>> We're at 1,150 feet and
250 feet off the bottom.

>> NARRATOR:
Unchanged for eons, the dark,

alien depths and miles
of unchartered territory

of the deep sea
tease the curious

with their unexplored secrets.

>> Every time you go down
in the submersible,

there's always something
that's a surprise.

Every submersible dive
is a discovery.

>> My favorite thing
is seeing some things

that I didn't know existed
before.

>> NARRATOR:
Much of what lives in the deep

is little known or understood.

This includes
a group of animals

few people
have ever heard of,

some of which seem eerily
like an outstretched hand

reaching from the grave.

While others look
like a field of flowers.

>> From the first moment
I learned about crinoids,

I've been enthralled
with them.

I just think
they're beautiful organisms.

>> Crinoids are the sea lilies
and feather stars.

They're one big group
of the major branch

of animal life called
the echinoderms,

which includes the sea stars,
sea urchins

and sea cucumbers.

>> Crinoids are often
referred to as living fossils

because the forms that exist now
are very similar

to some forms that existed
during the age of dinosaurs.

They've been around
for a very long time.

>> Crinoids are found
all over the world.

There are Arctic and Antarctic,
and tropical crinoids.

There are some species
that are found

as shallow as just below
the low-tide mark,

and there are crinoids
in the deepest ocean trenches.

>> My belief is these guys
don't have natural deaths.

They die due to predation.

In other words,
they will live virtually forever

if you let them.

>> NARRATOR:
What remains to be discovered

about these living fossils?

What can modern crinoids
tell us

about their ancient relatives?

>> Major funding for this
program was provided by:

The Batchelor Foundation,
encouraging people

to preserve and protect
America's underwater resources.

And by Divers Direct
Emocean Club,

inspiring the pursuit
of tropical adventures

and scuba diving.

# #

>> NARRATOR:
Roatan is one of the bay islands

lining the Honduran Coast
in Central America.

It is on the southern tip
of the Mesoamerican Reef,

making it a popular
vacation destination

for scuba divers.

# #

Not far from
the island's shore,

a wall plunges
into the depths,

making the area
a perfect place

for deep sea exploration.

>> In terms of the
geographical set up,

it's just absolutely ideal.

# #

>> NARRATOR:
Submersible builder and pilot

Karl Stanley, who runs
the Roatan Institute

of Deep Sea Exploration,
set up shop

on the island's west end,
from where he motors

his submersible "Idabel"
across the bay

and then drops down
into the deep.

>> The deepest I offer trips
to the public is 2,000 feet,

but I've been to 2,660.

I actually designed this
for 3,000 feet.

>> NARRATOR : While the majority
of Karl's customers

are tourists with
an adventurous spirit,

his operation has also drawn
the attention

of marine scientists interested
in exploring the area.

>> I came to Roatan
based on a photograph

that Karl Stanley,
the submersible pilot,

took and posted
on his website.

>> NARRATOR: Dr. Charles Messing
is a professor

of Nova Southeastern
University's

Oceanographic Center
in Ft. Lauderdale, Florida.

>> We've just passed 1,000 feet.

No photosynthesis down here.

>> NARRATOR:
He has spent the majority

of his scientific career
studying

a little known group of animals
called crinoids,

some of which occur
only in the deep sea.

>> No one doubts that crinoids
are very obscure organisms.

The vast majority of people have
never heard of a crinoid.

Well, maybe they've heard
of the fossils,

but a sea lily?

What's a sea lily?

Is it some kind of flower?

Who knows?

>> NARRATOR:
The photo he saw online

featured one of the species
he studies.

>> What we know
about the biology of crinoids

is still pretty limited.

Well, we can certainly motor
along at that depth

and see if you can find them.

>> NARRATOR: So, together
with his collaborators,

he began conducting research
from Karl's sub in 2012.

Their goal is to answer
some basic questions

about the animals,

such as how long
they might live,

how fast they grow
and so forth.

>> I am particularly interested
in sort of aspects

of the function of organisms.

How do they work?

Sort of an engineering
perspective to biology.

>> About 185?

>> 185!

>> Famous last words?

See you later.

>> Water?

>> Water.

>> Still camera?

>> Still camera.

>> Snuggie blanket?

>> Snuggie blanket.

I feel like a professional.

>> Any time here we're going
to be going through

the thermocline,
which I also like to call

the free
air conditioning zone.

Now, we just need
to go straight down,

get neutrally buoyant
and start exploring.

>> Okay, we are on the bottom,

a big, yellow feather star
hanging down.

>> NARRATOR: Of the about
640 species of crinoids

found in modern seas,

at least 17 occur in the waters
off Roatan.

They include
the flowerlike sea lilies,

feather stars,

and the rather strange-looking
holopus.

>> There are three species
of holopus--

two here in the Caribbean
and one in the Pacific--

and they all look
pretty much alike.

When they're expanded,
they look like a little hand

with a very stout wrist.

And, basically, the wrist
is cemented on to the substrate.

There's no stalk.

And, of course, it's a complete
ring of ten arms,

but they look like fingers,
and they look like a gauntlet.

Like armored gloves.

And when they close,

they close up completely
and tightly,

so they look like a fist.

>> NARRATOR:
The arms allow crinoids to feed.

>> All crinoids
are suspension feeders.

They rely on small plankton
that drift by.

And they all have at least
five feathery arms,

and the side branches
of the arms

are called pinnules,
like a feather.

And along those pinnules

are tiny, little finger-like
structures.

And as the plankton drifts by,
these little fingerlike feet

just flick passing particles
of plankton into a groove

with microscopic hairs.

And that carries the particles,
like a conveyor belt,

down to the mouth
in the middle.

And the mouth
is right down in the base

of what would be the center
of the flower.

They have a complete gut,
with the mouth and the anus,

down in the middle.

They have a nervous system,
but no brain.

And they produce eggs and sperm
just like other animals.

(groans)

(laughs)

>> NARRATOR:
While diving in the sub,

the experts collect specimens
for further study.

>> Our sampling apparatus
is very, very simple.

It's basically a net
on the end of a stick

that we can scrape along
the substrate

and pop a couple of these
holopus off.

Bingo!

Wonderful.

>> NARRATOR:
Once back at the surface,

the specimens are preserved.

>> This is a holopus.

It gives you an idea
of how large the animal is.

It's about as big as they get,

and, of course, its arms
are all folded together.

You can see where
it cements onto the rock face

by its stump.

We are going to use
a series of preservatives

on some of the smaller pieces
for molecular work.

We're going to subject
the tissue to DNA analysis,

to try to understand
the evolutionary history,

who's related to who,

and develop an overall
family tree of crinoids.

The first family tree
of crinoids

using DNA sequences was
published about ten years ago,

but it only had a handful
of species.

So, we're continuing
to collect.

Now we're also looking
at RNA.

We can take little pieces
of the pinnules,

put them into
a particular solution

that will preserve the RNA.

And that we can use to look
at which genes are active.

>> NARRATOR:
Active genes reveal

how an animal is responding
to its environment.

For example, they may indicate
which genes are involved

in digestion, and the DNA
sequences of these genes

will help unravel
the evolutionary relationships

among different species.

Not all specimens
can be collected with a net.

>> We have a suction tube
that is powered

by one of the submersible's
thrusters,

and we can suck crinoids in.

>> NARRATOR:
With this suction tube,

the scientists collect
sea lilies,

feather stars, as well
as a potential predator.

>> In deep water,
we've discovered

that there's this sea urchin
that will prey on crinoids.

We know it does
because one of my colleagues

has found the skeletal pieces
of the crinoids

in the guts
of the sea urchins.

>> NARRATOR: The scientists
are particularly interested

in what is eating
and attacking crinoids.

>> Primarily,
what we're doing in the sub

is trying to look
at populations of crinoids

at different depths,
and we're looking

at the frequency
of regenerating arms

in each one of those
populations.

So, essentially,
the idea is that

in shallow water environments

where they're better
illuminated,

you would expect to see
more crinoids

with regenerating arms

because they're
being attacked more often

than you would in deep water,
where there is less light.

There, you would expect

much lower rates of encounters
with predators,

and you would expect to see
fewer regenerated arms

as a consequence.

>> Sea stars can regenerate
an arm that they've lost.

Crinoids are masters
of regeneration also.

They all start out
with five unbranched arms

when they're
really, really small.

But what happens then
for the ones

that grow more arms is,
they will drop an arm

and regrow two or four.

And they'll also drop an arm
in response to predation.

>> They've developed places
in the arms

that are analogous
to a lizard's tail.

So, a lizard's tail
is thought to function

as an escape strategy.

During a predatory attack,
it'll give up its tail

in order to escape.

Crinoids do something similar,

both in their arms
and in their stalks.

>> They can also regenerate
the lump of tissue

in the middle
that has the gut.

And so, if there's stress
or predation,

they can regenerate
the whole thing,

lock, stock and barrel.

>> There is no evidence
that they will

just sort of naturally die.

>> I may not be able to get it
because of the slope, huh?

>> We'll see.

>> NARRATOR:
While some species of crinoids

are permanently attached
to the bottom,

others have developed
the ability to move around,

likely as a response
to predators.

>> The majority
of fossil crinoids

and a number of living crinoids
have a stalk

that cements
to hard substrates,

and a few of them
have a root-like structure

at the base of the stalk
so they don't move around.

Other stalked crinoids,
a whole family of them,

have hooks along the stalk,
and they use them

as grapnels to attach
to hard substrates.

But they can actually
release them and lie down

and crawl around
with their arms.

And the feather stars retain
a little circle of hooks

with which they attach
to hard substrates.

And they can release them
and crawl with their arms,

and some of them
can actually swim.

The sea lilies
that we find here in Roatan,

we've got two species of them
so far

that have hooks
along the stalk.

Both of them can lie down,
detach and crawl away.

Let me get a shot
in the distance.

>> NARRATOR: To see how crinoids
grow and regenerate,

the experts take lots of photos
and record video,

which they compare
from year to year.

>> So, what we've established
are some locations

where we go and we'll return
to those over time.

And for these
deep-water organisms,

that's rarely done.

And so we hope to get a lot of
information about recruitment,

you know, the sort of
birth-death rates,

growth rates, and a variety
of other things--

interactions with other
organisms, predators;

fatalities due to predation.

So, we are pretty much
set on at least a five, six year

time frame at this point.

>> So when you look up,
you're seeing the edge

of the second wall,

and right now
that's 250 feet above us.

>> Karl's knowledge
of the local area

is quite amazing.

I mean, he's been here
for years,

and what he does is he'll drop
down to a certain depth.

You tell him, "Well,
these crinoids we're looking for

are in 1,100 feet."

So he drops down to 1,100 feet
in a certain area

and just motors along.

There you are.

>> My biggest navigational aids
are a compass,

which basically allows me
to know if I'm going

away from the wall
or towards the wall,

and then I have a fish finder
that tells me

how far off the bottom I am

and everything else
is based off of my memory

of the area.

>> How far is it to the fan?

>> We're halfway there.

>> NARRATOR:
Pilot Karl has been fascinated

with submersibles
from a young age.

>> I got started
when I was nine years old,

reading a short story.

And at that age, I said
I was going to build a sub,

started making drawings
that I still have.

>> NARRATOR: At age 15,
Karl started building

his first submersible,
which he completed

during his senior year
of college.

He operated that submersible
in Roatan for two years

before designing
his current sub.

>> "Idabel" is a completely
original design.

She's made of three spheres
of three different sizes.

The largest sphere
is four and a half feet,

and that's where
the passengers sit.

And that used to be part
of another submarine

that had been built in the '70s
for North Sea oil work.

I have fully redundant
propulsion systems,

separate battery banks,
four motors in the back

and separate switching systems

so that I can lose
any component

of my propulsion system,
battery, wiring, motor--

and it happens,
couple times a year probably--

and my passengers
never even know

because everything
is completely redundant.

That's one safety aspect
right there.

The other is, if you flood

the two ballast compartments
with air,

you're going to have
over 1,500 pounds

of positive buoyancy.

And then, you also have
a 450-pound lead weight

under the sub that you can
turn one bolt

from the inside and release.

So, then, basically,
you can have

a ton of positive buoyancy,

and you also have
vertical thrusters

that give you
another couple hundred pounds.

And then, I also carry
three days of air on board.

>> NARRATOR:
As of July 2013,

Karl had made more than
1,150 dives in "Idabel,"

including those with Chuck,
Tom and Forest.

>> I've been studying stalked
crinoids since high school

and yesterday was the first time
I was able to see one alive

and in its natural environment.

So, here you are studying
fossils for 20 years,

and you never see
the living form.

It would almost be like
someone who studied dinosaurs

since they were a kid
and then just happen to have

the opportunity to see one.

And so that's essentially
what happened for me

is I got to see my dinosaur,
my living fossil.

One of the reasons
that I love the fossil record

is because it gives you
a deep time perspective

that you can get
really in no other way.

It gives you an opportunity
to really study

how the oceans have changed

and how predator-prey dynamics
have changed.

>> NARRATOR:
Studying modern crinoids

can help answer questions
about their ancient ancestors.

>> Crinoids first appear
in the rocks

about 500 millions years ago,

and they have existed
in the oceans since that time.

There are at least
6,000 species

preserved in the rocks
that have been described.

Crinoids were most abundant
during the Paleozoic era,

which is the era that precedes
the age of dinosaurs.

>> The time we refer to
as the Mississippian--

340 million years ago--

was a time of great diversity
and abundance,

so it's thought
to be the peak

of their sort of
evolutionary success.

And during that time,
we had many, many crinoids

living in shallow seas
as well as deeper seas.

>> They were the
dominant organisms

in some of the ecosystems
back then.

Just miles and miles
of crinoid meadows.

>> At the very end
of the Paleozoic,

just before
the age of dinosaurs began,

there was a mass
extinction event,

>> What's called the "granddaddy
of all extinctions":

the Permo-Triassic extinctions
250 million years ago.

It's been estimated
that 95% of all species

that have lived
became extinct at that time.

Crinoids suffered heavily.

And, in fact, there is a gap
in the record of crinoids.

We see fossil crinoids
below it,

certain number of millions
of years,

and above it we see
just one.

We start off
with just a single taxa,

and it is believed to be
the ancestor

of all modern crinoids.

So, out of a group
that was incredibly diverse,

a single one
squeezes through.

And then it gives rise
to this modern-day diversity.

>> NARRATOR:
Crinoid fossils can be found

all over the world.

In the U.S.,
they are particularly common

in the Midwest.

>> I actually grew up
in Burlington, Iowa,

which is often referred to

as "the crinoid capital
of the world."

It preserves the remains

of about 350 species
of fossil crinoids.

>> Because about
300 million years ago,

that area
was a vast inland sea.

And there are tens of thousands
of square kilometers

of what we call
crinoidal limestone,

which is limestone
made primarily

out of the fossil remains,
sometimes tens of meters thick.

>> NARRATOR: And the discovery
of living crinoids

even played a part
in the beginnings

of modern oceanography.

>> Back in the middle
of the 19th century,

the general consensus was that
no life could exist

in the deep ocean.

>> NARRATOR: Then, in 1864,
a young fisheries officer

named Georg Sars dredged up
a sea lily off

the coast of Norway.

His father, the zoologist
Michael Sars,

realized it looked
very similar

to an ancient fossil crinoid.

>> This excited a lot of people,

because this suggested
that ancient forms of life

could exist in the deep sea.

Now, Charles Darwin
had just published

"The Origin of Species"
a couple of years before that,

which suggested
that organisms evolved

in response
to a changing environment.

If the environment
doesn't change,

they're not going
to evolve as fast.

There's no natural selection
pressure for them to do so.

>> NARRATOR:
After the discovery

of the ancient-looking sea lily,

scientists petitioned
the British Admiralty

for a ship to conduct
further research.

Eventually, that led to the
HMS "Challenger" expedition

in the 1870s.

>> Which was the
first round-the-world,

oceanographic expedition.

>> Karl?
>> Yeah?

>> If you can move the sub up
so the lasers

flank that specimen,
and I will try

to get a photo
with the lasers in there.

There is generation,
I can see that.

That is very cool.

We are looking at a holopus
I photographed last year,

and it was missing
a couple of its five rays.

And I can see regeneration
there.

Here, you can see
our scaling lasers.

Our scaling lasers
are ten centimeters apart.

That's about four inches.

And so, we can get
an absolute measurement

of how much growth
has actually taken place,

and that's a step.

And next year,
we'll absolutely know

what the exact rate
of growth is.

And it's really interesting
because we know

almost nothing
about these animals

apart from what depth range
they growth in

and where they're found.

So, this is the first
little piece of biology

that we've been able
to discover

about these animals.

>> NARRATOR:
Once back in the lab

in Ft. Lauderdale,
Chuck creates drawings

of the specimens
collected in the field.

Together with
the DNA analysis,

this will help
to better identify species

and understand
their basic biology.

>> For example,
this is the stalked crinoid,

one of the stalked crinoids
we collected in Roatan.

And it turns out

that there are three or four
different names of species

for crinoids that look like this
all around the Caribbean.

And it's not clear
where one species ends

and another one begins.

So, we're going to try to do
some detailed illustrations

and measurements
and try to figure out

what species it actually is.

We'll also have to compare it
to some museum specimens.

When I look in the microscope,

I see the image
of the critter

and my pencil and the paper,

and I can make
an extremely accurate tracing

of this species.

And the reason I do this,
there are structures here

that don't show up
terribly well in a photograph.

For example,
the details of the sutures

between some of the
skeletal pieces

are almost invisible
in a photograph.

I might publish
both a photograph

and an illustration like this

to show the important parts.

And there you go.

>> You ready to go?

>> We're ready to go.

>> NARRATOR:
Much remains to be discovered

about the seemingly strange
and astonishing life forms

of the deep sea.

>> Look at that.

This is the first time,
<font color = #FFFFFF>as far as I know,</font>

that this has been observed.

>> NARRATOR:
These little-changed organisms

provide a window
into the earth's past.

>> Crinoids are survivors.

They are beautiful organisms
that outlived the dinosaurs.

And there's much to be learned
by using both the rock record

and the living record together

to try to understand
the evolution and ecology

and history of a group
of animals.

>> Major funding for this
program was provided by:

Encouraging people
to preserve and protect

America's underwater
resources.

Inspiring the pursuit
of tropical adventures

and scuba diving.

And by the
Do Unto Others Trust.