Editor’s Note: This piece is part of a new Minding the Campus article series called Minding the Sciences, wherein we are renewing our focus on the sciences given the many threats it faces in modern academia. Click here to learn more.
Sixty years ago, Rachel Carson warned of a “silent spring” to come. Presently, here in upstate New York, our long-awaited spring is anything but silent, filled as it is with chirping cardinals, phoebes, and goldfinches, buzzing bumblebees (which are not supposed to be here anymore), and that curse of the northeast spring, the despicable, whining black flies.
The silent spring has become environmentalism’s enduring vision. As in all millenarian ideologies, when Carson’s doom failed to appear, the faithful said to one another, “Not to worry, it will come.” This time, instead of pesticides wiping out the insects, it will be the “climate crisis” that does them in. So says Oliver Milman, who paints a dark picture of impending doom in his book, The Insect Crisis:
The first inkling of the cataclysm was the deathly stillness. The countryside, suburban gardens, and urban parks, their soundtracks now muffled, became lifeless imitations of themselves. No more rumbling buzzsaw of a passing bee, no metronomic chirping of a cricket, no nagging whine of a famished mosquito. …
The world’s insects had vanished, but the lag of human inertia meant that the first howl of horror, oddly, came not from us, but rather from the birds.
Not to quibble, but I don’t know of any bird that howls in horror, but never mind: perhaps Milman’s silent spring will not be so silent after all.
Milman is an environmental reporter for The Guardian, but he also is a monomaniacal climate catastrophist. Those recent fires in Quebec that have darkened skies all through the Northeast? Climate change! Pandemics? Climate change! Problems with penguins? Climate change! Goats fighting sheep? Climate change!
To be fair, Milman can claim he is only reporting on the work of frontline scientists, who he says are raising increasingly loud alarms on the state of the world’s insects. Milman’s message: to avoid catastrophe, follow the science and act now! To paraphrase the Proverb: Go to the insects, ye climate-denying sluggards, consider their ways, and be wise!
Last year saw several high-profile papers raise the alarm. In October 2022, Nature Climate Change published a lengthy article describing how climate change increases extinction risk for insects and other “ectothermic”1 animals. Oh dear! In July 2022, Ecological Monographs (a publication of the Ecological Society of America) published a multi-authored manifesto warning of the dangers climate change poses to insects. These include a loss of all the things insects do for us and for nature (the “tiny empires that rule the world,” as Milman’s subtitle puts it). Along with these came a spate of popular articles by environmental journalists, including Milman. Government also stepped in to reinforce the message. Consensus!
Are we really facing a climate-induced insect apocalypse? Probably not. The insects are species-rich, accounting for 90% of all the animal species on Earth. They have persisted through several mass extinctions, including the late-Permian extinction event 250 million years ago that wiped out 90% of the world’s fauna. They sailed through the Cretaceous–Tertiary mass extinction 65 million years ago, when an asteroid strike ushered about 30% of species (including dinosaurs) off the ecological stage. Yet, the insects endure because they are the planet’s most resilient and adaptable creatures. It’s a pretty safe bet that they will not be wiped out by a few tenths of a degree rise of global mean temperature.
What of those recent scientific publications that say otherwise? The bet stands, for two reasons. First is the echo chamber of climate doomsaying. The other is shortcomings in the science itself.
Climate change is not so much a scientific issue as it is a moral panic. It bears uncanny resemblance to the eugenics mania from the early twentieth century. Then, the panic was over racial purity, bolstered by the consensus support of nearly the entire scientific community at the time. Now, the panic is over changing climate—never mind that climate has always changed, and at magnitudes much larger than the present.
Moral panics arise from a closed positive feedback loop. All the protagonists in the climate change panic—journalists, governments, activists, and scientists—are enclosed in an echo chamber that amplifies the message at every turn. Scientists make a claim (insects are in trouble, we think it’s climate). Journalists amplify the claim in attention-grabbing articles. Funders step in to “help”. More scientists pick up on the hot topic and recast their work to be relevant. With every doom-mongering echo, rewards accumulate. The science journalists get clicks, which pleases the horde of foundations who are pumping millions of dollars into news organizations to pay their salaries. Scientists’ public profiles are enhanced, driving up the citation counts for their papers. This pleases their administrations and granting agencies, which bolsters claims for promotion, salaries, and more grant funding. Publishers love it because their quality metrics go up, allowing them to attract more authors (and lucrative page charges) to their journals. Once the panic has become sufficiently amplified, the cool rationality and skepticism that science is supposed to bring to debates like this becomes the unwelcome dog in the manger.
Even so, the appearance of scientific objectivity must be maintained. The EM manifesto’s seventy authors and nearly four hundred references are intended to project an air of scientific consensus and authority. The hedging qualifiers that permeate the text bely this. The word “may” shows up ninety-one times in the text, as in, “severe droughts may push the last remaining ephemeral populations toward extinction.” Then again, they may not. “I may win the Powerball and buy that Porsche I’ve always coveted.” Then again, I may not. Clarifying the odds should settle the matter in any case, but qualifiers that would help set the odds, like “probability,” are absent altogether. The authors’ “warning” thus amounts to uncertainty (severe droughts may occur …) piled upon uncertainty (… which may cause extinction)— hardly a reason to pay the warning any heed.
Behind the linguistic prestidigitation lurks a more fundamental scientific flaw. Climate science is a field dominated by physics. Most of the predicted consequences of climate change concern biology: extinction, ecosystem health, disease, pests, and so forth. To make credible predictions about the biology, the physics of climate has to meld coherently with the biology of climate adaptation. Presently, it does not.
A difference of scale causes much of the mismatch. The basic tool of climate science is the General Circulation Model (GCM). This divides Earth’s surface and atmosphere into blocks, or cells, of 250 to 600 kilometers wide and 20 to 40 km deep. The temperature of each cell can be calculated: global temperature comes from simultaneous calculations of the temperatures of all the cells. In contrast, insects operate on scales of centimeters. At such small scales, the temperature actually experienced by an insect can vary over ranges of plus or minus ten or more Celsius degrees relative to the cell temperature, more if the habitat is structurally complex. Forested landscapes are more structurally complex than grasslands, for example. This adds an order-of-magnitude layer of uncertainty over the already substantial uncertainty that comes out of GCM climate predictions. The statistical noise thereby becomes so large that reliable predictions of the effects of climate change on insects (or for any organism, for that matter) are impossible.
Paradoxically, this large uncertainty helps ensure that insects will be just fine in a changing climate. At the small scale that insects inhabit, the large variation of local temperature ensures a high probability that equable microhabitats will be available somewhere within those tens of thousands of square kilometers encompassed in a GCM cell. Patches of shade, perches under leaves, and adjustments of the time they are active are all opportunities for adaptation, which, be assured, insects will exploit. At a small scale, these adaptive opportunities are vast, making the likelihood of extinction due to a small shift of temperature commensurably small.
This brings me to a second fallacy, which Roger Pielke Jr. has called environmental determinism: that the fates of organisms are determined by their environment. If environmental temperature gets too high, say, this will determine whether an insect species lives or dies.
Environmental determinism is derived from a foundational concept of ecology, the Hutchinsonian niche.2 The ‘niche’ is a hoary concept that refers to where, and how, a particular organism fits into its environment: its place in nature. The Hutchinsonian niche is a variant concept of the niche which looks specifically at the physical interaction between organism and environment. A simple, and apt, example is the so-called thermal niche. Let us say an insect species functions well over a range of body temperatures: 30 to 35 degrees Celsius, for sake of argument. Outside that range, the species will not function well. Again, for sake of argument, let us say the environmental temperature of the species’ habitat ranges from 10 to 50 degrees Celsius. The insect’s thermal niche will encompass sub-environments within that range where environmental temperatures correspond well with the insect’s own range of functional temperatures. If those sub-environments are common, the species will thrive, because finding its thermal niche will be easy. If they are rare, or are decreasing in availability, the species will fail to thrive as its thermal niche disappears.
The supposed effect of climate change is therefore a theory of the thermal niche. A rise of global temperature will translocate an organism’s thermal niche to higher elevations, toward the poles, or to earlier in the spring. To persist, organisms will have to ‘follow their niche’ as it moves, either through physical translocation of their populations, or through genetic evolution. That is to say, their fate will be determined by their environment. Nearly all climate scenarios, including the hundreds cited in the EM manifesto, are environmentally determinist.
The logic might be sound, but the theory behind it is less so—this further undercuts the reliability of any predictions based upon it. The Hutchinsonian niche concept misses a crucial fact: organisms not only adapt to environments but also adapt environments to themselves. They construct their own niches, in other words. So, for example, the social insects I study are able to live in environments far dryer than their classically defined Hutchinsonian niche would allow. They do so by engineering the local hydrology on an ecosystem-wide scale. They adapt their environments to provide them with sufficient water, even in environments where water is scarce.
This phenomenon of “niche construction”, as it has come to be known, is ubiquitous in the living world, occurring at all scales, ranging from the humblest bacteria to the entire biosphere. Our oxygen-rich atmosphere, for example, is a planetary-scale constructed niche, as is, for that matter, global temperature. We have scarcely begun to grasp the implications of this, but one certain consequence is the overthrow of environmental determinism: life is not the slave of its environment, but its master. Any claim that fails to recognize this, no matter how many dozens of scientists make it, and no matter how many hundreds of references they cite, holds no water. These scientists do not account for the many ingenious tricks life has up its sleeve for dealing with changing climate, as life on Earth has done for roughly 3.5 billion years, and as it will do so for however long Earth is a habitable planet.
1 Ectotherms are creatures that rely on external heat sources to manage body temperature. Endotherms are creatures that use internally generated heat to manage body temperature. Mammals and birds are endotherms. Nearly all other animals (including most insects) are ectotherms.
2 After G. Evelyn Hutchinson. For an outstanding biography of this fascinating scientist, see Slack, N. G. and Wilson, E. O. (2011). G. Evelyn Hutchinson and the Invention of Modern Ecology, Yale University Press.
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