Most of us can't even begin to comprehend the size of the world's oceans — and the amount of creatures that live there.
While we're all pretty familiar with the sea creatures that need to come up for air (dolphins, whales, etc.), and we know a good deal about the animals who live close to the surface (many types of fish), it's a totally different story when we talk about creatures that live in the deepest depths of the ocean.
These are organisms that survive on almost nothing. They require little sunlight or food to survive, and they are old — as in, millions of years old.
As one New Scientist story pointed out, "nearly dead" microbes at the bottom of the South Pacific exist almost impossibly.
Without scientists knowing exactly why, these microbes are alive (despite seeming dead for the most part). And they're 75 million years old.
How Two Microbes Changed History www.youtube.com
As microbes are located so deeply in the ocean (tens of thousands of feet, to be exact), there is essentially no sunlight reaching anywhere around where they live. And with no trace of sunlight, there is no trace of food. And yet, these microbes are alive. As New Scientist pointed out, scientist James Bradley speculates this is because the organisms have adapted to burn literally almost zero energy.
These microbes use about 0.00000000001 Joules of energy each year to survive. Compare that to the average human, who 97.2 joules a second, according to an article on environmental sustainability on the Bryn Mawr website.
This is to say that these microbes have slowed their functions down to almost a complete stop — a literally almost-dead kind of stop. And because of this, they are able to survive in an unsurvivable place.
Rob Knight: How our microbes make us who we are www.youtube.com
And as James Bradley says in the same New Scientist article, this could have major implications for life on otherwise unsurvivable planets. While a barren planet may look like it doesn't contain life, it's impossible to know what's living deep below the surface, or in the sediment.
Now we know, though, that even if we don't see it, it might be there. And even if we do see it and it seems dead, it might not actually be dead, either.