Only ever found on the surface where they convert sunlight into life-sustaining nutrients, how can a light-dependent organism thrive in total darkness?

A Sun-Kissed Glow

Cyanobacteria live in environments ranging from ocean shores to deserts, but up until recently, scientists had only observed these microorganisms in light-saturated environments. Typically, they use the sun’s light to power photosynthesis, converting carbon dioxide into oxygen and nutrients to help them grow. More commonly referred to as blue-green algae, cyanobacteria has been around for over 3.5 billion years, and it played a critical role in shaping the earth’s atmosphere.


Today, blue-green algae can be spotted in almost any pond or lake, bathed in sunlight and rich in nitrogen.

Below The Surface

Recently, scientists found the first confirmed colony of cyanobacteria 2,011 feet below the sun’s reach, thriving in a pitch-black cave. Previously, the only specimens of the bacteria that had been found in dark biospheres such as the cave had been isolated colonies and were thought to have been tracked in from the surface. The colonies of microorganisms living in the cave had kicked their sunlight habit in favor of a hydrogen-rich environment.


Scientists determined that the hydrogen-absorbing organisms differed very little from their surface-dwelling cousins, aside from lacking organs for photosynthesis.

New Horizons

The excitement of finding a new subgroup of such an ancient bacteria means more room for research. Scientists can now study these microorganisms in a new light, taking into account their newly-realized adaptability. To find such an organism so key to the development of our planet in an environment so vastly different from what had previously been known as an invitation to scientists for future study of microbiology.


If a key element of the primordial soup that shaped the planet can adapt over eons to live in total darkness, it is possible that life may also have adapted on other planets where major climate changes have occurred.