It was a watershed moment.
In August 2012 I attended an international symposium in Vancouver about the effects of climate change on various species of reptiles and amphibians. With climate change accelerating, a litany of other threats, presentations ranged from how vegetation shifts were driving lizards to extinction to how captive-breeding programs for endangered species were being frustrated by climate-altered landscapes no longer suitable for reintroduction.
Between each came debate over the best approaches to conservation on a rapidly changing planet: some argued for moving species outside their historical range as a failsafe while others saw such "managed relocation" as risky, arguing for more traditional preservationist approaches. James Collins of Arizona State University summarized by wrapping the session with his paper "Ecological ethics and invasive species in a time of global change."
Afterward came standard questions about how to get average folk to care and how to engage policymakers, each answered with the usual entreats over carbon output and habitat destruction and blah, blah, blah. Though sincere and well intentioned, the tail-chasing continued until a shaggy-headed graduate student, otherwise listening implacably, interrupted. "Are we done talking about overpopulation?" he'd blurted. "When did that get taken off the table?"
Collins' eyes widened, and the room went silent as people probed the concept for themselves. No one volunteered to answer, and when the clock signalled break time, we'd all shuffled out, lost in thought and mumbling quietly.
It was a crux question: when was population taken off the table? For years I'd written about the travails of climate change, ocean acidification, pollution, habitat destruction, invasive species, emergent disease, biodiversity loss and extinction, alluding to population only in passing — like some kind of backseat passenger instead of a driver. And I wasn't alone. How had it become a bugbear in public dialogue?
Growing up in the 1960s, my own ecological awareness — in fact, the entire environmental movement — was rooted in the notion of a need to slow population growth. The precepts of Thomas Malthus' 1798 An Essay on the Growth of Population — much referenced by Charles Darwin as he formulated On the Origin of Species — and Paul Erlich's controversial 1968 book The Population Bomb were discussed in both elementary and high school. The ideas followed me into university in the 1970s and 1980s, not only in academic texts, but via popular literature.
"We are slaves in the sense that we depend for our daily survival upon an expand-or-expire agro-industrial empire — a crackpot machine — that the specialists cannot comprehend and the managers cannot manage. Which is, furthermore, devouring world resources at an exponential rate," wrote the desert poet, Edward Abbey.
And then, other than China's one-child policy that we all secretly admired... the population question disappeared.
Even today politicians seem genuinely afraid to broach the subject, and you rarely hear it mentioned in declarations emanating from climate meetings like Paris. Studies have shown that improved access to birth control is a valuable tool in slowing global warming, yet it remains the solution that no one will talk about, with Justin Trudeau's supposedly climate-conscious government apparently no different.
In the developing world, the population problem is seen less as a matter of numbers than of western overconsumption. And yet the main solution put forward by the development community for the problems of the developing world essentially exports the same unsustainable economic model fuelling overconsumption in the West. Travelling Southeast Asia this winter I was stunned by the exploding populations observed everywhere, especially among mountainous tribal groups least able to sustain this hedge against assimilation on thin local resources. This new "bomb" is a direct consequence of the prosperity that comes with a market economy and emulation of our consumptive lifestyle (which, ironically, my being there was part of). An example: Vietnam's population has grown from 75 to 90 million in under 20 years, an almost unfathomable 20-per-cent increase.
How much growth is OK? Very little. Urban planner Gabor Zovanyi noted that if our species started with but two people 10,000 years ago, and increased by only one per cent per year, humanity would today be a ball of flesh thousands of light years in diameter, expanding with a velocity beyond the speed of light. And if that's what it's starting to feel like around this solar system, maybe it's time to put population back on the table.