In Part-1 of the trilogy, I talked about ecological reality — what evolution entails and what is our stone-carved identity — a member of heterotrophs¹, which we should honor in order to be a moral human and avert short-lived prosperity. However, it is not immediately clear what “exactly” we should do to honor them as these realities exist at the meta-level beyond our common control.
I also mentioned that there is a slim chance for humans to engineer themselves to be autotrophic¹ in order to be more “morally free”, due to the higher bargaining power endowed by a lower dependence on other organisms. But even in this far-fetched scenario, we should not feel relieved, as our dependence on the environment still cannot be eliminated completely, due to potential disruption of the “dead” nutrient cycles (i.e., the non-living physico-chemical environment we call habitat), as evidenced also in the mass extinction(s) caused by early cyanobacteria, meaning themselves had suffered greatly albeit there was a second chance.
The power balance between autotrophic (producers) and heterotrophic (consumers) organisms is only one axis of the whole story that explains the stability of an ecosystem or society. In nature, among trees, animals, microbes, and in fact anything, whenever organisms co-occur in the same space, a fundamental evolutionary force always drives the segregation of their niches². Simply put, niche segregation occurs to avoid the direct competition of the same set of resources over space and time and thus enhance the co-survival of all parties involved (that’s why seemingly “unfit” species like sloths, pandas, kakapos can persist in the wild, before humans…). One of the most fundamental niche segregations manifests along the tradeoff axis of maximizing growth and dispersal rate vs. maximizing individual survival, scientifically referred to as the “r-strategist” for the high growth and expansion rate, quick reproductive cycle organisms on one end, versus the “k-strategist” on the other end for their high investment in individual survival leading to a longer lifespan (e.g., via high stress-tolerance) but at the cost of growth rate and fecundity (check here for more detail about life-history tradeoffs). Such niche segregation can even happen in the same individual at different ages to enhance cross-generational survival, highlighting the fundamental nature of this force.
To put it into another perspective, R-strategists are colloquially known as “opportunists” and are pioneers in a new/recently-disturbed environment, because they can take advantage of any untapped resources and unoccupied space much quicker (that’s why “invasive species” also tends to be r-strategists). However, these “new” ecosystems dominated by opportunists often wobble rapidly because of the fast unilateral consumption of their resources (or the production of waste) that leads to their own demise. The instability means they are inevitably replaced by other organisms with different life strategies gradually, and a more diverse community that has more balanced niches and traits ensues, one which utilizes and cycles resources stably over longer time to enhance co-survival. If succession does not take place, continual degradation of the ecosystem would occur (widespread cropland degradation is the best example as human intervention kept natural succession at bay). This is also one of the core reasons behind why the buzzword “biodiversity” just tends to make things better, strengthening ecosystem stability and productivity (learn more also from: Zhou et al., 2016; Caswell and Coe, 2013).
Putting these together, that is to say: ecosystems will keep deteriorating if the inhabitants’ r and k characters are not in the right balance. It then reconciles how our collective pace of life activities can tilt the fate between wobbly extinctions and stable evolution (see Part-2). Although there is certainly a huge variance of e.g., per-capita resource consumption pace within the human species, in a modern world context, it seems most societies as a collective group do not invest enough in stress adaptation and slow, stable development: developing nations have high population growth rate and developed nations, on the other hand, maintain a high rate of economic growth and expansion into any untapped resources via globalization and economic colonization (n.b. often times developed nations simply take advantages by acting via the hands of developing nations), which are both arguably r-traits. So collectively-speaking, modern humanity is an “off-the-chart” r-opportunist i.e., one that should lead to a wobbly world if the global biosphere fails to succeed to a more balanced set of life strategies. To “balance us out”³, in fact, other lives are paying the price for the time being, as evidenced in the ongoing sixth mass extinction. From an on-looker view, the rapidly growing crises we are seeing nowadays are no mere bad luck and this scenario has likely been played out billions of times since deep time non-exclusive to humans.
So both ecology and the Cambridge Dictionary tell us that being too much of an opportunist is problematic, at the very least many will need to tune down in order to prevent an eventual collapse of our pyramid of needs. But are we hardwired to be an r-opportunist? Have we always been this way? As always, genetics play a certain part, but as a high variability of resource consumption pace already exists within the human species despite we all share very similar genetics, I thus argue that genetics play a minor role in our r-behaviors. To further exemplify, we know there have been humans who lived in small groups, as hunter-gatherers, as small-scale forest gardeners, and in many other forms since prehistory that do not necessarily adopt a “habitat-clearance and expand” type of strategy. In fact, a hallmark of Hominid evolution (concurring with the increased size of the prefrontal cortex), is its strong association with the diversification of habitats, life strategies, culture and social organizations. Unfortunately, the skewed r-opportunist tribe has almost wiped the other tribes out completely, much like any opening scene of a “successful” invasive species.
In fact, sitting at the top of the food chain, free from other predators with a relatively long lifespan and low fecundity per parturition, we should be categorized as k-strategist in the strict biological sense (paradoxical, isn’t it?). Recent humans have “evolved” within a short time in ways not consistent with fundamental evolutionary tradeoffs, we have a longer lifespan, yet we produce more offspring, grow much faster and more stress-free individually, meaning that such evolution is not based in biology, but rather, in culture (our “accepted” attitude and habit of resource use and extraction) and technology (our capacity of resource use and extraction) i.e., we are cultural r-strategists, not biological ones. All these mean that we really, really do not have to edit our genes to make the changes we need to make.
We are of course free to pray that tomorrow there will be some miracle microbes popping out of thin air capable of converting all the different mountains of waste we produce back into vital resources without yet another harmful by-product, and then distributing them rightly back to the environment at the right pace. But I prefer to say that the responsibility is on us, quite clearly. What’s fortunate is that we could still use our biggest evolutionary gift — a wrinkly prefrontal cortex that empowers a conscious, flexible decision-making faculty (frankly, much prouder than having an “opportunity-taking” ability…). No doubt we are influenced by our genes, our “reptilian” brains and whatever deep-rooted habits i.e., egos and standards formed early in our lives, but they can all potentially be overridden by our highest-level conscious mental process. With this gift in mind, we shall be able to flexibly change our life strategies without resorting to gene-editing or magical drugs. So, if you don’t believe in a pre-determined, innate role for yourself (am a die-hard opportunist!), we have the last say on what we choose to be. Only with this in mind, can we master the most important attribute of all life — adaptiveness⁴. What do you want to be? Leave me a comment!
(I invite you to listen to this music to read it a second time if this article makes you feel conflicted.)
1. Heterotrophs are organisms that obtain their energy from other organisms to maintain their own life, whereas autotrophs derive their energy from either the sun or inorganic chemical reactions.
2. “Ecological niche” is, in the simplest term, just the way of living or the role of an organism. Organisms differed by what resources they depend on, how (fast) they use resources, when and where they are active, how their activities are affecting the habitat they live in etc.
3. Being dead can be viewed as the slowest possible state. Because of our very fast pace of life, the incessant cycling of elements forced some other organisms to be at their slowest state to “balance” us out (i.e., even if we did not directly kill them with our hands). If we are very fast, some others (be it fellow humans or other lifeforms) have to be very slow, like an inevitable “entangled pair”.
4. Stay tuned for an upcoming series in progress — “Adaptiveness — The true extent of adaptation”! It will explore the different levels that our traits and behaviors can change for the better.