Next Big Question

The Advocate

John Archibald, Fellow, Integrated Microbial Biodiversity program

The Pitch

Without microbes, we would not be asking any big questions because there would be no “us.” Microbes created our breathable atmosphere. They make the Earth’s soil fertile. They drive oceanic life cycles and extract megatonnes of greenhouse gases out of the atmosphere every year. The vast majority of biodiversity on this planet exists at the microbial level.

And that’s just the beginning. More than 90 percent of the cells in a human body are not human at all – they are microbes. Each person has between five and 10 kilograms of bacteria, viruses and other microbes living inside and on them – microbes that help us metabolize food, microbes that keep us healthy, and of course some microbes that can make us very sick. Some researchers go so far as to argue that there is really no such thing as a “human being” – that we are each a human-microbe symbiosis, with neither partner capable of surviving without the other.

Microbes make life possible in so many ways, and yet we know so little about them. For normal practical purposes, microbes are invisible, even though they are everywhere around and within us. And even when we do study them in the field or in our laboratories, they are not life as we know it – the way they trade genetic material and evolve and mutate is different from anything observable in macroscopic organisms.

There are very practical reasons why it is so important to understand how our existence depends on the microbial world – microbes can be used in disease prevention, industrial processes, environmental remediation and ecosystem management, and for many other pragmatic purposes. Even more important though, is that microbes provide a whole new way to understand the essence and the evolution of life on this planet.

At this moment, new technological advances, and new areas of research such as metagenomics are empowering scientists to attain a new and deep understanding of the hitherto inaccessible lives of microbes. Not only is this question big, but this is the right time to answer it.

The Bottom Line

“How do microbes rule the world?” is the Next Big Question because microbes are essential for our survival, and because we now have the capacity to understand and harness them better than ever before.