Despite the increasingly urgent need to change the way we live, consume and behave, we as humanity do not seem to make nearly enough progress towards halting climate change. Thus far, attempts to promote behavioral change with regards to food consumption, energy use and mobility have had limited effects. Likewise, effective market regulation strategies are limited, as international agreements are difficult to accomplish. Meanwhile, the clock ticks on and ‘last resort solutions’, such as geo-engineering, are considered more seriously as global temperatures continue to rise. 

A relatively unexplored field that could be considered as a ‘last resort solution’ is human engineering. The concept of human engineering was introduced in 2012 by scientists Matthew Liao from New York University and Anders Sandberg and Rebecca Roache from the University of Oxford. They propose that biomedical interventions in the human body could be used to mitigate climate change, for example by reducing a person’s ecological footprint and influencing our ability to take collective action.

Before introducing some examples of human engineering and explaining how human engineering could contribute to climate mitigation, I need to emphasize that I do not try to argue in favor of actual implementation of the biomedical interventions mentioned. Rather, I want to explore how our increasing knowledge about the human body can be considered when thinking about mitigating climate change to allow more discussion around this topic.  

An example of an environmental problem that could be influenced by human engineering is meat consumption. Animal-based products produce more than twice as much greenhouse gas emissions compared to plant-based foods, beef being the most polluting type of meat (see figure 1 and 2). Reducing meat consumption could reduce land use for agriculture by 75%, thereby reducing greenhouse gas emissions, while limiting further deforestation events and biodiversity loss. There might be a substantial group of people who are aware of this who would like to reduce their meat consumption, but still do not do so. The irresistible taste of meat, difficulties in breaking a pattern of habit or other reasons might be in their way. 

To help this group reduce their meat consumption, biomedical interventions could help by making eating meat less pleasant. By human engineering, the immune system could be primed to react to certain proteins in meat. Therefore, consuming meat results in an unpleasant physical reaction, which creates an aversion against eating eco-unfriendly food. There are examples of natural occurring meat intolerance, for example as a result of a tick bite. After a tick bite, a sugar molecule similar to sugar in red meat enters the bloodstream, causing the immune system to produce antibodies against this molecule. Consequently, the next time this person eats a steak, the immune system responds and causes an allergic reaction. Thus, strategies to induce mild allergic reactions against certain types of meat could be developed for people who want to eat less meat. Even though as a voluntary method this approach might not be effective (and as a forced approach comes with major ethical issues for obvious reasons), this example shows how the connection between our bodies and ecological footprints could be exploited to think about climate solutions. 

Other, even more extreme suggestions made by Liao, Sandberg and Roache, include embryonic selection to select for short people, since height correlates with ecological footprint (as taller people consume more, use more fuel for transportation and use more material for clothing). They also propose cognitive enhancement by drugs such as Ritalin to decrease birth rates, because there is a negative correlation between cognitive ability and pregnancy at a young age. These are just arbitrary examples of how changes in human biology could theoretically contribute to a more sustainable world. Of course, many other interventions in human anatomy and physiology could be thought of. 

Perhaps, a more powerful approach to combat climate change is to move beyond the individual level and orchestrate groups and communities to adopt a more environmentally friendly lifestyle. However, different worldviews, values and interests give rise to what is called the ‘collective action problem’, which makes it difficult to cooperate efficiently to achieve a collective goal, such as climate change mitigation. Philosophists Julian Savulescu and Ingmar Persson argue that we struggle with problems that act over large spatial and temporal scales, because human psychological abilities have not evolved as rapidly as our changing environment required. Climate change typically is a problem that will impact future generations more than it impacts us now and is difficult to observe locally. Our limited moral capacity prevents us from finding motivation to adopt drastic behavioral changes and give up (part of) our current lifestyle. To deal with this psychological obstacle, Savulescu and Persson have proposed the concept of moral bioenhancement in their book ‘Unfit for the future: The urgent need for moral enhancement’. By enhancing the moral decision making of humanity we would be better able to consider the needs of people far away in time or space when making decisions that impact the climate. 

How would ‘enhancing morality’ work in practice? Our increasing knowledge about regulation of moral decision making in the brain allows us to interfere with these biological processes. Therefore, certain qualities such as altruism and empathy, could be enhanced using human bioengineering to improve our moral decision making. The hormone oxytocin, for example, is known to enhance trust, conformism and the capacity to interpret social cues. Increasing the levels of this hormone could improve collaboration between people. In addition, noradrenaline reuptake inhibitors can affect moral decision making and could result in increased willingness to cooperate and increased desire to connect to other people. Thus, if we would ‘enhance morality’ on a larger scale, this could potentially benefit climate mitigation by enabling more effective collective action. 

Reading about these possible interventions in the human body might evoke feelings of discomfort or even aversion. Clearly, many different reasons can be thought of (and have been put forward by others) to argue why human engineering should not be implemented: fundamental ethical objections to interfering with human nature, practical issues with large scale implementation and uncertainty about effectiveness and safety, being just a few examples. I want to point out, however, that geo-engineering is part of the conversation, despite the consensus that modifying the climate at a global scale will pose major risks impacting all living beings on earth. Considering that human engineering carries lesser risks, as interventions would be based on administration of drugs that are already used safely in different contexts and can be tailored to individuals, I want to suggest human engineering should be discussed alongside ‘last resort solutions’ such as geoengineering. Even though biomedical interventions to combat climate change might seem unthinkable now, future generations might embrace the prospect of physical adaptation to climate change. From their perspective, I can imagine adopting some characteristics of the desert slender salamander could be useful when the next ‘hottest heat wave ever’ arrives…