Updated: Jun 1, 2021
(Before getting to the microbiome in detail, I think it's important to go over some background concerning issues that are going to interfere with being healthy because they interfere with the basis of health. That is, I can't explain why a loss of diversity in our microbiome is so potentially catastrophic unless it's clear why diversity itself is so important. And for that, we also need to appreciate that because humans are stuck in our ways, we are our own worst enemies.)
There are rules to this game
Humans have a love affair with technology and with very good reason. Throughout our history, our “problems” have been solved using our ingenuity, creativity, and engineering skills by designing solutions that are essentially outside the realm of the biological world. Truly, this one ability does indeed set us apart from the rest of the animal world because no other species can so readily synthesize a new material from existing natural materials to create new objects for the sole purpose of solving a problem.
One could argue that plants create sugar or that animals and plants generate organic polymers and these substances are novel and don't exist elsewhere. To a degree that's true, but making these substances is the result of processes based on very slowly derived adaptations. In contrast, the human ability to create IS the adaptation and the substances humans make are almost spontaneous creations. They are not based on genetic recombination or mutations; our engineering skill appears to be an emergent property of our large brain mass. Our ability to physically manipulate natural substances, even to create synthetic substances from other synthetic substances, is not an adaptation, but a property of our consciousness. Thus, we are different from other species and we use technology to manipulate and remake our environment to suit our own desires.
This god-like technical ability does not change a basic rule: we live in and must survive in a biological world. As much as some people would prefer to live in an entirely technological environment, we remain biological entities and there is no way around that. More than anything, we must grow or find food in the form of plants and animals. To do so, we have applied our skills and made uncountable numbers of tools to make that task easier. Over time, our tools for gathering food have evolved from pointed sticks to hydroponic-based greenhouses for growing plants and remote-sensing satellite technology for finding schools of fish in the ocean.
For every problem, real or perceived, clever humans have developed time or labor-saving technologies for increasing efficiency in our quest for producing food for our ever-growing population, which in turn is a result of our food producing prowess. We have become so proficient at applying technological solutions to these biological issues, that it is the mantra of all technologically advanced human societies that “science and technology will solve this problem.” We believe that there is literally no situation, biological or otherwise, that cannot be solved with a technological fix.
As I attempted to explain in Chasing the Red Queen (https://islandpress.org/books/chasing-red-queen), the habit of always applying technological solutions to biological problems has several inter-related drawbacks. First, technology tends to create a reliance on a single pathway to solving a particular problem which means we typically become blind to other options. If a solution works with any high degree of success, we fall in love with the solution and eschew all others in its favor. And technological solutions always seem so clever and futuristic and advanced. For many people, there doesn’t appear to be an acceptable answer to the question “what other options are there?” because new and advanced is always better than old and (therefore) primitive. And, of course, the truism that science and technology will find an answer is supported by all previous successes, each one built on the others.[i]
An important part of this love affair with technological advances and fixes is that we are willing to apply them before we’ve really had adequate time to consider and measure potential ramifications, especially negative side effects. The growing number of medications advertised on TV is a good example. While many possible side effects are mentioned, those are only the known side effects. There are very likely others that can’t be identified over the relatively short period of time that the drug was tested.
If the short-term side effects are not unreasonable, we don’t think deploying the technology is unreasonable. Thus, we tend to rush to apply new technology before we fully understand its long-term effects. Without going into detail here, this is exactly the source of problems associated with genetically modified crops, hydraulic fracturing, and below-ground nuclear testing. Just because we can do it, doesn’t mean we should do it before we have a more complete understanding of the long-term consequences.
Second, this linear and serial problem-solving process blinds us to the fundamental principles underlying the “problems” we are attempting to resolve. Complete reliance on a single conceptual approach to solving problems prevents us from recognizing inherent flaws in the approach and from devising more appropriate solutions. It is difficult for us to rethink our approach. Or if we do recognize a weakness, we either apply duct tape to the fix or we attempt to modify the fix to reduce the effects of the weakness.[ii]
This technological inertia means we will resist mightily the adoption of a new approach because we are so familiar with the current approach and have geared our entire system toward it. For an example, we need look no further than the automobile with an internal combustion engine and running on four rubber tires. As advancements in dozens of other technologies have come along, the automobile has become an extraordinary collection of radio and video entertainment, sound and climate control, wifi-Bluetooth-GPS connectivity, camera-sensor-automatic safety systems, but this extremely ornamented and technologically advanced vehicle remains an internal combustion engine, on four tires, governed by friction and gravity, with the sole purpose of transporting people from Point A to Point B. Even the shift to all-electric motors does not change the basic truth: the flying vehicles envisioned by Popular Mechanics in the 1950s remain an unfulfilled and empty promise because our focus remains firmly locked on the two-dimensional physics of the roadway. (And should flying vehicles become a reality, we will want to FULLY understand the consequences of letting everyone have a flying vehicle.)
A third drawback is that as biological systems, such as insect and bacterial pests, adapt to our technology, we quickly find ourselves applying new technological fixes to the old technological fixes that are failing. This is particularly problematic when a technological fix was very successful initially and failed over time; we “know” the technology will work and we believe that we merely need to develop the next generation of the fix. What we fail to appreciate is that no matter how successful the technology was initially, the fact is, it failed eventually.
In essence, we are relying on technology to fix our fixes, but we aren’t dealing with the underlying fundamental weakness: biological systems adapt to our technology and our technology cannot adapt to the biological systems without our assistance.
Fourth, technology is inert and is a simplistic and unstable way to work with living and responsive systems. Biological systems respond to stress by adapting, by evolving to reduce the stress, and in so doing they become different from the “problem” to which we first applied our “solution.” That is, the problem we identified and to which we applied the solution has changed such that the solution is no longer effective. In essence, technological fixes to biological problems are no more than attempts to hit a constantly and unpredictably moving target.
The technological solution cannot make appropriate adjustments to maintain effectiveness because the technological fix cannot recognize the evolution of the target. What is much worse, there is no way to anticipate the mechanism by which a biological entity (such as a bacterium) will evolve to alleviate the stress of the technological control (such as an antibiotic). There are an endless number of mutations that can cause a bacterium to become resistant or tolerant to an environmental stress no matter what the source. What we CAN predict without any fear of being wrong is that biological systems will adapt and technological solutions will fail.[iii]
Perhaps even more troublesome than the above-mentioned issues are the inherent properties associated with biological complexity. Complex biological systems (e.g., ecosystems with a high degree of connectivity between a large number of species) will possess inherent characteristics that the individual does not and cannot possess. For example, complex systems possess emergent properties, properties that exist precisely because of the number of individuals or species present. In population biology, this concept is captured in the phrase density dependence which is used to explain how and why some processes are observed only when population density is high.
For example, many of the differences between life in small towns and large cities is a function of the density of people in those places. In particular, we speak of “big city problems” because we recognize that those issues do not arise in small towns or, when they do, they are on a much smaller scale. These big city problems include social problems such as unemployment, gang violence, long lines, and impersonal service, but also include biological problems such as epidemics, depression, impatience, and a loss of connectivity to the natural world. While both large and small human groups have these same problems, the difference is one of intensity and the rates at which events occur, and the social visibility they acquire as a result.
The entire subject of Environmental Science is essentially based on the concept of density dependence. As the human population has grown, so too have the problems associated with density; they become more intense and more common. And some are emergent issues that only occur when populations are very large and dense. Pollution is an example in which small communities can negatively influence their immediate surroundings, but the problems would probably disappear if the inputs from the community stopped. In contrast, pollution from large metropolitan areas can affect entire regions and in permanent ways. The influence on the environment is intensified by the compounded effects of larger populations; the greater the intensity, the more likely the influence will override the capacity of the environment to absorb the problem. Thus, the pollution from a city ten times larger than a small city may have a destructive effect on the environment that is more than ten times greater.
The effect of human density on pollution from the large city has many variables and some may seem unrelated to the pollution itself. A large concentrated city population requires resources to be shipped in from greater distances than for a small population. The region surrounding the large population must support that population with food and building materials, and the ecosystem surrounding the large city will be greatly simplified for many miles in every direction. Housing developments displace the natural ecosystem and create a highly modified suburban buffer around the urban city. Air and water pollution changes ecosystem processes and reduces biological diversity as well. The ecosystem that is a human city is not only a highly simplified one, but it greatly disrupts and simplifies the adjacent natural ecosystems.
Complex biological systems can be resistant to disruption and, if they are disturbed, they can be very resilient and return to the pre-disturbance status very quickly. Complex systems are essentially buffered from the year-to-year vagaries of the environment. Most ecosystems are highly redundant in the sense that there are many different roles the species can play and there are typically many species playing each role.
This redundancy provides stability because the loss of a single species does not mean the loss of the function that species provided to the system. For example, the loss of a species of carnivore leaves a void that can be completely or partially filled by other species of carnivores. Many similar species would have to be lost before the function they provide is lost. Individual species are components of ecosystems; the ecosystem is built upon them and depends upon them, but is not defined by them.
When we apply a simple technological solution to a problem that is actually nested within a complex system, we cannot easily predict how the system will adapt to the technology. In fact, if we don’t understand how the “problem” is linked to or supported by the ecosystem, then we are defining the problem in human terms without understanding its biological or ecological foundation. For example, we have used synthetic pesticides to control unwanted insect pests in agriculture since the late 1940s. Each and every pesticide that has been in common and widespread use has resulted in the evolution of resistant pest species and this has resulted in a constant search for replacement pesticides as a counter measure. This back and forth battle to control a biological problem with a technological solution has no ending point and is the result of an unwillingness on the human side to recognize the underlying issue.
Agriculture is one of my favorite examples. Modern agricultural techniques have pushed farming toward an inherently unstable condition: the farm is a hugely simplified ecosystem lacking diversity, redundancy, and checks and balances. The microbial communities that once supported soil health and nutrient recycling are badly damaged. The top-down controls in the form of predators that ate the unwanted insect pests are long gone, having lost their habitats and having been the accidental victims of the early pesticides. The vast acreages of single crop types have made movement of beneficial species into the fields from surrounding habitats impossible or too slow to be useful.
The entire orientation of modern commercial agriculture is toward high efficiency and a dependence on artificial inputs such as fertilizers. The biological foundation underlying the growth of the plants has been ignored, lost, or devalued because of the nearly total reliance on technological “solutions” to the “problem” of growing vast quantities of “product.” In a very real sense, the practice of modern agricultural is nearly divorced from biology; we don’t grow food so much as we make it.
[i] It is certainly worth noting that all successful technologies evolved from unsuccessful attempts through a long trial-and-error process, but we very quickly forget how many unsuccessful attempts there were and instead focus on the single success. As an example, consider Thomas Edison’s invention of the light
bulb with the tungsten filament and the approximately 1000 failed attempts that led to his eventual success. [ii] Food-writer Michael Pollan, regarding solutions to problems in the food industry: “when it has a systematic problem....is not to go back and see what’s wrong with the system, it’s to come up with some high-tech fix that allows the system to survive.” Quote from the movie Food Inc. (2008) [iii] Grass-farmer Joel Salatin: “I’m always struck by how successful we’ve been at hitting the bull’s eye on the wrong target.” Quote from the movie Food Inc. (2008)