An Ancient World Beneath the Waves

The ocean’s depths are home to organisms that have been around for nearly half a billion years.
  • Transcript


Question: What do you see at the bottom of the sea?

Sylvia Earle: The one thing that impresses me every time I go into the sea and it should impress everyone is the abundance of life.  The ocean is not just rocks and water.  From the surface it looks pretty much the same everywhere you go.  Sometimes it’s a little bluer or greener or grayer than others, but most people I think have the impression that it’s all about water and water of course is the key to life.  It’s the single non-negotiable thing that life requires, but because most of Earth’s water is ocean you kind of expect that is where most of life will be and that is the fact.  That is the way it is.  Dive into the ocean, there is life all the way down.  It’s like diving into the history of life on earth to look around when you’re in the sea because you see not just our fellow vertebrates, although there are plenty of them, the fish.  In some cases you have lucky encounters with whales or dolphins.  You might see turtles, fellow vertebrates.  You might even see if you’re in the Galapagos Islands iguanas, fellow vertebrates. But the great sweep of life is mostly not about vertebrates.  It’s about the invertebrates, creatures without backbones starting with the little tiny things, the microbes that rule the world.  They were in the ocean in abundance long before there were organisms that had multi-cellular structure. So having a chance to dive in and to be aware even though you can’t see them you know that you’re surrounded by this great sweep of tiny things that generate much of the oxygen, that grab much of the carbon out of the atmosphere.  The photosynthetic bacteria and other forms of photosynthetic life that are in abundance in plankton, you can’t really see them for the most part unless you have high magnification and divers usually just have a facemask.  You might see that the water is a little greener or not.  Sometimes you can actually see little particles, but those are relatively large compared to those really tiny things that even with the closest look you can deliver with your eyes you really can’t see the bacteria that are there in great abundance and in a just a you know a cup of water you may have millions of bacteria.  You may have a thousand different kinds of these little microbes.  It looks like water, but it’s still filled with life. 


And of course there are the bigger things.  If you’re down on the bottom you might see sponges.  They’ve been around for hundreds of millions of years; 400, 500 million years.  You might see starfish.  They’re ancient citizens too that go back 500 million years.  You might see jellyfish pulsing by.  Think about 500 million years, half a billion years.  Then you see some other creatures that have taken a little longer to form in terms of looking at the history of life on earth.  Horseshoe crabs have a history that goes back perhaps as much as 400 million years, but other arthropods, creatures that have jointed legs, crabs. Horseshoe crabs aren’t true crabs—they’re more closely related to spiders and scorpions even though they’re out there in the ocean, but crabs and shrimp and the little copepods that feed on the algae, the photosynthetic things that form the basis of much of the great food chains, food webs in the ocean.  All of that surrounds you as you dive in.  You see creatures whose history preceded that of certainly humankind or anything closely related to us.  Maybe sharks... they have a backbone or back cartilage anyway that have a history that goes back at least 300 million years.  We are really newcomers.  Our history is maybe contained within the last 5 million years or anything like human civilization.  Think about 50,000 years or really when you think about civilization with language and art and things that we really associate with who we think we are—maybe the last 10,000 years, since the end of the last ice age.  That is nothing in the history of the earth or life on earth.  As a diver you can think of yourself as almost an alien, a newcomer on this ancient planet filled with creatures whose life preceded that of humankind by hundreds of millions of years.

Recorded April 14th, 2010
Interviewed by Austin Allen