Walkerton tragedy highlights microbial ecology
ocean vents and drift high in the atmosphere. They are capable of enduring extremes of temperature, pressure and chemistry that would destroy more complex organisms.
We tend to think of them as germs, like the deadly E. coli strain that struck Walkerton. But microbes are just as important for their benefit to other life forms. Normal populations of E. coli in human intestines suppress the growth of harmful bacteria, and help metabolize our food, making various nutrients available for absorption into the blood stream. Without the microbes in their complex, four-chambered stomachs, grazing animals like cows couldn't digest the tough cellulose fibers which are a major component of the grass they eat.
The ability of microbes to thrive under extreme conditions is a legacy of their appearance early in Earth's history. It was this adaptability that enabled life to evolve in the primordial seas at a time when oxygen was scarce and the environment was hostile. When life began, the atmosphere consisted mainly of water vapour, hydrogen, hydrogen chloride, carbon monoxide and nitrogen.
Essential to life on Earth
Photosynthesis first occurred in organisms such as cyanobacteria, or blue-green algae, which used sunlight to manufacture sugars and produced oxygen as a by-product. This biochemical process in turn paved the way for higher life forms which require oxygen for metabolism. Progression from single to multi-celled organisms, and an oxygen-poor to oxygen-rich environment, occurred between 2.5 billion and 540 million years ago.
Microbes are so tough they can survive in outer space. Modern space exploration and discovery has discovered that other worlds within our solar system and beyond support conditions which could harbour simple life forms. These could resemble the bacteria that flourished early in our planet's development and still exist in every ecosystem. It is highly possible even for certain bacteria to be transferred from one planet to another in comets and asteroids.
With so much unknown about the origin and diversity of microbes, it is difficult to assess their importance to ecology and human life. They are certainly among the organisms most resilient to climatic change. This stability and adaptability is especially valuable to ecosystems.
Understanding the lives of microbes is important not only for preventing
more tragedies like the one in Walkerton. Microbial ecology is an essential
overtone to the lives of more complex plants and animals.