The Red Queen Hypothesis

Leigh Van Valen, in his seminal article published in 1973 on The Journal of Evolutionary Theory, A New Evolutionary Law, introduced to the rest of the world a dark and disturbing fact that should trouble any person alive today in our post-coronic times, particularly if you recognize Homo Sapiens as the dominant species (and want to keep it that way). In this article Van Valen recounts with erudite craft how he went through monumental archives of fossil remains spanning millions of years, carefully cataloguing and inferencing the rise and fall of thousands of species and, more generally, taxa through the ages (taxa, plural for taxon, is a taxonomic group of any rank, such as a species, family, or class). Though the records are painfully incomplete, decades of careful cataloguing and sophisticated statistical analysis can yield patterns from these disparate remains. Indeed, what Van Valen found, hidden in all the data, is a timeless story, and perhaps a lesson to all those used to trophic dominance as the apex predator. What he found was evidence that the statistical probability that any one species becomes extinct is not at all dependent on the age of the species, nor its evolutionary fitness. What is instead suggested by these data is the following:

  1. The probability of extinction remains constant throughout a taxon’s existence.
  2. If the rate of evolution and adaptation falls below the baseline extinction rate or, more restrictively, the rate of its competitors, the taxon becomes extinct.
  3. The evolution of taxa and the competitiveness or extinction are best described with unimodal, stochastic models.
Stochastic model of taxa. Note unimodal distribution (single peak) and the correlation of competing taxa peaks with the decline of others.

This result, lovingly proved, and further justified by new evidence, solidified the theory under which these phenomena are explained. This paper has hundreds of thousands of citations, and is very well regarded in the scientific community. However, and the reason that some of you might be interested in this at all, is the strangely suggestive name given to this proposition, The Red Queen Hypothesis. In brief, this behavior is explained by the dynamics under which the evolutionary process develops, wherein taxons compete in (approximately) zero-sum competition to capture as much energy as possible from their environment, in the forms of greater adaptation to its environment as well as growth in its population. A taxon will, in its increasing mastery of energy, not only require constant adaptation to preempt the risk of extinction (which is constant), but also require even greater expenditures of energy or adaptation to continue growing and, crucially, remaining competitive against new threats. The finding evoques some colorful imagery from the children (and occultist) classic Alice in Wonderland–Through the Looking Glass, whereupon meeting the Red Queen in her spiraling chessboard realm, she advises Alice:

Now, here, you see, it takes all the running you can do, to keep in the same place. If you want to get somewhere else, you must run at least twice as fast as that!

What is perhaps not too clear here is is how this excerpt relates to the previous claims. It turns out that due to the extinction rate being constant throughout some taxon’s history in the fossil record, the pressure to compete or adapt to the environment remains a constant threat to the expansion of this taxonomic group. When applied to the dynamics of some taxon near the peak of its growth, the competitive pressures from other competing species become greater in proportion to how close this species is to dominating the trophic space. When one species becomes the dominant life-form or it reaches its peak of dominance, it is in direct competition with the greatest number of other life forms in its ecosystem. Its pressure to evolve to stay competitive against a greater number of species is eventually what leads to the end of growth, as in the (pre)historic records show there is no species capable of harnessing energies without directly challenging all others.

This alone is quite fascinating, and morbidly parallel to accounts of civilization collapse explained through decreasing marginal returns to complexity and energy extraction. And this reference to Tainter is not incidental, for what we find here is a theory of exponential increase in evolutionary pressures driving dominating species from their position of growth and superiority to a position of decline and submission. What should be noted here is that the moment when one expects competitive evolutionary pressures to be at their most pressing is precisely when some species finds itself at the peak of dominance. It is hard not to wonder if this in turn applies to our current position in relation to our ecosystems, and indeed I would hold that position, that given our level of unprecedented dominance and the fragility of the human sphere in relation to its equilibria with the broader biogeochemical cycles and our financially unsustainable position in the absence of continuous exponential growth. The question is not whether or not we’re at our peak, but rather when will the stage of decadence set in. We could go even further and ask, what will be the cause?

While I among many others feared climate change as the critical event that could lead to the end of mankind’s dominance, these findings suggest we discount the relative importance of this factor and instead focus on those pressures that could emerge from other species. And here is where the horror creeps in. What if the latest outbreak of Coronavirus was merely the prelude to the longest and most bloody conflict in human history, yet one that has for millenia been repeated and whose terrible outcome is to be extracted from the fossil record. What the Red Queen Hypothesis suggests is that perhaps we should take the risk posed by deadly disease very seriously, for in the present state that our species finds itself, our vulnerabilities to disease have ceased to decrease with technological development, and have started to increase with the problems posed by scale, connectedness, and eventually the rise of bioweapon-grade diseaseases. It is not an easy truth to acknowledge, but the fact is that trivial experimentation with pathogens can lead to disproportionally catastrophic consequences, and that you might one day too get your viruses from some nerd’s garage just as you did your personal computers, should make anyone pause. This is not to claim that coronavirus was an engineered weapon, but that this is the teaser of a dark world to come, one where handshakes threaten and coughs betray, and where a bit of tinking in the lab or a festering market can crunch the world economy in mere weeks.

What I suggest is that we begin to guard ourselves a little more closely against these pathogenic threats. I’m not sure what’s going to happen, but I can say with confidence that things are changing around the world, and people are starting to think differently about the real, run-out-of-food, die-without-medical-treatment risks that we face. In this regard, perhaps we should be thankful that it was coronavirus that forced us to react, and not some far deadlier pathogen. Here is one way in which an arms race will surely doom us, for the side we work with to build our weapons is inhuman and uninterested in our military aims. Tread carefully in this new era of viral dominance, I will close with a few words from the research article that led to my discovery of this hypothesis, written by Indrė Žliobaitė, Mikael Fortelius, and Nils C. Stenseth, published in Nature, Reconciling Taxon Senescence with the Red Queen Hypothesis:

“On the basis of the modelling results and analysis of fossil data, we propose that the Red Queen’s hypothesis (emphasizing the role of competition in driving evolutionary rates) primarily relates to the peak in occupancy during taxon history. Because natural selection at any time maximizes the expected amount of expansive energy, evolutionary success is defined not by simply staying alive, but is instead driven by expansion. In this view, traits are adapted to functional demands in a deterministic manner, but which particular taxon next acquires a better-adapted trait is mostly random.”

“Expansion stops at the peak, the point at which the taxon begins to fail in the competition and starts to decline towards extinction. The path to extinction ends with the extinction event, which occurs when the taxon becomes too rare to be detectable in the fossil record or disappears entirely. Small populations are more exposed and more vulnerable to environmental changes, and a small geographic range in declining populations has been shown to be associated with a higher probability of extinction.”