We are well on our way to a unified theory of biology that will merge body and environment, brain and mind, genome and microbiome.” – Deepak Chopra

Without healthy soil, there can be no health. Thanks to new technology, scientists are catching up to this view. The revelation underfoot involves “microbiomes,” now possible to explore thanks to gene sequencing.

Human Microbiome

The human genome is a map of an organism’s complete set of DNA, including all its genes. Though barely a decade has passed since this remarkable discovery, the cost of sequencing genes has lowered so dramatically as to make the exploration of other microscopic communities possible.

The human microbiome is one such community, comprised of microorganisms that live in, on and around your body. These are the “healthy” bacteria you may have heard about in yogurt or pro-biotics, some 100 trillion microorganisms that live in your gut, mouth, skin and elsewhere in your body. The number of genes associated with the human microbiome exceeds the number of human genes by a factor of 100 to one. Just as we’ve come to understand more about human health by understanding the genome, this map of bacteria, fungi, one-celled archaea, and viruses has shown scientists a microbial world of organisms with whom we have co-evolved, organisms that perform vital functions and services, and outnumber our own human cells by about ten to one. This has everything to do with the ground beneath your feet.

Soil is a Microbiome

Whereas we have long seen this connection, this new technology is making it possible for scientists to begin to quantify the link between soil microorganisms and plant nutrition. In the same way the microbes in the human body aid in digestion and help maintain our immune system, the microbial community in the soil offers symbiotic benefits to plants. Like fascia in the human body, roots and fungi (mycorrhizae) beneath the earth’s surface form a vast network that connects plants. A recent experiment in the U.K. showed how mycorrhizae actually enable plants to communicate.

In just one example a broad bean plant – under attack by aphids – transmitted a signal through its mycorrhizal filaments to other bean plants nearby, signaling those plants to produce a defensive chemical that repelled aphids and attracted wasps, a natural aphid predator. In much the same way yeast builds in a baker’s oven, the symbiotic association between plants and the fungi that colonize their roots is ongoing, albeit this partnership has been building for millions of years.

We take the connection one step further, linking the soil’s microbiome to the human one. To presume that human and soil-bound microbial communities begin and end in isolation is to ignore the mass of data about declining human health, and the wealth of data showing that the health of our soil has a direct effect on the level of our own health through the foods we eat, the water we drink, the air we breathe, even the amount of time we spend outdoors with nature.

Whether you acknowledge that link or not, it’s impractical to ignore the perils of diminishing our greatest natural resource, the soil of planet earth.

The good news is we can reintroduce the microorganisms to the earth. Mapping the soil microbiome – the work of the Earth Microbiome Project – will help identify species that are vital to soil and plant health, in order to replenish the earth.