In The Unlikeliest of Places

After hundreds of years of exploration, discovery and research, we’ve learned quite a lot about our planet.  You would think that after all of this time, there would be hardly any living thing left on Earth that we hadn’t yet found.  Well, you would be wrong.  Way wrong, actually.  Our planet is loaded with life.  New species are constantly being discovered – hundreds a year.  If I did a blog post every time a new species was discovered, I’d be posting multiple times a day.  Today’s blog post, however, is about one new species in particular which stands out among the rest.

The Amazon is
bursting with life

New species are often found in areas of the world that are harder for us to explore.  Oceans are a good example.  Rainforests are a great example.  The rainforests of the Amazon and Madagascar are constantly revealing new creatures to us.  Researchers in a rainforest in Borneo recently discovered a new species of mushroom that looks like a colorful sea sponge.  So much so, in fact, that they named the species Spongiforma squarepantsii, which is officially the most ridiculous species name I’ve heard since Dracorex hogwartsia.

(…So, a few years back, paleontologists discovered a new spiky-skulled dinosaur and donated it to the Children’s Museum of Indianapolis.  Inspired by the young visitors to the museum, the species was named Dracorex hogwartsia, the “Dragon King of Hogwarts.”  Yeah...  Of course, now some other paleontologists are arguing that Dracorex might just be a juvenile form of another dinosaur, Pachycephalosaurus, so the name might not stick around.  Call me a buzz-kill, but I won’t be too disappointed if it doesn’t.)

But I digress.

A paper recently published in Nature announced another new species found, not in a rainforest or in the ocean, but underground.  Deep underground.  A team of researchers traveled down into the gold mines of South Africa, down to a depth of over a mile below the surface, and they found worms.  But not just any worms!  These particular worms live deeper underground than any other known animal on the planet.

Extreme hot springs in Yellowstone

Biologists often talk about extreme environments.  By this they mean environments that are so harsh that almost nothing can live there.  People often say things like “The Dead Sea is so salty that nothing can live in it!” or “These hot springs are so hot, and so acidic, that nothing can live there!”  While it’s true that no fish, insect, or plant can live in some of the scalding, acidic pools of Yellowstone, or in the super-salty waters of the Dead Sea, there are microbes that flourish there.  All around the world there are single-celled organisms (Bacteria and Archaea) that are specially adapted to live places where no multicellular organism would stand a chance.  These organisms are called extremophiles – lovers of extreme environments, whether in hypersaline lakes, highly acidic pools, or pockets of water deep underground.

A mile beneath the surface of South Africa, there’s hardly any oxygen, and temperatures can be as high as 40⁰C (that’s 104⁰F for my American readers [and 313K for my physicists]).  This is no big deal really for extremophilic bacteria, so the scientists weren’t surprised to find bacteria doing just fine in water-filled fissures in the rocks deep underground.  What did surprise them were these worms.  Finding multicellular organisms so deep underground in such a hot, oxygen-poor environment was unheard of, and yet there it was, a tiny nematode worm, previously unknown to science, munching happily on the bacteria in the water.  They named the new species Halicephalobus mephisto, after the demon Mephistopheles.  Now that is a cool species name.

Now, extremophiles like H. mephisto are interesting by nature of being extremophiles, but biologists aren’t the only ones interested in these kinds of organisms.  The astronomers like them as well.  For a long time, astrobiologists have looked into Earth’s extreme organisms as inspiration for what life may be like on other planets.  If microorganisms on Earth can survive miles underground or in chemical-rich hot springs, could similar creatures be living underneath the surface of Mars?  Or perhaps in the ammonia-laden waters of Saturn’s moon, Titan?.  Do these extremophiles represent what early life was like billions of years ago when the Earth was harsh and alien?  And if so, could similar life have evolved on other planets with similar conditions?  

Shortly after being formed, the Earth was  a harsh place, hot, steamy
oxygen-poor, and constantly under assault by meteors.

Halicephalobus mephisto is a great example of how science always has more to learn.  If a worm can survive perfectly well miles below the surface, where no one ever expected to find one, who knows what other mysterious, wonderful creatures we still have yet to discover on this planet?  And who knows what mysterious worms and microbes might be waiting for us on other planets? 

So that’s why, when it comes to harsh living conditions, H. mephisto really is … the most EXTREME!!

(…There used to be this show on Animal Planet, you see…)