Sharing a building with Varsity, the university’s Centre for the Study of Existential Risk (CSER) has a name that evokes Cold War anxieties at odds with its bucolic surrounds at Mill Lane. The grazing cattle on Laundress Green are likely unaware that metres away a multi-disciplinary team of academics and policymakers is at work confronting the gravest questions ever posed to humankind. What are the potential consequences if the worst-case scenarios of climate models come to pass? What are the risks associated with the seemingly inexorable march of artificial intelligence?

The CSER has a broad remit to study the systemic risks facing the globe. The range of academic and professional backgrounds of its members is a feature meant to help the centre grapple with risks that do not take place in a vacuum, but rather as challenges within a web of interacting systems that underpin civilisation.

There are some profound risks that we are reminded of easily, thanks to an abnormal heatwave, or the unavoidable AI-generated slop flooding our feeds. Some risks though, those that originate from the microscopic realm, may lurk insidiously until they come to do us harm. This was illustrated all too well in the COVID-19 pandemic.

“A report published last year speculates on possible mass extinctions that mirrored life could bring about”

A July event at the CSER, jointly organised with the Centre for Pandemics Risk Management, hosted an expert on a risk receiving increasing attention, namely the future possibility of artificial ‘mirrored life’.

Many of the molecules that make up life on earth, like proteins and sugars, have a handedness, or ‘chirality’. This means that there exist, at least theoretically, mirror image versions of these molecules, called enantiomers, that have the same chemical formula as their counterparts, but for reasons of molecular structure, may interact differently with other chiral molecules. The proteins produced in an organism’s cells normally have a chirality that by convention is called left-handed. The reason that life ended up preferring one such handedness over the other is still debated. Any possible advantage of one choice over the other is thought to be subtle at the level of atomic physics, and there is nothing to preclude the existence of a form of life that is, in a sense, the precise mirror image of ours.

Why could this mirrored life pose such a risk? All forms of life have evolved over billions of years to fill evolutionary niches in complex ecosystems inhabited by life with a compatible handedness. A hypothetical mirror-organism may not face any of the naturally inhibiting pressures that organisms sharing our chirality face. For example, there is little understanding of how our immune systems might react in the presence of such organisms. A technical report published last year speculates on possible mass extinctions that the arrival of mirrored life could bring about. The thirty authors of this study include those previously awarded a grant with the objective to “design, construct, and safely deploy synthetic mirror cells” – having clearly determined that the object of their research poses an existential threat.

“Not promoting fatalism but actively thinking about the ways in which such disasters might be averted”

It remains to be seen when, if ever, humanity becomes capable of the synthesis of mirrored life, but more immediate biological risks are already on the radar of the CSER. In 2023, I sat in on a seminar at the centre delivered by Christopher Chyba, Professor of Astrophysical Sciences at Princeton. One of the topics he touched on in the talk was the increasing threat of a synthetic pandemic. Technological advances are streamlining and reducing the costs of the processes by which researchers can synthesise live viruses. In the near-future this may enable a rogue individual to create a dangerous pathogen almost single-handedly.

However dire that sounds, it was somewhat comforting to observe influential minds, including Professor Martin Rees, in discussions about such dangers at the CSER. Indeed, Chyba himself is not promoting fatalism but actively thinking about the ways in which such disasters might be averted.

In a 2012 article, he and Ali Nouri explain that while increasingly automated genetic synthesis technology may make engineering a pandemic easier, that automation also provides opportunities for oversight and safeguards to be implemented. This may sound counterintuitive, but an analogy might be that, although ChatGPT makes it very easy for us to synthesise text, there are safeguards in place so that it (usually) refuses to produce a manual on how to commit a crime.

If any of this has made you pessimistic, it is perhaps best to flip the logic on its head: The bright minds of Cambridge and beyond are collaborating to stave off extinction more than you might have known.