captioning funded by cbs and ford-- built for the road ahead. >> pelley: tonight on this special edition, "60 minutes" presents "into the wild." good evening, i'm scott pelley. welcome to "60 minutes presents." if you could go just one place anywhere on the planet to see the most spectacular wildlife you'd want to head east to catch a sight that comes around every year but for only a short time.

millions of animals on an endless march of life and death and rebirth. on earth and we thought you should see it now because there's no guarantee it will be around forever. >> elephants communicate in a complicated, sophisticated language that scientists are trying to decipher and compile into the world's first elephant dictionary. >> there are protest calls. [elephant roars] and newborns have a very high cry. when you hear it, you know it's a very, very young calf. [crying] >> these fearsome noises are actually elephants greeting one another. glad to see you. come a little closer. >> stahl: the movie "jurassic park" was the story of a dinosaur red roax gone wrong,

and to the rescue came paleontologist alan grant. you consulted on that. >> i did. >> stahl: and that guy was you. jack horner is the real-life alan grant, a prominent paleontologist who believes his team has made one of the most dramatic dinosaur discoveries yet, and it wasn't just bone. >> you move the bone away and there were blood vessels and i was like shocked. [ male announcer ] humana and walmart are teaming up to bring you a low-price medicare prescription drug plan called the humana walmart-preferred prescription plan.

it's a new plan that covers both brand and generic prescriptions and has the lowest-priced national premium in the country of only $14.80 per month and in-store copays as low as $2. when you could save over $450 a year, you can focus on the things that really matter. ♪ go to walmart.com for details. sleep is here, on the wings of lunesta. and if you wake up often in the middle of the night... rest is here, on the wings of lunesta. lunesta helps you fall asleep and stay asleep, so you can wake up feeling rested. when taking lunesta, don't drive or operate machinery until you feel fully awake. walking, eating, driving, or engaging in other activities while asleep, without remembering it the next day, have been reported. abnormal behaviors may include aggressiveness, agitation, hallucinations or confusion. in depressed patients, worsening of depression, including risk of suicide, may occur.

alcohol may increase these risks. allergic reactions, such as tongue or throat swelling, occur rarely and may be fatal. side effects may include unpleasant taste, headache, dizziness and morning drowsiness. ask your doctor if lunesta is right for you. get lunesta for a $0 co-pay at lunesta.com. sleep well, on the wings of lunesta. good evening, i'm scott pelley. welcome to "60 minutes presents." during this past year, we've had some great adventures into the wild. and tonight, we're going to

bring you along on some of our favorite trips. we begin with "the great migration." if you could go just one place anywhere on the planet to see the most spectacular wildlife you'd want to head east to catch a sight that comes around every year but for only a short time. millions of animals on an endless march of life and death and rebirth. we'll save most of the superlatives for the pictures because you might agree this is one of the greatest shows on earth. we thought you should see it again now, because there's no guarantee it will be around forever. there was a time when epic migrations were common-- millions of buffalo in north america, for example. but today, to see what that must have been like, you have to travel to east africa. here, in late summer, more than a million wildebeest cross the volcanic plain of the masai mara in kenya, pushing through one of the most awe-inspiring wildlife habitats on earth-- nearly everything africa has to offer,

all in one place. the dry season is moving the herds, concentrating them where there is still grass and water. it's a march of 350 miles up from the serengeti national park in tanzania to the masai mara national reserve in kenya and back again. american scientist robin reid was hooked the very first time she saw it as a student. she's on the faculty at colorado state university, and has spent decades studying the animals and the masai people who share the land with the mara migration.

>> robin reid: we don't have migrations anymore this large. so this is the only one that stands by itself that is this large. now, if you're talking about butterflies or you're talking about birds, you're talking about, you know, smaller animals-- absolutely. you easily get up into these kinds of numbers. but as far as big animals, you know, that are walking long distance, you know, this is the one. >> pelley: this is the last one on earth. >> reid: yep, the last one on earth that is this large. >> pelley: "wildebeest" is dutch for "wild beast," which may refer more to its appearance than any ferocity. it's a relative of the antelope, but it's unlike anything you've ever seen. they call lions "regal" and elephants "majestic." i wonder what you'd call a wildebeest? >> reid: ( laughs ) i think they look insane. their horns are kind of, you know, this way and that. and then they have these big shoulders, and why in the heck is that? and they're a funny color. you know, they're not pretty. and they've got a long tail. you know, they're... they're put together in pieces. >> pelley: well, somebody once said it looks like an animal that's made out of spare parts.

>> reid: and that's very apt. >> pelley: along with the wildebeest, there are hundreds of thousands of zebra, nearly half a million gazelles, and all of them crossing the territory of predators, including lion... hyena... this cheetah that we found with her three newborn cubs... and the biggest predator of them all-- crocodiles that patrol the mara river, which cuts right through the migration route. this is easily the most dramatic point in the entire year-long migration. there comes a time that the wildebeest and their calves have to cross the mara river. you can't believe how big these crocodiles are. one of them is at least 15 feet long. but the wildebeest have to come over in order to feed, and the

crocodiles know that. a wildebeest may go through ten migrations in its lifetime. and to see them hesitate at the bank, it's as though many of them knew what was coming. first, two wildebeest scramble across. the next group takes the plunge right into the waiting crocs. the big croc strikes and has the wildebeest's horns between its jaws. a second crocodile attacks... then a third... a fourth... and a fifth. now, it's a struggle to find

enough water to pull the wildebeest down to drown. in the few days that it takes the herds to cross the river, the crocs will bring down enough food to last for months. once the wildebeest see where the crocs are, the herd runs upstream and surges across by the hundreds. no one can say how long this migration has thrived, but on the mara river, we began to see evidence that its future is not a sure thing. usually, the wildebeest swim across, but now the river is very low. could what has happened to other migrations in the world happen here? >> reid: of course. of course, absolutely.

the thing i'm most worried about for the future is the... the mara river and the amount of water in it. it's just the... you know, kind of the main artery of the... of the ecosystem, and it's very important. >> pelley: this is that artery that robin reid is talking about, and the best way to see it is from the air. the mara river rises in a place called the mau forest, and it meanders about 250 miles or so down to lake victoria. the masai tell us that there is less water in the river now than at any time they can remember. and if the mara river went away, what impact would it have on all this? >> reid: we're not absolutely sure. but in the dry season, it's the only thing that flows. and so if that water went away, then the wildebeest population would collapse. >> pelley: collapse? >> reid: yes. >> pelley: what do you mean by collapse? >> reid: you know, i don't actually know if there would be very many left, actually.

not just the wildebeest-- it would be many of the other species that require water. >> pelley: you would lose hundreds of thousands of these animals? >> reid: oh, yes, absolutely, absolutely. in fact, the estimates are-- and you know, this is a guess-- is that if the river were to dry up completely, okay, in the very first week after it dried up, we'd lose about 400,000 animals that would die. >> pelley: in a week? >> reid: in a week, yes. and, you know, maybe that's an overestimate, but even if it's in a month, that's a lot. >> pelley: we wanted to find out why the mara river seems to be drying up, so we headed north to its source, the mau forest. the first thing you notice are wheat fields where the trees used to be. and beyond the expanding farms, we headed toward smoke on the horizon. the trip brought us here. we're about five miles from the mara river. this isn't a wheat field yet, but it soon will be. what happens before the forest becomes a wheat field is that charcoalers move to the area and

cut down the trees to make one of the principal fuels for cooking. the mau forest is falling to a growing population that's trying to make a living off the land. for centuries, the mau has been a sponge, holding and releasing waters into the river. to scientists, the equation is simple-- if there's no mau forest, there's no mara river, and that means no migration. now, saving the mau forest has become a crisis in kenya, pitting the government against its own people. the government has forcibly evicted as many as 50,000 settlers from the mau. we saw it in the village of nkaroni, which was settled in the forest more than 30 years ago. the kenyan government, back in the 1990s, even gave some of the villagers title to the land. it says "nature of title: absolute."

( applause ) you take it to mean absolute. well, not exactly. a new government has turned on them. now, it says, to save the forest, villages like this have to go. in 2005, the government sent security forces to burn homes, schools and churches. but still, the people refuse to leave. >> ( translated ): we will stay. we will not go anywhere. if they want to kill us, they kill us. >> pelley: you would die right here? >> ( translated ): yes. >> pelley: the villagers in the forest don't see why their families should be uprooted for a wildlife refuge they've never seen. but we found a different story down river in the mara itself, where the growing population of masai has been willing to compromise. >> dickson kaelo: the population is a wild problem. it's growing, and its growing everywhere.

>> pelley: dickson kaelo works for a non-profit foundation that's paying the masai to turn over management of their land to a wildlife conservancy. >> kaelo: many of the families, before the conservancy started, were very poor, and quite a number of them now are able to survive and diversify away from just keeping cattle. >> pelley: the masai had been expanding their farms and grazing cattle near the migration routes. now, the conservancy manages their land for wildlife, tourists pay to see the wildlife, and the masai get a cut of the profits. families we talked to say they bring in an extra $200 a month, enough to send the kids to school. so this is all part of the conservancy? kaelo has brought nearly 300 square miles under management, and that's growing. >> kaelo: i think the children of our children of our children would like to experience the migration. it doesn't matter whether they are living in china or in the far east or in america, they would like to know that the migration is still continuing.

>> pelley: as the wildebeest moved out of the masai mara, we could see the beginnings of next year's spectacle. the elephants were raising their calves, and that cheetah was feeding her cubs on a gazelle she'd killed. cheetah cubs chirp like birds. and if they survive, they will still be with their mother when the wildebeest come around again. this perpetual cycle is a robust force of nature. but with the mara river running low and man crowding the route, no one can be certain how many turns are left for this, the last spectacle of its kind. we'll be back in a moment with

"the secret language of elephants." >> cbs money watch update sponsored by: >> mitchell: good evening. one analyst is predicting the east coast blizzard could cut post-christmas shopping by 50%. also airlines cancelled more than 2,000 flights. gas hit an average of $3.04 a gallon, up six cents in a week and 18 cents in a month. the movie "little fockers" won at the box office. i'm russ mitchell, cbs news. for.

>> pelley: for two decades, a group of wild african elephants has been watched over, studied and protected by their own guardian angel, an extraordinary american scientist named andrea turkalo. andrea's own story is pretty amazing, but as bob simon discovered, not nearly as compelling as the insights into elephant behavior that her research has revealed,

especially when it comes to the secret language of elephants. elephants communicate in a complicated, sophisticated language that scientists are trying to decipher and compile into the world's first elephant dictionary. when we heard that all of this is happening in one of the most magical places on earth, a remote clearing in central africa where forest elephants-- the rarest, most mysterious, and most threatened member of the species-- congregate, well, we simply had to go. >> simon: the sangha river flows through the congo basin, along the border between cameroon and the central african republic, in the second largest rain forest on earth. this remote corner of the world is the place andrea turkalo, a field biologist from taunton, massachusetts, has called home for nearly two decades. andrea lives in a compound that

she and a group of pygmies built from scratch. the pygmies help her run the place; commuting to her job is a hike. the last couple of miles took us through some interesting terrain. >> andrea turkalo: okay, now we're going to enter the forest. and the advice i like to give everyone at this point is to stick together. >> simon: stick together? >> turkalo: yeah. because if we happen to run into elephants, we should all stay together and move in the same direction so we don't confuse them. >> simon: we don't want a confused elephant. a confused elephant could be dangerous. fortunately, running into one on the trail is rare. so who made this trail, andrea? >> turkalo: this was made by hundreds of years of elephant traffic in this forest. >> simon: elephants made the trail? >> turkalo: yeah, i mean, if you look at their feet, it's obvious. they... you know, they do a lot of road work. >> simon: the elephants have stomped out the equivalent of a vast interstate highway system. it took us past giant teak trees, through a thick primordial forest. andrea has hiked this trail twice a day for nearly 20 years. where does it go? we could hear something before we could see anything.

suddenly, the trail ended, and right before us was an opening called the dzanga clearing, and more than 50 forest elephants. the setting was extraordinary-- straight out of "jurassic park"-- tranquil, aside from an occasional roar. ( elephant squeals ) andrea, do you remember the very first time you saw this place? >> turkalo: yeah. it was in the late '80s. and i actually slept here. >> simon: slept here? >> turkalo: yeah. and i slept on the ground in a tent. and all night, there was this symphony of elephants. and when i woke in the morning, it was like i had landed in paradise. >> simon: the clearing is a watering hole, a spa, and a sanctuary, a place where elephants take their time, the measured, graceful pace of the largest land animal on earth. they come to the clearing for the minerals, which they can't seem to get enough of.

it's a place where elephants play. these elephants are playing, sort of amateur wrestling for pachyderms. nobody gets hurt. kids fall and get up, the way kids do. this elephant is giving himself a massage, a tree massage. here's one trying to hide, unsuccessfully. all this, and so much more, observed by andrea and others, day after day. >> turkalo: it's been now 19 years that i've been observing this particular population of elephants. >> simon: it's a very long time? >> turkalo: yeah, it is a long time. but it takes a long time to know elephants. >> simon: when andrea first came here, she knew almost nothing about forest elephants. today, she's the world's leading expert on them. from an observation deck on the edge of the clearing, she collects scientific data for cornell university and the wildlife conservation society. she watches elephants almost every day, for hours, counting their numbers, monitoring their health, and observing their

social behavior. what are the basic differences between the boys and the girls? >> turkalo: females and their young stay together for longer periods of time. as you can see, these groups are made up of adult females and their young. and bulls tend to leave their groups early and be solitary. but they occasionally meet up with their families and speak to each other. >> simon: but the boys go off on their own and just sort of drop by now and then? >> turkalo: yeah. they like adventure. ( laughter ) they don't like the group life. >> simon: are there other ways in which elephants are like us? >> turkalo: the females tend to be... like to be courted by older, experienced males. >> simon: uh-huh. they don't like the young ones? >> turkalo: no, the young ones want to get to the point too quickly. ( laughter ) ( elephant sounds ) >> simon: now, what are they making noise about right now? >> turkalo: that's the penelope family. and it's their way of saying hello. >> simon: andrea knows it's the penelope family because she named them and nearly a thousand other elephants. she also recognizes them by their voices. voices researchers are trying to translate into what could someday become an elephant dictionary.

i find this elephant dictionary you're compiling exceedingly fascinating. i mean, how large a dictionary will it be? >> turkalo: we don't know. we have to really know a lot more about the behavior of these animals to sort of sort out these different vocalizations and what they mean. >> simon: andrea's expertise brought her to the attention of cornell university. peter wrege, a behavioral biologist from cornell, says the dictionary is still in its early stages. >> peter wrege: we're in kindergarten. we're just learning the very first few words. and andrea is going to help us put those words together. >> simon: and you say we're in kindergarten now? >> wrege: yes. >> simon: are we in the process of compiling the child's dictionary? >> wrege: even an infant's dictionary. ( laughs ) it's a very, very complex process because we can't ask the elephant, "what did you just say?" >> simon: but they can match elephant sounds with behavior they can see, and classify those sounds into distinct categories.

can you tell me what some of them are? >> turkalo: well, there's these low frequency rumbles. it sounds like a big cat purring. and those are the... those are the vocalizations that help keep groups in contact with each other. there are protest calls. in newborns, you have a particularly very high cry. and when you hear it, you know it's a very, very young calf. ( elephant sounds ) and some of these big bulls, when they go into musth-- which is this sexual state-- they make a special rumble, which is very low and very pulsing. ( elephant sounds ) >> simon: most days, andrea works into the evenings, compiling data and exchanging information with researchers back in the u.s. via the internet, which she also uses to stay in touch with home. >> this is n.p.r. worldwide from washington. >> simon: the archive of elephant behavior and sound she's created is amazing and surprising.

( elephant sounds ) these fearsome noises are actually elephants greeting one another. "glad to see you." "come a little closer." ( elephant sounds ) these are sounds of annoyance. the big bulls are telling the youngsters to hit the road. back in 2000, andrea filmed the death of a baby, and the traumatized cries of the other elephants. these elephants kept poking the body over and over, frantically trying to coax the baby back to life. then, the elephants formed a procession that filed past the body. >> turkalo: they'd feel it or they'd smell it, and then they'd vocalize. it was like a funeral procession that went on three or four days. >> simon: must have been an amazing sight. >> turkalo: they seem to recognize death, and it upsets them. it sort of brought home how emotional these animals are. >> simon: but it turns out that these vocalizations are just a small fraction of the sounds elephants make.

until a few years ago, scientists had no idea that most of what elephants are saying can't be heard by the human ear. >> wrege: the base of their vocalization is infrasonic. in other words, the frequency on which their call is built is below what we can hear. >> simon: the elephants use those low sounds to find one another in the dense forests where they spend most of their time. >> wrege: elephants are using very low frequencies in their vocalizations, which travel far. this... >> simon: how far? >> wrege: at least two or three kilometers. >> simon: no kidding? more than a mile? >> wrege: yes, and... >> simon: an elephant standing here can communicate with sound with an elephant more than a mile away? >> wrege: yes. ( bell rings ) >> simon: 6,000 miles away in upstate new york, at a lab at cornell university, researchers are listening to everything from the sound of hummingbirds... to the sound of whales. the elephant listening project grew out of an accidental

discovery made by its founder, katy payne, one of the world's leading experts on elephant communication. >> katy payne: i love animals, right? so i went to the zoo. >> simon: the elephant cage? >> payne: the elephant cage, and i began to realize that i was feeling a throbbing in my ears and in the air that i couldn't really explain. and i said, "you know, do you suppose that elephants are making sounds that are below the pitches that i can hear?" and we recorded for a month and, lo and behold, we found that elephants had a great many sounds that people didn't know about. >> simon: she gave us examples of sound that we can hear. ( elephant sounds ) >> payne: a sound which i interpret generally as "everything's in order." >> simon: "everything's okay with the world." >> payne: "everything's okay." >> simon: but then, how do you discover the meaning of these sounds? >> payne: you just watch and

watch and watch, and record and record and record, and keep the two together. >> simon: which brings us back to andrea. once or twice a year, she visits cornell with her latest recordings. and you're giving the material with which they work? >> turkalo: yes. this is a scene we filmed on the first of may, the first birth we've witnessed in 19 years. >> ooh! look at this. >> simon: after ooh-ing and aah- ing over the new baby, as anyone would, the scientists get down to the business of figuring out what the elephant sounds mean. >> i'm betting that these two calls are the same individual. >> turkalo: yeah. >> simon: figuring out which elephant is talking, where it's located, and what it's saying has been a big challenge. researchers initially strung nine acoustic recording devices around the clearing. as the sound reached each recorder at a different time, they could pinpoint the location of the speaking elephant. picking up sounds too low to hear was another challenge, but recording the sounds normally and playing them back faster was a revelation. for example, the clearing at night sounds like this.

( cricket sounds ) played back three times faster, this is what the clearing sounds like. ( fast-paced squeaking ) you can hear the elephants' rumbling calls. but to figure out what the calls mean, the cornell team spends more time looking than listening. using these computer-generated spectrograms, they can see the low-frequency sounds. >> wrege: and then, we can actually visually look at the calls. >> simon: and what does this visualization tell us? >> wrege: it tells us that there's incredible complexity. many of their calls are actually similar, in some ways, to human speech. >> simon: peter, does all this research into elephant sounds have any practical purpose? >> wrege: we're using sound recordings to monitor forest elephants because they are so difficult to see. and this becomes more and more critical because their population is threatened.

so, knowing where the animals are gives us a way to begin attacking what has to be preserved or where do we need to put more protection. >> simon: protection, because poaching has become almost epidemic. it's estimated that, annually, 10% of dzanga's elephants are killed for their ivory. andrea works closely with dzanga's armed guards, but so far, their efforts have not stopped the slaughter. do you see it as your personal responsibility to protect the elephants here? >> turkalo: i've made it my personal responsibility. for me, if i've been given this great privilege to study this particular population of elephants, i think my priority is to protect them. otherwise, i have no right to study them. ( elephant sounds ) >> simon: excuse me, we have a vocalization. >> turkalo: that's a protest. >> simon: a protest? >> turkalo: that's somebody who's probably being refused something by its mother. >> simon: baby elephants protest in a rather loud fashion, don't they? >> turkalo: yeah, yeah. they're just like little bratty children. ( laughter ) >> simon: andrea believes if she weren't here, the clearing would

become a killing field. it's clear that, in a very pragmatic sense, you are saving the elephants. >> turkalo: but in another sense, they've saved me. i have something very important in my life to do. and i think a lot of people don't get to do that. >> simon: andrea plans to stay here at least another 15 years. and as night falls over her clearing and fishermen float gently down the sangha, you can hear the crickets. what you can't hear are the elephants, but that doesn't mean they aren't talking. >> pelley: when we return the story of a 68-million-year-old tyrannosaurus rex. >> hello, everyone. welcome to the cbs sports update. i'm james brown in new york. new england received the top seed and home field advantage in the a.f.c., while chicago has the inside track for the second seed in the n.f.c.

jacksonville's loss put the jets into the playoff. baltimore also clinches a playoff berth. indy holds the inside track in the a.f.c. south. the giants' loss gives philly the n.f.c. east. st. louis will play seattle next week for the n.f.c. west. for more news and scores, log on to cbs intorts.com. -- cbssports.com. and now i'm also taking lipitor.

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>> pelley: there is something about dinosaurs that captures the imagination-- giant, mysterious animals that roamed the earth for millions of years, now gone forever. all they've left us are their fossils, the dried-out mineral remnants of the creatures they once were, with the organic material that gave them life long gone. or so everyone always thought. that is, until b-rex, a 68- million-year-old tyrannosaurus rex who was dug up and named by a paleontologist from montana state university, who, as lesley stahl discovered, has an unorthodox approach to dinosaurs which may be changing the whole dino ballgame. >> stahl: think dinosaur, and most of us think this-- the 1993

classic film "jurassic park," with its dinosaur resurrection experiment gone wrong, and its embattled hero, famed paleontologist alan grant. you consulted on that movie. >> jack horner: i did consult on all those movies. >> stahl: and they said that the guy, alan grant, was you. >> horner: yes, well, fortunately, he didn't get eaten. >> stahl: meet jack horner, the real-life alan grant. he's one of the most prominent and controversial paleontologists in the country, a dyslexic macarthur foundation genius who never finished college, and who says he doesn't care why dinosaurs went extinct. to him, the important part is how they lived. >> horner: i'm trying to figure out the biology of dinosaurs and what they were like as living creatures. >> stahl: you want to know what their behavior was, how they treated their young? >> horner: i want to know everything we can know about them, and make one if we can. >> stahl: make a dinosaur?

the things jack horner says make him a maverick, but the finds he's made, including more t. rexes than anyone else in the world, make him a legend. >> horner: see if you can tell me what these are. >> stahl: oh, my gosh. are these teeth? >> horner: yes. >> stahl: look at that. and not just any teeth-- the teeth of the oldest t. rex ever found. >> horner: this little pocket right here in the teeth is where the next tooth sits. dinosaurs replace their teeth throughout their life, and t. rex replaced all of their teeth every year. >> stahl: but horner is most famous for discovering a kinder, gentler side of dinosaurs. here in the badlands of montana, he and his team uncovered the first dinosaur nesting ground in the world, a vast landscape full of eggs, nests, and babies that helped change our image of dinosaurs. thanks to horner's influence, "jurassic park" showed that most dinosaurs were social animals who lived in colonies, and he's

found evidence they actually cared for their young. >> horner: this is the tibia, the shin bone. and this is a little less than a month old. and here, here is the same bone. >> stahl: of an adult? >> horner: of a one-year-old. >> stahl: a one-year-old. ( laughs ) horner figured out that such rapidly growing baby dinosaurs couldn't walk at first, meaning that their parents were bringing food back to them in the nest, like birds. his discoveries lent support to a then-controversial but now widely accepted theory that dinosaurs actually gave rise to modern birds. if a little kid today who studies all this in school, and they look up in the sky and see a bird and turn to mom and say, "you know, that's a dinosaur." >> horner: they're right. >> stahl: they're right. >> horner: they're right. >> stahl: jack horner told us

that birds are dinosaurs. do you agree with that? >> sean carroll: absolutely. >> stahl: sean carroll is a professor of molecular biology and genetics at the university of wisconsin. >> carroll: so, really, dinosaurs never went extinct. >> stahl: dinosaurs never went extinct. but we all think they did. >> carroll: there was an asteroid event that took out a lot of life on earth, including t. rex and all the most famous dinosaurs. but this other group, what we call birds, made it through, and of course, there's thousands of species of birds still around today. >> stahl: the dinosaur-bird connection is largely settled now, but that hasn't stopped horner from using unusual means to make unusual discoveries. and he's found the perfect partner in his protége, mary schweitzer, a professor at north carolina state who studies the internal makeup of ancient bone. she let us in on the paleontologists' trick for telling dinosaur bone from rock. you don't just look at it. >> mary schweitzer: touch your tongue to that.

>> stahl: she actually wanted me to lick it. >> schweitzer: it's supposed to stick like velcro. >> stahl: ah, ew. it did. >> schweitzer: that's bone. >> stahl: that's how you can tell? >> schweitzer: yeah, because the bone's filled with... with little capillaries. and when you put your tongue on it, the moisture from your tongue sucks out the capillaries... >> stahl: this is 80 million years old and it can do that? >> schweitzer: yeah. >> stahl: oh, my god. >> schweitzer: rocks don't do that. >> stahl: the tricky thing about schweitzer's work is that she needs to get her hands on the insides of dinosaur bones, which means literally breaking the bones apart, and sometimes dissolving pieces of them in acid. most paleontologists won't let her near their precious finds. >> schweitzer: jack is the only paleontologist out there who lets me dissolve his dinosaurs. >> stahl: dissolve his dinosaurs. >> schweitzer: yes. >> stahl: you mean ruin them. >> schweitzer: yeah. >> stahl: isn't that considered a little sacrilegious to... >> horner: yes. >> stahl: ...take one of these precious artifacts, fossils that have been in the ground for 68 million years, and crack it in half?

>> horner: we found the first dinosaur embryos, the first babies inside of eggs. and it was just from breaking the eggs open and looking inside. i mean, people had always thought that eggs were so precious, they didn't want to break them and look inside. and yet, they're like presents. you know, i mean, it's like having a christmas present and never unwrapping it. >> stahl: did you ever, though, have a moment where it was kind of heartbreaking? you know, "i'm..." >> horner: no. >> stahl: "... i'm destroying..." never? >> horner: no. glue is cheap. >> stahl: horner's practice of breaking dinosaur bones apart and sending the insides to mary schweitzer has landed the two of them at the center of one of the biggest controversies paleontology has seen in years. it started back in 2000, with a series of coincidences. a member of jack's team, bob harmon, wandered away from a dig site one day to eat lunch, and noticed a small piece of bone sticking out of the side of a 50-foot cliff. >> bob harmon: i could tell pretty much what it was from where i was sitting. it was a t. rex metatarsal.

>> stahl: how was it sticking out? you mean, it was a... here's a cliff, and it was like a... little jutting out? >> harmon: yup, exactly. >> schweitzer: he got a folding chair and he stacked it on these rocks, right there. and you can see that this is on the sheer side hill of a cliff. >> stahl: this is not possible. is he attached to anything? >> schweitzer: no, he's not. that's bob. >> stahl: jack named the t. rex "b-rex"-- in bob's honor-- and made the decision to dig it out. >> horner: this was under 50 feet of rock. i mean, this was in a terrible place. there was no road to it. there was no access to it. and so, for the next three summers, we sent out climbing crews, people that could rappel down cliffs with jackhammers. i mean, it was a horrendous undertaking. >> stahl: the site was so remote, the bones had to be lifted out by helicopter. but the giant cast containing b- rex's thigh bones was too heavy; the chopper couldn't get it off the ground. so after all that excavating, jack gave the order to cut one of b-rex's femurs in two.

now, that was heartbreaking. >> horner: no, no, not really. i mean, you get a chance to see inside. >> stahl: he shipped the bone fragments that fell out to mary schweitzer. >> schweitzer: so the first piece i pulled out, i picked it up and i looked at it. and i said, "it's a girl and it's pregnant." >> stahl: that's the first time, as i understand it, that anyone had ever been able to identify gender in any dinosaur. >> schweitzer: yes. >> stahl: mary recognized a specific type of bone called medullary bone, which female birds produce when they're about to lay eggs. no one had ever found it before in a dinosaur. it was yet another link to birds, and it meant that b-rex was definitely no "bob." so she calls you up and she says... >> horner: she calls up and says, "we have medullary bone." >> stahl: oh, now, this had to be thrilling. >> horner: yes. very exciting. and that wasn't all.

>> stahl: what happened next happened by mistake. mary put some fragments of the bone in acid to dissolve away the outermost layer of mineral. but the acid worked too fast, and all the mineral dissolved away. being a fossil, there should have been nothing left, but there was, and it was elastic, like living tissue. >> schweitzer: this is the piece. >> stahl: no. she showed us video she took under the microscope. that's really what happened? that's the dinosaur bone? >> schweitzer: yeah, without mineral, now. that's what was left. >> stahl: it looked like the soft tissue she would've expected to find if it had been modern bone. this was impossible. this bone was 68 million years old. so you see this and you think what? >> schweitzer: i didn't want to tell anybody. >> stahl: you'd be ridiculed. >> schweitzer: yes. and so i... i said to my technician, "okay, do it again. i don't believe it." >> stahl: and yet, in sample after sample, they were there-- things that looked suspiciously like flexible, transparent blood vessels.

she finally mustered the courage to tell jack. >> horner: she said she dissolved the bone away and there were blood vessels. and, you know, i was, like, shocked. >> stahl: "how could that be?" >> horner: how could that be? that's right. >> stahl: the things mary was finding inside dinosaur bones-- blood vessels, and even what seemed to be intact cells-- pose a radical challenge to the existing rules of science; that organic material can't possibly survive even a million years, let alone 68 million. mary, jack, and their team published their b-rex findings in a series of papers in the journal "science," and were promptly attacked. critics said their samples might have been contaminated, or that the supposed blood vessels were actually something called biofilm, a type of slime. but as mary showed us, she has been able to replicate her findings. these are pieces of an even older dinosaur, a well-preserved 80-million-year-old duckbill.

when she dissolved it away in acid... >> schweitzer: let's put this under the scope. >> stahl: well, look. is that a blood vessel? >> schweitzer: this is a blood vessel. >> stahl: you're kidding. >> schweitzer: you see the branches right there? look at all of them. it's so consistent, over and over and over again. we do this bone, and it comes out and i get excited every time. i can't help it. i mean, 80 million years old. >> stahl: mary published her new results last year, and while some of her critics have been swayed, the controversy still rages. and the stakes are high-- if blood vessels can survive 80 million years, what about d.n.a.? jack horner is looking. his crews are now wearing surgical gloves, unheard of in the world of paleontology where no one used to worry about getting skin cells, sweat, even an occasional spilled beer on fossils. jack is skeptical that the full dinosaur dna sequence will ever

be found, but that hasn't stopped him. he's come up with a whole new idea for his dream of making a dinosaur. > horner: the best way is just to use a modern dinosaur-- the chicken. because evolution works, birds are actually carrying ancestral dna. >> stahl: horner has written a book proposing a plan to mine that ancestral dna as a way to reverse-engineer a chicken into what he calls a dino-chicken. it may seem improbable that this is carrying dna from something like this. but when you think about it, birds, like the dinosaurs they evolved from, still walk on hind legs, most have three toes pointing forward with one in the back, and they even all have wishbones. as for dinosaur features you don't see in modern chickens, like long tails, horner's contention is they can be brought back, since you can still see them in embryos as little chicks grow.

>> horner: as the chicken embryo develops, it does develop a fairly long tail before a gene kicks on and destroys it. so if we can stop that gene, we theoretically can get a chicken to hatch out with a relatively long tail. >> stahl: so you're not saying actually change the gene... >> horner: just switching a gene on or switching a gene off. >> stahl: he says picture a chicken with a long tail, teeth, and little claw-like hands instead of wings. so, maybe there will be a dino- chicken. >> horner: i am sure there will be a dino-chicken. >> stahl: you're sure they'll be a dino-chicken? >> horner: i think we'll be able to make a dino-chicken within the next five years. >> stahl: boy, i see a new movie coming out of this. >> horner: this time, i could get eaten. ( laughter ) depression is a serious medical condition.

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