What is the biological equivalent of discovering the Higgs Boson?S

It looks like we're nearing the endgame in the hunt for the Higgs boson, the missing elementary particle of the Standard Model. Its discovery will send shockwaves through the physics community and likely capture the public imagination.

So the question, then, is what can other fields do to complete with all that? What events outside physics could pack the same punch as finding the Higgs boson? That's the question taken up in a fascinating article over at Nature, but the basic answer is one that's obvious when you think about it: the discovery of alien life.

Of course, contacting intelligent alien life elsewhere in space would utterly dwarf the Higgs boson in the popular imagination, but that still can't really be considered a particularly likely possibility, no matter how many exoplanets we discover. Of course, we might well find microbial life on some of the moons of Jupiter or Saturn, or perhaps traces of life that once existed on Mars. But the most intriguing possibility is the discovery of what Nature evocatively calls "the shadow biosphere":

Alien life - and a Higgs moment - might also be lurking close to home. Some have postulated the existence of a 'shadow biosphere' on Earth, teeming with life that has gone undiscovered because scientists simply don't know where to look. It could contain life that relies on a fundamentally different biochemistry, using different forms of amino acids or even entirely novel ways of storing, replicating and executing inherited information that do not rely on DNA or proteins.

The trick is deciding what to look for and how to detect it. The usual way that researchers search for new organisms - by sequencing DNA or RNA - will not pick up life that does not depend on them. Some scientists have speculated that desert varnish, a peculiar dark-coloured coating of unknown origin found on many desert rocks, could be a product of a shadow biosphere. Benner suggests looking in nooks and crannies that cannot support conventional life, such as areas with extremely high temperatures, radiation levels or harsh chemical environments.

Of course, as Nature points out, we came very close to just such a discovery a year ago with NASA's announcement of arsenic-based life - until that discovery utterly collapsed in the face of peer review. For more possible discoveries that could shake biology to its core, including the quest for immortality and the secrets of life's most ancient origins, check out the original article here.

Image by agsandrew, via Shutterstock.