pollen and spores: Microscopic keys to understanding the earth's biodiversity

The most distinctive feature of planet Earth is that, unlike any other world in this solar system, it is rich in biodiversity. Our own species, which evolved as part of the biosphere that sustains us, has the intelligence and curiosity to explore the world around us and to understand its complexity. Given the environmental challenges that lie ahead we have much to learn by exploring all aspects of biodiversity. One astonishingly informative field of investigation is palynology, the study of the pollen grains and spores of plants. These microscopic, self-contained biological units are surrounded by chemically resistant cell walls with distinctive structures and symmetry. They can provide insights into such fundamental questions as how and when plants first colonised the land or how the earth's vegetation has developed through geological time and on finer time scales. They provide phylogenetic evidence important in plant systematics and model systems for understanding plant development at the cellular level. This short voyage through the microscopic world of pollen grains and spores is a personal account of the interest and importance of these microscopic keys to understanding the earth's biodiversity.