Mad: Engineer Humans to Combat Climate Change?
The threat of global climate change has prompted us to redesign many of our technologies to be more energy-efficient. From lightweight hybrid cars to long-lasting LED’s, engineers have made well-known products smaller and less wasteful. But tinkering with our tools will only get us so far, because however smart our technologies become, the human body has its own ecological footprint, and there are more of them than ever before. So, some scholars are asking, what if we could engineer human beings to be more energy efficient? A new paper to be published in Ethics, Policy & Environment proposes a series of biomedical modifications that could help humans, themselves, consume less.
Some of the proposed modifications are simple and noninvasive. For instance, many people wish to give up meat for ecological reasons, but lack the willpower to do so on their own. The paper suggests that such individuals could take a pill that would trigger mild nausea upon the ingestion of meat, which would then lead to a lasting aversion to meat-eating. Other techniques are bound to be more controversial. For instance, the paper suggests that parents could make use of genetic engineering or hormone therapy in order to birth smaller, less resource-intensive children.
The lead author of the paper, S. Matthew Liao, is a professor of philosophy and bioethics at New York University. Liao is keen to point out that the paper is not meant to advocate for any particular human modifications, or even human engineering generally; rather, it is only meant to introduce human engineering as one possible, partial solution to climate change. He also emphasized the voluntary nature of the proposed modifications. Neither Liao or his co-authors, Anders Sandberg and Rebecca Roache of Oxford, approve of any coercive human engineering; they favor modifications borne of individual choices, not technocratic mandates. What follows is my conversation with Liao about why he thinks human engineering could be the most ethical and effective solution to global climate change.
Judging from your paper, you seem skeptical about current efforts to mitigate climate change, including market based solutions like carbon pricing or even more radical solutions like geoengineering. Why is that?
Liao: It’s not that I don’t think that some of those solutions could succeed under the right conditions; it’s more that I think that they might turn out to be inadequate, or in some cases too risky. Take market solutions—so far it seems like it’s pretty difficult to orchestrate workable international agreements to affect international emissions trading. The Kyoto Protocol, for instance, has not produced demonstrable reductions in global emissions, and in any event demand for petrol and for electricity seems to be pretty inelastic. And so it’s questionable whether carbon taxation alone can deliver the kind of reduction that we need to really take on climate change.
With respect to geoengineering, the worry is that it’s just too risky—many of the technologies involved have never been attempted on such a large scale, and so you have to worry that by implementing these techniques we could endanger ourselves or future generations. For example it’s been suggested that we could alter the reflectivity of the atmosphere using sulfate aerosol so as to turn away a portion of the sun’s heat, but it could be that doing so would destroy the ozone layer, which would obviously be problematic. Others have argued that we ought to fertilize the ocean with iron, because doing so might encourage a massive bloom of carbon-sucking plankton. But doing so could potentially render the ocean inhospitable to fish, which would obviously also be quite problematic.
One human engineering strategy you mention is a kind of pharmacologically induced meat intolerance. You suggest that humans could be given meat alongside a medication that triggers extreme nausea, which would then cause a long-lasting aversion to meat eating. Why is it that you expect this could have such a dramatic impact on climate change?
Liao: There is a widely cited U.N. Food and Agricultural Organization report that estimates that 18% of the world’s greenhouse gas emissions and CO2 equivalents come from livestock farming, which is actually a much higher share than from transportation. More recently it’s been suggested that livestock farming accounts for as much as 51% of the world’s greenhouse gas emissions. And then there are estimates that as much as 9% of human emissions occur as a result of deforestation for the expansion of pastures for livestock. And that doesn’t even to take into account the emissions that arise from manure, or from the livestock directly. Since a large portion of these cows and other grazing animals are raised for consumption, it seems obvious that reducing the consumption of these meats could have considerable environmental benefits.
Even a minor 21% to 24% reduction in the consumption of these kinds of meats could result in the same reduction in emissions as the total localization of food production, which would mean reducing “food miles” to zero. And, I think it’s important to note that it wouldn’t necessarily need to be a pill. We have also toyed around with the idea of a patch that might stimulate the immune system to reject common bovine proteins, which could lead to a similar kind of lasting aversion to meat products.
Your paper also discusses the use of human engineering to make humans smaller. Why would this be a powerful technique in the fight against climate change?
Liao: Well one of the things that we noticed is that human ecological footprints are partly correlated with size. Each kilogram of body mass requires a certain amount of food and nutrients and so, other things being equal, the larger person is the more food and energy they are going to soak up over the course of a lifetime. There are also other, less obvious ways in which larger people consume more energy than smaller people—for example a car uses more fuel per mile to carry a heavier person, more fabric is needed to clothe larger people, and heavier people wear out shoes, carpets and furniture at a quicker rate than lighter people, and so on.
And so size reduction could be one way to reduce a person’s ecological footprint. For instance if you reduce the average U.S. height by just 15cm, you could reduce body mass by 21% for men and 25% for women, with a corresponding reduction in metabolic rates by some 15% to 18%, because less tissue means lower energy and nutrient needs.