I know a veteran caver who dreams of traveling through subterranean passages almost every time they put their head to the pillow. This seemed a little crazy to me at first, but as I grow ever more enamored with the hidden realms beneath us, the same thing’s starting to happen to me. Just last night, in fact, I dreamed I’d slept in and missed out on a once-in-a-lifetime chance to go into Lechuguilla. Worst nightmare I’ve had in awhile.
Naturally, I’m also finding myself thinking way too much about caves during my waking hours. I’m always plotting my next adventures and contemplating vertical techniques and wondering about speleological science.
Speaking of the latter, it recently occurred to me to research the question: “What’s the deepest-living terrestrial lifeform?” I thought I’d quickly share the results of this query, because they’re pretty amazing.
Extremophiles, Simple And Complex
As with virtually all superlative features of local reality — the biggest canyon, the tallest building, etc. — there are a couple different potential winners here. It all depends on what kind of living thing we’re talking about.
If we’re interested in relatively-complex multi-cellular critters that are for sure living today, the winner is a worm called Halicephalobus mephisto. This little freak of nature has been found feeding on microbes up to 10,000 feet underground in some of the world’s deepest, darkest and hottest mines.
However, if we’re interested in the deepest life, regardless of how complex it is or how long ago it lived, the winner is a nameless bacteria that survived (and may continue to survive out of sight) some twelve miles below the planet’s surface 100 million years ago. That’s a long ways down, folks — a long, long, long ways down!
What I find so exciting about extremophiles like these is the way they radically modify our preconceptions regarding the limits of biology. Life, it turns out, is not always so fragile and picky after all.
If critters can make a living for themselves in some of the Earth’s most hostile environments, maybe it’s not so crazy to believe there could be life elsewhere in the universe — possibly even in our own solar system. Paradoxically, by looking inward we may be glimpsing the alien ecosystems of far corners of the galaxy.
- Worms Discovered In Two-Mile-Deep Gold Mine Are The Deepest-Dwelling Complex Lifeforms (Popular Science)
- Evidence Of Life That Lived 12 Miles Under The Crust 100 Million Years Ago (Daily Mail)
- Caves: The Truly Unexplored Places (Farther Still)
(Today’s image of evaporative speleothems at Timpanogos Cave National Monument is courtesy of Natalie Rae Good’s Tumblr.)