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

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

SylviarnEarle:The one thing thatrnimpresses me every time I go into the sea and it should impress everyonern is thernabundance of life.  The ocean isrnnot just rocks and water.  From thernsurface it looks pretty much the same everywhere you go. rn Sometimes it’s a little bluer orrngreener or grayer than others, but most people I think have the rnimpression thatrnit’s all about water and water of course is the key to life.  It’s the single non-negotiable thingrnthat life requires, but because most of Earth’s water is ocean you kind rnofrnexpect that is where most of life will be and that is the fact.  That is the way it is.  Dive rninto the ocean, there is life allrnthe way down.  It’s like divingrninto the history of life on earth to look around when you’re in the sea rnbecausernyou see not just our fellow vertebrates, although there are plenty of rnthem, thernfish.  In some cases you have luckyrnencounters with whales or dolphins. rnYou might see turtles, fellow vertebrates.  Yourn might even see if you’re in the Galapagos Islandsrniguanas, fellow vertebrates. But the great sweep of life is mostly not rnaboutrnvertebrates.  It’s about therninvertebrates, creatures without backbones starting with the little tinyrnthings, the microbes that rule the world. rnThey were in the ocean in abundance long before there were rnorganismsrnthat had multi-cellular structure. So having a chance to dive in and to rnbernaware even though you can’t see them you know that you’re surrounded by rnthisrngreat sweep of tiny things that generate much of the oxygen, that grab rnmuch ofrnthe carbon out of the atmosphere. rnThe photosynthetic bacteria and other forms of photosynthetic rnlife thatrnare in abundance in plankton, you can’t really see them for the most rnpartrnunless you have high magnification and divers usually just have arnfacemask.  You might see that thernwater is a little greener or not. rnSometimes you can actually see little particles, but those are rnrelativelyrnlarge compared to those really tiny things that even with the closest rnlook you canrndeliver with your eyes you really can’t see the bacteria that are there rninrngreat abundance and in a just a you know a cup of water you may have rnmillionsrnof bacteria.  You may have arnthousand different kinds of these little microbes.  Itrn 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 mightrnsee sponges.  They’ve been aroundrnfor hundreds of millions of years; 400, 500 million years. rn You might see starfish.  They’re ancient rncitizens too that gornback 500 million years.  You mightrnsee jellyfish pulsing by.  Thinkrnabout 500 million years, half a billion years.  Thenrn you see some other creatures that have taken a littlernlonger to form in terms of looking at the history of life on earth.  Horseshoe crabs have a history thatrngoes back perhaps as much as 400 million years, but other arthropods, rncreaturesrnthat have jointed legs, crabs. Horseshoe crabs aren’t true crabs—they’re more closely related to spidersrnand scorpions even though they’re out there in the ocean, but crabs and rnshrimprnand the little copepods that feed on the algae, the photosynthetic rnthings thatrnform the basis of much of the great food chains, food webs in the ocean.  All of that surrounds you as you divernin.  You see creatures whosernhistory preceded that of certainly humankind or anything closely relatedrn tornus.  Maybe sharks... they have arnbackbone or back cartilage anyway that have a history that goes back at rnleastrn300 million years.  We are reallyrnnewcomers.  Our history is mayberncontained within the last 5 million years or anything like humanrncivilization.  Think about 50,000rnyears or really when you think about civilization with language and art rnandrnthings that we really associate with who we think we are—maybe the last rn10,000rnyears, since the end of the last ice age. rnThat is nothing in the history of the earth or life on earth.  As a diver you can think of yourself asrnalmost an alien, a newcomer on this ancient planet filled with creaturesrn whosernlife preceded that of humankind by hundreds of millions of years.

Recorded April 14th, 2010
Interviewed by Austin Allen