“Arsenic-Based” Life in Mono Lake

The internet is abuzz with news of a new “arsenic-based” life form found living in Mono Lake, CA.

Mono Lake at sunset

One of the reasons for the buzz is that there is a constant whisper of “aliens” in the stories and blurbs.  One reason for this is that Nasa funded the research and made the announcement about the discovery.  Another reason could be the lake itself.  Mono Lake is a photographer’s hotspot because it is home to absolutely gorgeous tufa towers.  The photographs from the site are straight out of sci-fi and they lend the story an exotic, other-worldly feel.

Since the mention of aliens tends to short out the brain’s rationality circuits, here’s the scoop, sans ETs.

Tufa towers are limestone formations that develop in saline rich lakes

First of all, the life-form in question is a bacteria designated GFAJ-1.  It is not an arsenic-based life-form, meaning arsenic is not a natural part of it’s genetic makeup.  Dr. Felisa Wolfe-Simon put them in an environment where phosphorus was removed and arsenic put in it’s place.  Phosphorus is one of the main building blocks of life as we know it, it forms the backbone of our very DNA.  Arsenic is a deadly poison.  However, instead of dying off in the toxic environment, it thrived.  GFAJ-1 was able to adapt and replace its phosphorus with arsenic.

You may be wondering “How does someone even come up with an idea like this?”  It’s actually not so big a stretch.  GFAJ-1 belongs to a group of bacteria called Oceanospirillales which are known to have a flexible approach to their diet.  Some of their cousins are currently helping the environment in the Gulf of Mexico by eating spilled oil.  Mono Lake, where GFAJ-1 is found, has a number of arsenic deposits.  And, arsenic is only one step away from phosphorus on the periodic table of elements.  Combine those three things and you get an idea that’s so crazy it just might work.  (BTW, the Mono Lake Community staff would like you to know that the lake is not toxic and has a surprisingly “productive aquatic ecosystem.”)

The truly fascinating thing about all this is that there is an alien element to this story.  Dr. Wolfe-Simon is working for NASA’s Astrobiology Program, which “supports research into the origin, evolution, distribution, and future of life on Earth.”  One of her goals is to broaden the definition of “life as we know it” so that as we explore more of space we have a better chance of recognizing alien life which doesn’t conform to the standards we have set.  In her words:

“It may prove that there are other possibilities that are beyond our imagination. It opens the door for us to think about biology in ways we have never thought. We are going to look for life on other planets and we only know to look for that which we know. This may help us to develop tools to look for something we have never seen.”

All I can say is, Gene Roddenberry totally called it forty-three years ago.  May I refer you to the first season episode, “The Devil in the Dark,” where the crew, Dr. McCoy in particular, is baffled by a silicone-based life form that is terrorizing a mining colony because they keep killing her eggs.  Dr. Spock taught me not to assume that life on other planets would conform to our ideas of normal when he mind-melded with the scary rock monster.  I am reassured to know that the scientific community is preparing for this sort of thing.


Photo Sources:

Lake Mono Sunset

Mono Lake Tufa Towers

By [E]SaraB

Glass artisan by day, blogger by night (and sometimes vice versa). SaraB has three kids, three pets, one husband and a bizarre sense of humor. Her glass pendants can be found at if you're interested in checking it out.

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