NOVA

PATRICK HUNT: He's the oldest human specimen we have that is so complete.

So well preserved.

AARON DETER-WOLF: He continues to generate this body of information.

HUNT: He may well be the most studied human being in history.

NARRATOR: The Iceman.

HUNT: He was found in a glacier, frozen in time for 5,000 years.

NARRATOR: An ancient murder mystery... Ready to go?

What can we learn from him?

What is his story?

We figured he was probably Italian.

Wrong.

Eastern European?

North African?

Wrong, wrong, wrong.

Where's this guy from?

NARRATOR: Scientists search for answers hidden in his genetic code... CARLOS BUSTAMANTE: We're rewriting the history of humankind.

NARRATOR: As an artist brings him back to life.

When they believe that it's real, then I have done my job.

NARRATOR: Science and art join to share the Iceman and his secrets with the world.

GARY STAAB: We have to turn this thing from plastic to flesh.

NARRATOR: "Iceman Reborn," right now, on NOVA.

(alarm ringing) NARRATOR: In a custom-built lab, a team of doctors suits up.

Strict precautions are taken.

Okay.

NARRATOR: Because this is a very unusual case.

The patient has been dead for over 5,000 years.

This is tzi, the Iceman.... one of the oldest and best preserved intact human bodies ever found.

The story of tzi's discovery is still one of the most astounding in human history.

1991-- on a 10,000-foot glacier near the border of Austria and Italy, two hikers come across the body of a man face down in the ice.

They have no idea the importance of what they've stumbled upon.

Perhaps it's a mountaineer, or even a lost soldier from World War I.

But as they pull the remains from the ice, capturing the recovery on video, certain clues point to a different story-- a knife made of stone; a shoe made of grass; a quiver of arrows; leather leggings; a copper ax.

Carbon dating later reveals that the body and the items found with it have been preserved in the mountain ice for over 5,000 years.

tzi becomes not only an international sensation but also a scientific treasure.

He's the oldest human specimen we have that is so complete, so well preserved.

With all the scientific disciplines that are intrigued by him, that want answers, he may well be the most studied human being in history.

NARRATOR: Now, new technology is yielding more clues, revealing surprising secrets about this mysterious ancient man and the world he lived in, from the strange markings that cover his body to the DNA in his bones.

Researchers are trying to use his genetic code to uncover his true origins, to track down his relatives, alive, even today, and help solve long-standing mysteries about how people lived at the end of the Stone Age.

tzi provides a window into what life looked like 5,000 years ago in Europe.

So it's kind of like finding the Ark of the Covenant.

How important is that?

Yeah, it's pretty important.

NARRATOR: The clues begin with tzi himself.

At the time of his death, he was about 45 years old, 5'2" tall, weighing about 110 pounds.

New research deciphering tzi's genetic code reveals he had brown eyes, dark hair, and had both Lyme disease and a predisposition to heart disease.

But that's not what killed him on the mountain.

At first, it was thought that the Iceman had frozen to death in a storm and been buried in the snow.

But a radiologist reviewing his x-rays spotted something strange that had escaped everyone else's notice: an arrowhead lodged deep in the Iceman's shoulder.

ALBERT ZINK: The arrowhead was detected in 2001.

And then the question was did the arrowhead kill him or not?

NARRATOR: CT or CAT scans of the body revealing tzi's internal anatomy in amazing detail provided more clues.

We could reconstruct then the area where the arrow entered the body and disrupted a major artery of the left arm.

If you're losing so much blood, after ten to 15 minutes you are dead.

From this, we knew that he was killed by this arrow shot.

NARRATOR: Shot and left to die on the mountain.

The mystery was deepening.

Who was tzi?

What did he do for a living?

Who were his people?

And why was he killed?

The answers will not be easy to find because tzi's condition is so delicate.

tzi has spent years locked in a freezer at the South Tyrol Museum of Archaeology.

His cell, kept at a chilly 19 degrees, is designed to protect him from potentially destructive microbes.

No one enters the sterile environment except tzi's doctors.

ZINK: The Iceman is kept under sterile condition in this refrigeration cell.

And that's why we have to take care who's entering the cell, because we want to avoid that anybody brings in any kind of contamination.

(alarm ringing) Yeah, ready to go.

NARRATOR: Today an exception has been made for an artist named Gary Staab.

Gary has been charged with a difficult mission-- to sculpt an exact replica of the Iceman, a copy that will be accessible to researchers and to the public who can't get close to the real thing.

We cannot allow everybody entering the cell who has maybe a certain research question to inspect the mummy.

We want to make a good copy people can use to see, to get very close, to get data which cannot be done with the original mummy, it's always really a risk.

STAAB: Nail bed, pinky, nine millimeters.

NARRATOR: Gary has limited time to take in all the details of this rare and unique human body.

STAAB: I am soaking in every single detail I can lay my eyes on.

NARRATOR: He must create the most accurate replica possible: tzi's twin.

STAAB: Right index, five millimeters.

NARRATOR: He evaluates tzi's skin tone and texture... STAAB: The keratin has fallen off the nailbeds.

NARRATOR: His distorted face... STAAB: That cartilage is so, so thin.

NARRATOR: His ravaged hip... EDUARD EGARTER-VIGL: Yes, you have a very big defect of soft tissues and bone tissues.

STAAB: Because of the damage, this will be very difficult to replicate.

NARRATOR: In the process of getting every detail just right, Gary will have to learn all he can about the Iceman and his times-- how he lived, died, and became mummified.

STAAB: What is his story?

What can we learn from him, and how can he enrich our understanding of the past?

Okay?

STAAB: Very good.

NARRATOR: Dr. Eduard Egarter-Vigl calls an end to Gary's visit.

Any more thawing and the Iceman could be in danger of bacterial contamination.

STAAB: Absolutely amazing.

That was the fastest 30 minutes of my life.

This very intimate moment with the mummy will be very helpful in the final product.

It will be so much better because of that.

NARRATOR: With tzi safe in his sterile crypt, Gary will begin to bring his body double to life.

To start, the CT scans that helped determine tzi's cause of death will provide a detailed blueprint for the Iceman's twin thanks to a remarkable technology... 3D printing.

tzi will literally be printed out in three dimensions.

HERLIEN DECLERCK: We use our software to transform the CT images into a 3D model that you can print.

NARRATOR: Special software converts the data into a stack of over 2,000 horizontal slices, creating a blueprint of tzi's body.

This is then fed into a computer, which controls a gigantic five-foot by 18-foot machine known as "the Mammoth."

They have the ability to create the entire print in one piece, which is very rare.

NARRATOR: In this enormous vat, 350 gallons of liquid resin the consistency of warm honey will be transformed into a life-size plastic model of the Iceman.

The computer guides lasers around a thin layer of liquid resin.

We use a laser to trace out cross sections of tzi and under UV lights the polymer starts to harden.

Once it solidifies, just a few seconds, a very thin layer is positioned on top of it and the laser hardens it out again and this way the model is built layer by layer.

NARRATOR: For nearly three days, the lasers continue their work, little by little, until every small bump and hollow on the surface of the Iceman's body is present and accounted for.

STAAB: This is very exciting.

We're using the newest technologies to three-dimensionally print the oldest wet mummy ever found.

NARRATOR: Finally, it's time to reveal the 3D print.

Oh my gosh, this is fantastic.

NARRATOR: Transformed from liquid to solid.

The face details are beautiful.

That is absolutely fantastic.

NARRATOR: tzi's body has been reconstructed as one extremely detailed hollow piece of plastic.

STAAB: Beautifully translucent but it still captures all the forms and the shapes.

NARRATOR: As the model emerges, the Iceman is reborn.

STAAB: tzi coming out of this resin was kind of overwhelming.

Because slowly his face was revealed, his feet were revealed, his ribcage.

And it was super exciting to know that that three-dimensional print was at such a high resolution, I really have something to work with.

NARRATOR: It is on this plastic tzi that Gary will sculpt the life-like version.

STAAB: It's a treat to see it in one color because there's nothing distracting your eye.

I'm also looking at anatomical features that correspond to the structures that I saw in the freezer.

NARRATOR: While Gary reviews tzi's plastic form, scientists continue to hunt down clues about the flesh-and-blood man.

NARRATOR: For Albert Zink, who oversees research on the mummy, tzi's CT scans are especially valuable because a look at tzi's muscles and joints can tell us a lot about his life and lifestyle, perhaps even how he made a living.

The two main ways of life 5,300 years ago were farming and hunting and gathering.

ZINK: You can reconstruct the muscles, the muscle structure, how the muscles are attached at the bones.

We just could extract all this from the CT scans.

NARRATOR: Zink notices tzi did not show signs of strain in his upper body muscles and joints.

That might rule out farming.

ZINK: In his upper part, in his shoulders, in the arms and hands, there is almost nothing, and for a man which was about 40 to 50 years old in this time period, we would expect some changes if he had worked with his hands.

NARRATOR: The scans do indicate severe damage in the muscles and joints of his legs and back, which suggests he was a constant traveler.

Also, the mummy's knee and hip joints are missing a lot of their cartilage-- a painful condition called arthrosis, a kind of arthritis caused by wear and tear.

The physical facts of the Iceman were that he had lower back problems.

The same is true for the knee.

We know he had some arthrosis of the knee joints, and this caused pain from time to time.

NARRATOR: tzi died in the mountains and he likely spent much of his life there, too.

We know from his physical appearance that he was walking a lot, that he maybe was carrying some heavy things.

So maybe he was trading something.

It could be that he was really traveling a lot.

But we cannot really say what was his role in society.

NARRATOR: Searching for even more evidence about this enigmatic man, scientists perform a kind of autopsy on tzi.

They remove specimens from inside his most culturally sensitive organ...

This is stomach here.

NARRATOR: His stomach.

And they are able to extract tzi's last meal, eaten only hours before his death.

Some of the contents point to tzi being a hunter.

DOCTOR: So much material from the stomach now.

BUSTAMANTE: He had wild ibex meat in his stomach, so he was clearly hunting for part of his sustenance.

He also had einkorn wheat.

Einkorn wheat has to come from farming.

It's this classical kind of interesting mystery.

tzi's sending us mixed messages about how he's living his life.

NARRATOR: In addition to food, researchers also found different kinds of pollen in the Iceman's stomach.

This revealed that tzi had been traveling up and down the mountain within the last 48 hours of his life.

tzi seems to have been a man on the move whose adventures came to a violent end.

More than 5,000 years later, tzi's twin is on a journey of its own across the Atlantic Ocean, all the way to Kearney, Missouri, in the American heartland.

Here, Gary Staab brings ancient fossils back to life.

He is a master model maker, and over the years he has been commissioned to build replicas of dozens of extinct creatures for museums around the world.

He has fashioned prehistoric fish, sculpted life-size dinosaurs, and crafted giant crocodiles.

STAAB: I've spent entirely way too much time on the inside of large animals.

NARRATOR: From the miniature to the monstrous, whether it swims, crawls, or flies, Gary's job is to resurrect the long dead.

STAAB: So the fascinating fact is that 99% of all life that has ever existed on earth is extinct.

So, I follow floods.

I follow volcanic eruptions, mass death events.

I'm a bit of an ambulance chaser, but I'm just a little bit late.

Maybe a few thousand years late.

In some cases, 50 or 60 million years late.

NARRATOR: Gary's investigations-- all to better understand his subjects and the worlds they lived in-- have taken him around the globe, from exotic excavation sites to ancient fossil fields.

STAAB: Most of the time my job is to sculpt animals for museums.

And we only have their bones.

We only have fossils.

So I have to take something that no one is exactly sure what it looked like, and try and breathe life into it.

This is a neat situation; we know exactly what Iceman looks like.

So my job is to replicate him exactly as he looks right now.

What's in here?

NARRATOR: Now Gary faces one of the biggest challenges of his career: creating the exact replica of tzi the Iceman.

It's like Neolithic Christmas.

NARRATOR: The plastic model generated by the 3D printer has just arrived in his studio.

STAAB: It was an amazing feeling to finally lift him out of the crate and take him onto the table.

By the time we're finished, we will work thousand of hours.

NARRATOR: 3D printing technology has provided the artist with a good head start-- a model with physical dimensions exact to the millimeter.

It's a perfect match to the shape of the Iceman, but the surface of the model is not detailed enough to create a believable replica.

We've got a lot of work ahead of us.

NARRATOR: Gary and his team will need to sculpt tzi the old-fashioned way-- all by hand.

STAAB: There is not one centimeter of this thing that isn't complicated.

It's going to be very hard.

NARRATOR: It will be a four-part process.

Sculpting, molding, painting, and crafting minute surface details will take Gary and his team months to complete.

STAAB: The challenges are many.

We have not only the elements of the skin texture, we have the detail of the face.

We have the detail of the hands.

And we have to figure out how to replicate the hips.

The hip is going to be very challenging to do.

You guys start on this end and work your way up and I'll start on the head and then I'll meet you somewhere in the middle, I hope.

NARRATOR: The first step: darken the mummy's body to better reveal the exact contours of the 3D print.

STAAB: We can't actually read the surface when it's translucent.

So we take a very dark and penetrating stain and we paint it over the top of the three-dimensional print.

It allows us to see the surface in a much better way.

So we can read those shapes, and then actually make judgments on how we're going to sculpt the surface based on what we see.

There are thousands of considerations-- not hundreds, thousands of considerations, that have to be taken into account for while you are doing this.

NARRATOR: Next, Gary replicates tzi's skin with especially malleable modeling clay.

As the thin clay bonds to the resin, Gary and his team sculpt every detail of the mummy's surface texture, inch by inch.

Getting tzi's skin just right is one of the main challenges for Gary and his crew.

We have to turn this thing from plastic to flesh.

NARRATOR: Human skin is actually an organ-- the largest we have.

On average, it takes about 20 square feet of skin to cover a human body.

It will take hundreds of hours to replicate tzi's complex mummified surface.

Pick out some of these that might work well and then run some samples.

NARRATOR: Gary relies on texture pads to press patterns into tzi's clay skin.

STAAB: I have hundreds of textures in a box.

I pulled them out to see which ones might match.

NARRATOR: These flexible rubber patches create varied imprints on the wet clay.

Human skin has three layers.

The epidermis, or outer layer, acts as a waterproof wrapping and a guard against infection.

It also determines our skin color.

The next layer, the dermis, is made up of tough connective tissue, along with nerve endings, hair follicles, and sweat glands.

Finally, the deep hypodermis consists of subcutaneous fat and more connective tissue.

Gary and his team are sculpting the second layer of tzi's skin-- the dermis.

Most of the outer layer was lost to the mountain.

(translated): If you look at the skin of this mummy, you have to realize that this body has been lying in ice for years.

The ice isn't always stable, so in summer, the ice melts into water.

If it's in water for too long, the upper layer of the skin, the epidermis, separates and you lose it.

The layers underneath, the dermis and the subcutaneous layer, remain preserved.

A lot of hair, fingernails, and toenails have been lost.

NARRATOR: Enough of the Iceman's skin, along with soft tissue and muscle, has been preserved to make tzi a true mummy.

For Gary, tzi is not the first mummy he has replicated, but certainly one of the most unique.

Mummies can be created naturally or artificially.

Artificial mummies, like those from ancient Egypt, were made by intentionally blocking the decaying process.

The important thing during mummification is that it happens immediately.

So the natural process is the degradation or the decomposition of a body, so it has to be stopped immediately.

NARRATOR: This was the case for one of the most famous mummies of all: the Egyptian pharaoh King Tutankhamun.

He was embalmed and then coated in a black resin-like liquid that encased and preserved his skin.

But in natural mummies like tzi, or those discovered on mountaintops in the Andes, or bog bodies found buried in peat, the environment alone preserves the body.

ZINK: The Iceman is a natural mummy.

He was naturally captured in the ice.

And he's also a humid mummy, so he still contains some water in his tissue that makes him also so difficult to preserve.

NARRATOR: It is luck that tzi was preserved at all.

He was nearly lost forever.

Fortunately, his body lay in a small trench, protected by large rocks on two sides.

This trench eventually filled in with ten feet of snow and ice, preventing the Iceman from being swept into the deadly frozen current that flowed around it.

ZINK: This makes him also quite unique.

He's one of a few ice mummies that exist at all, and he's the only natural ice mummy we have in the Alpine region.

NARRATOR: The ice preserved tzi, but the great weight of the glacier eventually flattened his body, creating the ultra-lean frame that Gary is now duplicating.

After weeks of work, the replica is covered in a layer of white clay that matches the texture of tzi's body.

But in order for Gary to finish the face, he must remove tzi's head.

STAAB: It's much easier to sculpt away from the body.

So you have to bring it to where you can focus, get exactly in a zone where physically, you can work on it for that length of time and not get ultra-fatigued.

NARRATOR: tzi's face presents a particular challenge.

STAAB: This will be the thing that everyone looks at.

They'll engage it in the face, in the eyes, and that's where they will spend most of their time.

This is where he will become a person to them.

He has a really wild-looking face.

It's a bit grotesque in some ways.

His lip is actually pushed up here because he was lying face down on a rock, and that pressure on his face and over his nose.

The nose is so difficult to tease out the details of what's actually happening there-- you know, what am I actually seeing, what's doing what-- so that it can be correct.

It's entirely possible I will know his face better than his mother did.

NARRATOR: After months of sculpting, molding, and crafting the exact details of the Iceman, Gary has reached the most visible stage in his process.

STAAB: I'm at a very exciting point.

NARRATOR: The paint.

STAAB: Finally, I can actually put color on.

Painting is a very fun part of this process, and it's very fun to see this come to life through color.

NARRATOR: From the rims of his eyes to the tips of his toes, Gary must match every inch of tzi's skin to the original... ...including the mummy's mysterious markings...

Many sets of parallel lines... ...and two crosses.

These are tzi's tattoos.

The Iceman is the oldest tattooed mummy ever discovered.

STAAB: It's complicated because there's so many.

Yes, he's covered with a lot of tattoos.

NARRATOR: Researcher Marco Samadelli has been one of tzi's caretakers for nearly 20 years.

How did you catalogue each one of these?

NARRATOR: Recently, Marco set out to inventory every tattoo on tzi's skin.

We discovered exactly 61 tattoos.

STAAB: That's a lot of ink.

(translated): It's difficult to see the tattoos on a 5,000-year-old mummy.

NARRATOR: Marco's research revealed something no one had ever seen before, thanks to a unique camera sensitive to invisible light.

(translated): Multispectral imaging is a technique used to see what the eye can't see.

It's with this we discovered every single detail, even under the surface of the mummy's skin.

NARRATOR: The exact number and location of all the tattoos was a mystery until now.

(translated): We discovered a tattoo that had never been seen before: four parallel lines on the right side of his chest.

We were able to locate all his tattoos and obtain a complete mapping.

AARON DETER-WOLF: 61 tattoos arranged in 19 groups across his body.

NARRATOR: Archaeologist Aaron Deter-Wolf studies the use of tattoos in ancient cultures.

DETER-WOLF: Tattooing has been practiced throughout a huge portion of human history going back at least 16,000 or 18,000 years before present.

During that time period, people have been tattooed for all sorts of different reasons depending on their culture and the region in which they lived.

NARRATOR: Aaron has come to Gary's studio to demonstrate how and why he believes tzi's tattoos may have been made.

We're going to take a piece of pigskin, which is a proxy for human skin, and we're going to use these reproduction tools to tattoo that skin in the same patterns that are on tzi's body.

NARRATOR: Aaron thinks tzi's tattoos were most likely created with a technique that was widespread in the ancient world: by using a sharp needle, probably made from bone, to puncture the skin and push ink, made from charcoal, into the tiny shallow wounds.

DETER-WOLF: What you want to do is just dip the tip of the tool, and then you're just going to go in very, very shallowly.

NARRATOR: Microscopic and chemical analysis reveals that the dark lines are made primarily of carbon, along with bits of silica.

DETER-WOLF: A composition most likely collected around the edge of a campfire.

STAAB: So what kind of depth?

Less than a millimeter.

You can feel the skin give.

STAAB: Just a little tiny pop.

DETER-WOLF: That's moving through that epidermis, yep.

STAAB: I thought it would be a little bit easier, but it takes hundreds and hundreds of punctures to actually get a solid line.

I am using the exact same stabbing technique with a brush on the model.

Looking at how difficult it was to create those tattoos on pigskin, imagine the pain that tzi had to go through when he had his tattoos made.

I wouldn't get a tattoo that way.

NARRATOR: So why would tzi endure this painful process not just once, but dozens of times?

DETER-WOLF: We generally agree that tzi's tattoos don't seem on the whole to be decorative or symbolic.

NARRATOR: For Aaron and other experts, a key clue to understanding the purpose of the tattoos could be where they've been placed.

DETER-WOLF: A number of tzi's tattoos seemed to correspond to areas where he suffered from ailments or injuries.

He had arthritis in his lower back, and there are tattoos on his lower lumbar area.

He had arthritis in his right knee; there are tattoos on the back of his right knee.

He had arthritis in his ankles; there are a number of tattoos around both his right and left ankles.

Most recently, this new set of tattoos is located on his lower right abdomen.

Among the many ailments that he suffered from was gallstones and whipworms in his colon, and this is a place that is very close to those areas and could potentially have been used to treat the pains he was experiencing.

NARRATOR: Tattooing the skin to alleviate pain has been the practice of many cultures.

DETER-WOLF: There are therapeutic tattoo traditions that have been documented all across the world: in India, in Southeast Asia, in North America, in the American Arctic.

NARRATOR: tzi's tattoos are the earliest direct evidence of this ancient tradition.

But the tattoos may not have been the only medicinal treatment tzi relied on.

In the woods of Upstate New York, archaeologist Patrick Hunt is tracking down wild mushrooms.

With the help of David Work, an expert in fungi, they're hunting for two varieties-- the same ones that tzi carried with him 5,300 years ago.

This is very much like the forests that tzi would have known in the Tyrol, where you've got mixed deciduous forests.

Wow, that's a beautiful example.

I can probably roll this over.

Maybe not.

If you're carrying two different mushrooms, you must have a pretty good idea they address different functions.

NARRATOR: One mushroom, known as tinder fungus, is often used to start fires.

When dried, it ignites easily and burns for a long time.

The other kind of fungus, which tzi carried on leather straps, is called birch polypore.

I'm gonna harvest this one.

NARRATOR: Most believe tzi was carrying this particular mushroom for another reason.

This white section here.

NARRATOR: Its antiseptic power.

HUNT: Take this mushroom, peel off the spore layers, and you can put that directly on a wound.

It's antibacterial, it's antiviral... WORK: Here, I have a cut there.

We'll put that there.

And you can actually tie it around with a piece of grass.

Band-Aid.

You don't need bacterial agents because it's got it in the mushroom.

It's already there.

Pretty cool.

NARRATOR: In addition to the topical treatment, tzi may have ingested the mushroom as a kind of Stone Age pain killer.

The peculiar thing is, it has the exact properties that act as remedies to what tzi had wrong with him.

It's been used in modern periods for some of these same functions, but tzi is the oldest case on the record for anybody knowing this.

We thought that this was a relatively modern discovery.

Obviously, it's been around for a long time.

NARRATOR: As tzi continues to challenge scientists and historians to revise their picture of the past, Gary Staab is facing his own challenge in the reconstruction of the mummy's body.

Gary knew it would be a problem ever since his day in the freezer: the Iceman's damaged hip, perhaps mauled by an animal scavenger after tzi's death.

EGARTER-VIGL: It's clear that the animals go to this part of the body.

Scavenging.

Because it's a big attraction for the animals.

STAAB: The hip is very, very complicated.

In fact, it's almost as complicated as making the entire mummy on its own.

NARRATOR: While Gary's studio team makes hundreds of simulated tendons from natural fibers that are frayed and dipped in paraffin, Gary builds tzi's ravaged backside.

STAAB: Because included in the complexity of this, there's dried muscle overlaid by tendons, then you have frayed tendons up against bone, the bone itself, the cancellous bone or the bone marrow inside of the bone that's fractured and torn apart, and then you have the soft tissues that overlay the bone on this side, you've got lower bowel intestine that's exposed and broken with bowel stomach contents inside of it, and then you have fat deposition in here.

So just this section alone has that many different finishes that have to be replicated, so this is by far the most complicated project I've ever worked on.

NARRATOR: It will take weeks to sculpt the Iceman's injured hip.

Meanwhile, scientists continue to search for tzi's true identity, investigating perhaps the most revealing evidence available: Iceman's genetic code.

CARLOS BUSTAMANTE: Genetics is giving us insights that we cannot get through any other means.

NARRATOR: The genetic blueprint of every living thing is written in DNA.

It's made of four chemicals, abbreviated as A, C, G, and T. These four letters, in a twisting double helix, are arranged into 23 pairs of chromosomes within each cell.

This is our biological code containing all the information to build and run our bodies.

tzi was one of the first ancient Europeans to have his entire code, or genome, analyzed.

It provided detailed clues to his appearance and health.

If you look at a particular gene on chromosome 15, it's the gene that most likely determines eye color.

If you see a pair of Gs at this position, that likely means that the person has blue eyes.

Whereas in the case of tzi, we see an A from both parents, and so that likely means that he had dark-colored eyes.

NARRATOR: On another chromosome, number 12, two Ts indicate that his hair was also dark.

Other chromosomes reveal new details.

tzi had blood type O.

He even had a predisposition for arteriosclerosis-- heart disease, often assumed to be associated with our modern lifestyle.

The team also found DNA fragments from the microbe that causes Lyme disease, making tzi the earliest known case.

But what about his origins?

Who were tzi's ancestors?

BUSTAMANTE: The very cool thing about DNA is that changes in DNA literally make us who we are.

The material that we inherit from our mom and our dad links us to all of our ancestors, and by comparing DNA across individuals in populations, we can get a very rich picture of our ancestry: who are we related to, where did they come from?

NARRATOR: Finding answers is especially important because tzi dates to around the time when prehistoric Europe was undergoing major changes, as the ancient hunter-gatherer lifestyle was gradually displaced by farming.

BUSTAMANTE: tzi comes from an incredibly important period in European history, where we go from hunter- gatherers living in Europe to the widespread adoption of farming.

Because it's a transitional time period in which tzi lives, there are huge life ways that converge, whether people are hunter-gatherers or whether they're early farmers.

He's in transition.

His culture's in transition.

NARRATOR: 45,000 years ago, modern humans first began arriving in Europe.

They were hunter-gatherers, foraging plants and hunting wild game.

Then, about 7,000 years ago, everything began to change.

People in Europe began to cultivate crops for food.

And by about 5,000 years ago, the hunter-gatherer culture had almost completely disappeared from the continent.

It is one of the most revolutionary transformations in human history.

Where does tzi fit into this changing landscape?

Did he come from a group of ancient hunter-gatherers who still lived in pockets throughout Europe?

Or were his people farmers living a more settled life in the foothills of the Alps?

Scientists turn to tzi's pre-historic artifacts for more insight.

HUNT: When you excavate or find someone who died 5,000 years ago, usually, all you have left are the bones.

What is so fantastic about tzi is that because he was found in a glacier, because he was frozen in time for 5,000-plus years, everything survives: his clothes, his tools.

NARRATOR: Among the items recovered from the glacier were a fur hat, patchwork leggings made of leather, deerskin shoes stuffed with hay, a six-foot longbow, a quiver that held over a dozen arrows.

HUNT: If you want an arrow shaft, you want the woods that he chose, cornel and viburnum.

They grow very straight, they're easily harvested, they're fairly prolific.

NARRATOR: His expertly made weapons seem well suited for a man who hunted for his meals.

But other objects paint a different picture.

tzi's finely crafted copper ax, one of the oldest metal tools ever found in Europe, points to a more advanced society-- one based on farming.

Could the Iceman's DNA help solve the mystery and determine whether tzi's people were hunter-gatherers or farmers?

To find out, researchers focus on mutations in the DNA, random mistakes that can occur when the billions of chemicals that make up our genetic code-- all those As, Ts, Gs, and Cs-- get copied.

BUSTAMANTE: The human genome is three billion base pairs long.

Every once in a while, you get a mutation, and that mutation sometimes ends up spreading.

NARRATOR: These mutations help create specific patterns of genetic variation in our DNA inherited from our parents.

The closer two people are related, the more of these patterns they'll have in common.

So whose DNA does tzi match best: the hunter-gatherers or the farmers?

BUSTAMANTE: The only way to get at that was to have other ancient samples from known farmers and known hunter-gatherers from across Europe across different points in time.

NARRATOR: They found the sample DNA in the bones of dozens of ancient people excavated from archaeological sites all over Europe.

Some samples go back 45,000 years, when hunting was the only way of life.

Other samples were from 7,000-year-old farming sites.

And the result?

tzi's DNA is a close match to that of ancient farmers, not hunter-gatherers.

BUSTAMANTE: It became pretty clear that all of the individuals that we had labeled archaeologically as farmers were closest to tzi.

NARRATOR: tzi's DNA reveals that he was descended from farmers who were in Europe nearly 2,000 years before he was born.

What's more, the same DNA patterns show up in even older bones found in some of the earliest known farming sites in the world, in what is today Turkey.

This suggests that farmers migrated to Europe from Turkey, filling much of the continent.

Eventually, they pushed aside most of the hunter-gatherers and their DNA.

So where is tzi's DNA now?

Could he have distant relatives alive even today?

Comparing his genome to modern DNA samples from all over Europe would provide the answer.

BUSTAMANTE: Who tzi really was genetically surprised us.

When we started analyzing the ancestry of tzi, we figured, "Ah, he was probably Italian."

Wrong-- didn't cluster with the Italians.

Maybe he's Austrian?

Wrong-- he didn't cluster with the Austrians.

Eastern European?

Wrong.

North African?

Wrong, wrong, wrong.

So where's this guy from?

And it turned out, much to our surprise, that his closest living relatives were on the islands of Sardinia and Corsica.

Totally unexpected.

NARRATOR: Does this mean that tzi was Sardinian?

Not necessarily.

Most likely, 5,300 years ago, when the Iceman was born, most people in Europe, including Sardinians, carried similar patterns in their DNA from the early farmer immigrants.

But over the last 5,000 years, Europe has seen wave after wave of new immigrants, adding new patterns of DNA to the mix.

Except on the isolated island of Sardinia.

There, ever since the early farmers arrived, the inhabitants and their DNA pattern have stayed relatively stable.

BUSTAMANTE: This wave of farmers that swept through Europe made it to Sardinia and stayed there as a genetic snapshot of what that wave of immigration looked like.

NARRATOR: This makes today's Sardinians tzi's closest living relatives.

Over the past five months, here at Gary's studio in Missouri, the Iceman has undergone a complicated transformation.

If they look at this and they believe that it's real, then I've done my job, and we want only tzi to be the final product.

It's just about tzi.

NARRATOR: Before the model is finished, its accuracy will be put to the ultimate test.

So good to see you.

NARRATOR: When Albert Zink, who oversees the institute for mummies and the Iceman in Italy, comes to examine Gary's work.

STAAB: I'm absolutely petrified that he's here to see this because he is the person who is the most familiar with the mummy.

My goal is to have him for one second be fooled that maybe he's actually looking at tzi.

I have to tell you something, it's really good.

It's a really good work.

I'm really very impressed.

It's really amazing.

That's good.

Wow, wow.

ZINK: Some moments, I felt that the mummy's outside of his freezer, it's too dangerous.

But then I realized it's the replica.

You managed to give him this kind of expression that you still can feel somewhat that this was a human being, somebody who lived very long ago.

It's really a masterpiece.

This is great for scholars because with this replica, you can really explore in much more detail.

In combination with all the other data we have, I think this will bring us also a step forward in our research.

NARRATOR: With Albert Zink's approval, the time has come for Gary to share the replica with the world.

All right.

NARRATOR: He's brought tzi to New York's Cold Spring Harbor Laboratory, one of the world's foremost genetic research institutes.

For Gary, it's like dropping a child off at the first day of school.

STAAB: I'm a little bit nervous.

It's been a really long road, and it's a lot of work culminating with this day.

NARRATOR: For many years, the director of Cold Spring Harbor was James Watson, co-discoverer of DNA's double helix.

It's remarkable.

JAMES WATSON: It was very exciting to get DNA from 5,000 years ago.

NARRATOR: tzi could never have known that how he lived and died would intrigue and inspire future generations.

BOY: It looks like he's looking at you.

NARRATOR: Like these students, some of whom have been studying him for years.

tzi is a great example of how DNA can help us learn about the past.

He's awesome, coolest dead guy in the world.

BUSTAMANTE: What's incredible about the tzi story is that as technology's gotten better and better, it's the gift that keeps on giving.

We can keep going back to the sample, and it yields new mysteries and new insights into both human history and into tzi himself.

NARRATOR: tzi was a man on the move until an arrow ended his journey through life.

But his death on the mountain would ultimately take him much farther than he could ever have imagined, and make him one of the most famous and fascinating humans who ever walked the earth.