I ended the first part of this post by asking, what if humans were a cancer – an unregulated accumulation of malignant biological matter? And what if they were attacking the planet’s ecosystems in the same way cancers attack organisms?
Well to consider this one has to first imagine the planet as being a life form (for argument’s sake). What if the planet was a huge mega-system consisting of interlinked constituent ecosystems, which behaved in the same manner as organ systems in an organism? Perhaps this system is the result of billions of years of co-evolution between organisms and their interplay with their environment. This is the idea behind the “Gaia Hypothesis”, later relabeled the “Gaia Theory” formulated by scientist James Lovelock and co-developed by microbiologist Lynn Margulis in the 1970s.
In this perspective, organic life is its own organism (for lack of a better word) that tries to survive and reproduce. Organic life (the biotic ingredients of nature) first appeared on Earth billions of years ago, then began to evolve into more complex organisms through its interactions with its environment (the simplest abiotic ingredients of nature). For example, single celled microorganisms were the first forms of life on Earth and they interacted with the molecular soup that was forming in the Earth’s waters to grow. They then grew into more complex forms like bacteria, which used surrounding water as the source for the electrons needed in photosynthesis – they then oxygenated the atmosphere through this photosynthesis process, making it easier down the track for life to grow and develop.
This interplay between the biotic and abiotic ingredients of nature, starting from the earliest single cell’s interactions with its surroundings, would continue to evolve for billions of years. The evolution of this interplay would spread organic life across the planet to form a billions-of-years old organic system that not only provided a habitat for life to grow, but allowed it to flourish. Gaia represents this earth system, an extremely complex web of interconnected biological phenomena which are themselves the result of interactions between the combined physical, chemical and biological components of the system itself. Whether we’re looking at the salinity of our oceans, the geochemical composition of the atmosphere, the rise and fall of surface temperatures and climate cycles, they are all influenced by interactions between plants and animals and the air, between fungi and water, between nitrogen and crops, ad infinitum. Organic life is all interconnected in a gigantic web of life that results in this one beautifully complex biological super-system called “Gaia”.
To simplify this, let’s assume that this system was a self-regulating organism. Now, I wouldn’t be surprised if some of my readers immediately ragequit out of my blog, shut off their computer and threw it at the nearest wall in frustration that someone would ever try to compare the planet to a complex organism. Obviously, the correlation is a bit farfetched. But it simply acts to provide an image or metaphor of how this biological mega-system called “Gaia” works. The key thing to keep in mind is that there is one key similarity between the idea of “Gaia” and that of an organism: they both rely on homeostasis.
Homeostasis is the process of self-regulation in organisms. To maintain the same stable condition of properties that allowed an organism to become what it is, that organism needs to regulate its internal environment. When a human is infected with a virus – say, influenza – its body needs to regulate itself so it can kill it off. But what happens when every organism on the planet goes through this process of homeostasis? And what if the end result of all of these organisms self-regulating themselves is that the whole system regulates itself. Remembering Carl Sagan’s quote in the first part of this post: “What a marvelous cooperative arrangement – plants and animals each inhaling each other’s exhalations, a kind of planet-wide mutual mouth-to-stoma resuscitation”. This is the beautiful complexity of how nature works: each organism brings something to the party that is an ecosystem, and everyone attending is able to partake in the festivities – and organic life, in all its forms, wins out.
But in order to maintain the same stable planetary condition that has allowed life to survive and prosper, Gaia (the overall earth-system) needs to regulate its constituent life forms to make sure it doesn’t overheat (to use a term from economics), which would be detrimental to all life in the system. There isn’t enough carrying capacity on the land to host and nourish every single life form that comes into existence. Herein lies the most poetic of the earth-system’s methods of self regulation: natural selection.
Only organisms that can contribute to the careful balance that sustains life in ecosystems can survive. Organisms which grow too fast will kill off their prey and die out. Organisms which cannot adapt to the continuous changes within the system as a result of its self regulation will not survive. But overall, life wins.
So what if it were possible for one malignant organism to figure out a way to survive this self-regulation and prosper? Let’s return to my spiel about cancer in the first part of this post:
Cancers are mutated cells that have lost the ability to self-destruct, and as the body doesn’t recognise them as foreign invaders (like viruses), their continued self-division within the body creates a build-up of tissues which form a tumor. If malignant, these cancerous cells can then spread across the body through one’s bloodstream and multiply, in a process called metastasis. This creates more tumors across the body, impairing certain tissues and organs, equalising their ability to serve their own function, and ultimately neutralising the role of a given organ system. Is this sounding familiar?
Metastasis is the enemy of homeostasis. Whereas homeostasis tries to keep the conditions within a body regulated and stable, metastasis tries to invade the body and use up its resources, thus impacting on these conditions. As Agent Smith from The Matrix appropriately points out:
Every mammal on this planet instinctively develops a natural equilibrium with its surrounding environment, but you humans do not. You move to an area and you multiply and multiply until every natural resource is consumed, and the only way you can survive is to spread to another area.
We humans operate like cancer within the earth system. We are not a virus, but organic matter just like all other organisms. Because of this, they do not treat us like foreign invaders, or viruses, and subsequently don’t try to regulate our existence. We therefore spread around the system as if through metastasis. But are we disturbing the balance of life on the planet? This is the topic of Part 3 of this post.