Original subtitles

dinosaurs the most sophisticated best

engineered highly adapted survival

machines ever created by nature

these guys were very successful 165

million years of evolution gives these

prehistoric Giants weapon defenses and

advanced senses able to put modern

animals to shame

now with cutting-edge imaging technology

we can go deep into a dinosaur's body

and reveal how adaptation makes them

stronger smarter

to me it's the ultimate mystery what it

allowed them to be so successful for so

long

[Music]

dinosaurs are the planets ultimate

living creatures they survived for over

165 million years the key to that

success our bodies well designed on the

outside and precision-engineered

on the inside

their advanced physiology comes down to

one thing adaptation the result of both

natural and sexual selection

over more than 10 million generations

these giants continually improve

creating one better dinosaur for another

natural selection is eliminating those

animals that are not smart enough to do

the job they need to do eliminating the

clumsy and favoring those that have the

the brainpower to accomplish these

complicated tasks

evolution means some species thrive

while others are driven to extinction

and in animals with such dangerous

armaments competition for survival can

be deadly

late spring

the Cretaceous period

[Music]

adolescence is a critical time

dinosaurs are preparing to mate

some will succeed others will fail

in Darwinian calculus you can be the

finest hunter in the land and if you

can't attract and hold on to desirable

made with desirable genes you're losing

a loser

whose genes are about to reach the end

of the line mating is serious business

with significant repercussions of male

looking females

female looking at a male what they're

doing without actually thinking it

consciously is evaluating the potential

genes over there are your genes good

ones well your genes mix with my genes

make a really healthy very competitive

youngsters

clues the males are approaching sexual

maturity about the crest on an

adolescent parecer Ovilus is now fully

developed

Triceratops horn have grown from little

stubs pointing backwards delete the

weapons pointing forward

and Tyrannosaurus Rex a snake claim to a

territory of his own

male soon-to-be adults fight for the

chance to prove they've got the right

stuff females choose carefully only the

strongest fittest or smartest males

will do

and when it comes to reproducing

something else is critical time

most big predators today breed home run

a short interval in the year actually

most animals today breed only in a short

interval a couple days their weekly to

the outstanding exception being that

peculiar predatory species Homo sapiens

for egg-laying animals it's almost

always in the late spring or summer that

way the eggs can be incubating during

the summer during the warmest part of

the year when

the climate is the most amenable to the

production of young

to know when to mate dinosaurs react to

the change of seasons in the weeks

leading up to the breeding season there

would be hormonal changes taking place

in the body of the dinosaur that are

triggered by passing time itself by the

length of the day for example

as winter recedes the days get longer

sensors in the back of the eyes respond

to change in life

transmitting crucial information to the

bridge

a signal triggers the pituitary gland to

release the hormone gonadotropin these

chemicals prepare their bodies to

produce eggs or sperm

raging hormones also trigger dramatic

changes in behavior very different

changes in males and females

with the females that means stockpiling

resources to produce the offspring for

the males that means figuring out how

they're going to beat the other males at

the game of reproduction of son

they more alert they're more visual

they're being more aggressive you're

more fights beginning the whole cascade

of social complexity which would be

really fun to watch

with hormones racing through their veins

a carnivores advanced killing tools

become even more deadly between the ages

of 15 and 18 the mortality rate for

meat-eaters like t-rex increases

fivefold

this is the age adolescent males begin

to challenge older more experienced

males

battles may start over a maid but they

can quickly devolve into a deathmatch

there's going to be some threshold some

test that the male has to pass to get

the privilege of meeting us the female

and get the privilege of reproducing

fights break out over territory bragging

rights and of course to impress females

these clashes are shows of strength it

meant to prove who has the best genes

fortunately most of the time death to

your opponent is not the goal it's all

about getting your genes into the next

generation

evolution tends to favor types of

displays between members of the same

species that are not necessarily lethal

that it becomes clear that the one who

wins that match has something better

than the other ones a healthier pattern

a more vigorous display hinting at a

better internal condition or healthy

condition one of the things that

supposed to be true in the animal

kingdom in today is that when animals

have extreme structures they do use them

as display boards as advertising boards

especially during the breeding season

weighing in at six tons Triceratops are

the street fighters of the Cretaceous

for this bruising the most powerful

herbivore of all time

evolution means getting stronger tougher

meaner and those are exactly the traits

females look for in man

Triceratops bony crow forms a defensive

shield

a strong one is a sign of strength and

power but maybe it advertises something

else as well the frill might have

evolved as a defensive measure against

predators it might have evolved as a

species recognition character

but there's no reason why it couldn't

have been taken advantage of in the

evolutionary process as sexual billboard

could a triceratops drill like a peacock

feathers be a display of Verrilli

one clue is that a change is coming the

bone that forms this shield is riddled

with a mesh worth of arteries and veins

in times of stress or excitement

hormones are released into the

bloodstream arteries in the neck white

and blood rushes to the frill

terney blood red

it's a ritualized drum

with one single goal

you'd have to demonstrate to the females

that they're the biggest healthiest and

perhaps smartest of the male's that they

have earned the right to reproduce by

proving themselves worthy earning the

right to reproduce means earning the

right to impact in the future of your

species is suspect this whole dance had

pretty much been choreographed through

their lives where they came in and then

locked horns and he started pushing when

bull meets bull there could be

potentially along in prolonged fight not

just smarting from the did snort and

pawing the ground but thrusts encounter

thrusts just kinda like an armrest

using their their horns for males with

horns four feet long six tons of muscle

and a shield made of solid bone

competing for a mate is risky business

but for a female creating the next

generation takes hard work and facing

life-or-death choices failure can mean

bringing youngsters into a brutal world

a world where they simply don't stand a

chance

during the Cretaceous dinosaurs evolved

with the most physiologically advanced

features in Earth's history a

sauroposeidon can reach 60 feet tall

towering over its surroundings ketse

Cuates is a flying reptile as large as a

giraffe and Tyrannosaurus Rex is the

most powerful carnivore to ever start

the planet

all these traits are the result of

evolution adaptation over millions of

generations but evolution is harsh and

ruthless especially for males one by one

natural selection and sexual selection

leave the weak and the timid behind most

of the males are probably not going to

be reproducing so if you're a male the

problem is making it into that small

percentage they're actually going to be

sending their genes in the next

generation evolution doesn't like losers

it only works when the best genes are

passed on to the next generation it's

the law of the jungle and the spoils go

to the victor

Darwinian cut consists of this just a

large group of females there that you

can control is one male then you're

gonna risk fighting another male the

payoff is so big if you win 20 30 40

cows that's be the payoff may be huge

for the lucky male but fatal accidents

can and do happen trying to rule the

pack can end badly very badly for a

young buck

females have their own concerns they

must prepare to bring a new generation

into the world a new generation that

needs to be a little bit better than the

last

fossil records show that dinosaurs

needed to prepare for mating early in

life

one of the things we're finding in

common for all dinosaurs is that they

started reproducing when they were still

growing and this tells us that life was

cheap in the age of dinosaurs these

dinosaurs may be young but they've got

plenty of work to do they must ensure

that they are in good health well-fed

and have plenty of nourishment for their

unfertilized eggs as these big dinosaurs

are growing up there comes a point where

they have to start putting some of the

resources not just into growth anymore

into reproduction whether a carnivore or

herbivore calories are key to be a

successful mother females need plenty of

nutrients that means high-calorie young

leaves and shoes or if you're a

carnivore more red meat without it no

eggs

females have to be stockpiling resources

big time lots of protein lots of fats

lots of calcium all those materials have

to be stored in the body so they're

available instantly to start producing

the eggs as soon as the animals made it

hormones and females stimulate the liver

to send yolk to the ovaries

when her eggs are fertilized the yolk

will provide enough nutrition to keep a

growing dinosaur embryo alive for as

long as three months

a dinosaur mother-to-be also needs

calcium for eggshells

the dinosaur eggshell is composed of

calcium carbonate just like bird

eggshells today like some crocodilian

eggs have this hard calcium carbonate

eggshell and that eggshell protects the

developing embryo

a single female sauroposeidon produces

300 to 500 eggs each season that takes a

lot of calcium a mineral and short

supply in the plants of the Cretaceous

so just how does this Leviathan the

creature requiring almost 400,000

calories a day just to survive managed

to maintain its girth and get enough

nutrients to reproduce

chowing down in springtime is crucial

that's when protein in plants is more

available and easier to digest calcium

is not very abundant in a lot of plants

and so you have to eat a lot you have to

focus on high quality foods high quality

plants the buds the shoots the young

leaves to try to get those minerals

those nutrients to build the babies

which sort of poseidon's voracious

appetite tiny amounts of calcium that up

bit by bit it's all stored in her bones

specifically medullary bone

metro-area bonus very special bone

that's laid down only by an ovulating

female and it's laid down to gathered

together calcium for calcium carbonate

eggshells that they're making during

ovulation medullary is a layer of bone

which lines the interior of leg bones it

has no structural purpose instead it's a

mobile store for calcium and other

minerals required to make eggshells once

stored in medullary bone calcium and

minerals can easily be broken down and

sent to where it's needed

so you're looking at the unfolding the

unpacking of something that starts out

as a single cell into an animal that's

almost the size of a whale and it has to

come off without a hitch in

sauroposeidon

evolution is favored something else as

well the production of a tremendous

number of eggs every year and every one

of those eggs takes resources after

mating the female sewer poseidon is now

starting to grow the eggs inside of her

and eggs are expensive their protein and

fat and calcium calcium for the bones of

the embryo eventually calcium for the

shell of the egg

a single sauroposeidon lays hundreds of

eggs each season but many are eaten

before they hatch and most hatchlings

are devoured by hungry carnivores

Tyrannosaurus Rex on the other hand has

evolved into something entirely

different

these powerful meat eaters are

intelligent and dweller they are killers

and scavengers

a female ready to pass on her genes is

on the lookout for a male with huge jobs

a powerful grip

and a mouthful of steel tough teeth

[Music]

sauroposeidon is an herbivore the

evolutionary strategy for this giant is

to lay hundreds of eggs in the hope that

maybe just one or two survived to

adulthood

to build eggs and embryos they must

consume thousands of galleries of

vegetation

Tyrannosaurus Rex is a carnivore to

produce eggs it too needs nutrients

calcium and protein

but this female doesn't get calcium from

munching on plants

she gets it by crunching phone

the bones of plant-eaters Tyrannosaur

could process a lot more of its prey be

able to digests more do you get the meat

from the marrow the the the the the

nutrients from the marrow we could even

digest some of the bone itself and

there's proof that t-rex got its calcium

straight from the bones of herbivores

t-rex turds we have coprolites

fossilized feces from Tyrannosaurus and

it shows pulverized bits a plant-eating

dinosaur phone in there so it punched

down and crunched

and the phones had swallowed all of it

and the bones made it out in digested

form out the other end of the t-rex

a female Tyrannosaurus Rex needs to

store the calcium she's building up and

like a sauroposeidon she'll store that

calcium in her medullary bone

staying strong is imperative for a

female preparing to mate

especially since compared to a man she

has far fewer chances to get

reproduction right females are born are

born with a set number of eggs within

them so that they have only a set number

of column tickets to Eternity where

males produce these by the millions

every day they produce more sperm

females only have these few eggs and

they have to invest their time their

resources within their bodies in the

development of these eggs evolution too

has prepared for this difference between

males and females one of the interesting

things about dinosaurs in general

including t-rex is that if we look at

their skeletons we often see that there

is one form that's bigger bone than the

other it turns out that those really big

ones those really massive ones that most

scary ones of all were female for a

female t-rex finding just the right mail

to deliver strong offspring to pass on

that one trait that just might give her

young the edge they need is not easy

Tyrannosaurus Rex live a solitary

existence and just a handful roam a huge

territory

as a larger the animal the smaller the

population that the surrounding

territory and surrounding animals can

support so you know actually coming into

contact males and females coming into

contact might be a rare occurrence

there's little direct competition

between males for t-rex it's more about

protecting your territory from intruders

and tracking every female in your range

I think the sense of smell would allow a

male or two to to know of an ovulating

female probably miles away a

Tyrannosaurus Rex is one of the largest

most powerful predators to ever walk on

two legs

but a male hoping to mate must be

cautious and keep his distance until he

sure the time is right the choreography

of courtship and teawrex would have been

interesting to watch the state is a

stranger male attempting to insinuate

himself with a few down there onion with

Darwinian calculus is this the type of

male whose genes we want mix with our

genes to make the next generation

a t-rex is not just huge and vicious

it's also smart courtship no death

followed a strict set of rules

the female has to perceive the right

signals from the man so they might in

time you know over span of several days

weeks start looking for one another

let's court let's get together I don't

know maybe dinner and movie for a man

t-rex when it comes to impressing the

female the female t-rex is much the same

shape as the male us ten twenty thirty

percent bigger which means stronger

which means one-on-one the females going

to win every time a lone male trying to

attract a female is definitely taking

his chances correctly breeding cues from

the opposite sex may make the difference

between life and death now if we think

about the males being you know only

two-thirds the weight of a female the

size of a female if there's going to be

any kind of an argument

the female it's gonna win

this size difference is true with most

dinosaurs but in the case of t-rex it's

extreme the risk would be if you really

make her angry she might eat you for

lunch

even for a male who's made it this far

about to be rewarded with his prize this

one final challenge can be deadly now is

in the danger zone is within the killing

zone if the females reject him they're

big and bite his head off and that's the

end of him in terms of Darwinian

calculus

but in the end despite the many risks

and hazards the strongest most well

adapted Turan asaurus rex passes on his

genes to a new generation

a generation that might just roll over

a bit stronger and made even tougher

than its parents

for males only the strongest or smartest

win the right to their prize and only

their traits will be passed on

perhaps a longer whore

a stronger friend

a bigger slashing for better hearing in

sight the smell the genes for less

useful traits eventually reached the end

of the line fossil evidence tells us

much about how dinosaurs adapt but

reveals little about what courtship for

these giants might have been like

if we imagine these big 3/4 ton

tyrannosaurs doing these mating dances

and elements it's kind of weird but one

thing we do know is that the dangers of

mating are real fossil evidence points

to serious or even fatal injuries tails

crush ribs and vertebrae fractured

skulls bitten dinosaurs have create the

next generation at their own risk if

there's going to be an attempt at mating

on the part of the male it really has to

be certain that the female is receptive

because if she's not she can say no in

quite a dramatic and indeed a fatal way

there's a reason why evolution put

females in charge when it comes to

reproduction they do the real work so

they get to decide which traits survive

and which ones simply die out

the females are really the vital link in

the chain here they're the ones that are

building the baby's butt a little bit of

sperm goes a long way so most of the

males are probably not going to be

reproducing like animals today most male

dinosaurs battle it out for the chance

to reproduce

females look for a male who can prove

he's stronger and tougher and maybe more

clever than the competition

but sometimes an evolution goes another

direction and rewards highly unusual and

very specialized traits physically

parecer alice is horn

it's useless as a weapon it's hollow and

fragile and just 1/10 of an inch thick

but as a communication device it's a

remarkably effective form of Defense

able to send out complex messages

warning of danger or distress

over more than a thousand generations

this press grows longer and the sounds

it emits grow deeper low frequencies

able to travel long distances

highly developed communication skills

become a significant evolutionary

advantage and soon enough females only

want to make with the guy with a great

set of pipes it's a sound generating

organ it can't help but generate unusual

sounds by blowing air through this tube

and because each species has a seemed

own distinct shape each species would

have its own distinct sound but just how

did evolution create this bony crest

able to produce sounds that can travel

for miles it's simple they got bigger on

the outside the tubes appear to be only

about 3 feet long but on the inside

chambers loop back and forth creating as

much as eight feet of resonance or

natural amplification parasurama's

generates resonant frequencies as low as

50 Hertz a sample most as deep as a

foghorn we can now actually model the

kinds of sounds that that resonating

chamber would make and it turns out that

their deep sound low frequency sound

low-frequency sound waves can transmit

for miles even through dense forest

these calls warn of intruders a

significant defensive advantage

but just how did evolution create a bony

crest able to produce sounds that can

travel for miles

the answer is simple repair psaropoulos

the traits that makes survival in a

savage world possible soon enough become

the very same traits that attract a mate

for a healthy male a communication

device doubles as the perfect tool for

will we be opposite sex

it's Trumble like structure going out of

the back of the head was used for making

dinosaur music during courtship the

male's would be calling during the

breeding season attempting to influence

multiple females the females are calling

to challenge the males to prove

themselves because the fundamental fact

of courtship is that males lie and

females are skeptical so the skeptical

females force the male to go through

more and more hoops and loops and hoops

to persuade the female to mate it's

called sexual selection and like natural

selection it means that females choose

traits and males that make survival of

their offspring more likely multiply

those choices over thousands of

generations and suddenly Deinonychus is

slashing claw gets sharper faster and

morally

[Music]

Triceratops horn gets longer and it

shield grouse time

and parecer alice's crest becomes more

advanced and their communication skills

better and it better prepares a female's

concern during the breeding season would

mostly be checking out the guys that is

finding which ones seem to be the

healthiest and therefore were

potentially the best fathers of the next

generation evolution perfects not only

parasurama Liz's ability to make sense

it also selects four genes that improve

the ability to hear and interpret those

sounds

various male Parasaurolophus would

presumably be making very loud very

raucous calls of a very particular sort

and a female Parasaurolophus would be

judging the quality of that call

probably its sound which may have

represented how healthy the individual

was and its ability to be precise in

terms of generating that sound because

it showed that was a creature with a

healthy mind with all the proper genes

for the Parasaurolophus

males with the largest crest to produce

the richest and lowest frequencies

sounds that can travel for miles

those same low frequency calls become

highly attractive to females

we would have to friend Parasaurolophus

competing with each other um with these

sound calls and the females probably

calling on occasion to say hey baby that

sounds really good you're the one for me

[Music]

for parecer Ovilus genetic modifications

over time give them the tools both to

pick up and emit low frequency sounds

in fact over time they evolved the

ability to send and receive extremely

low-frequency vibrations called

infrasound

each species seems to have had its own

note or series of notes and can have up

to five different species of duckbill

living in one place at one time so in

the breeding season you'd hear five

different orchestras five different

ranges of courtship now and you'd feel

for your feet too as they go into those

really deep minutes but parecer Ovilus

is the exception not the rule

for most females of the Cretaceous

finding a mate who's stronger smarter

and packs more advanced killing tools

than the next guy

is crucial but there's more for a t-rex

male surviving to adulthood most likely

means he sat some good parenting himself

no doubt he's also developed some strong

hunting skills and probably even learned

to duck when Quetzalcoatl swooped down

and tried to steal him as a chick in

other words you don't make it this far

without some good genes to pass down

but evolution isn't just about making

it's also about ensuring those valuable

eggs actually

the prehistoric world of the cretaceous

iran creatures from the outrageously

large to the outlandishly terrified

incredibly bizarre

but every dinosaur no matter how radical

is hatched from a name

and like the well-engineered bodies they

will eventually grow into evolution has

created some of the most advanced eggs

history has ever seen an egg is like a

space capsule everything that the embryo

is gonna need is pretty much

an evolution took care of something else

the shell of dinosaur egg is built like

a motorcycle helmet able to withstand a

severe shock and then for even more

protection there's the albumin or egg

white the egg white is kind of a gel and

has multiple functions one is to keep

the embryo that's developing moist but

also acts as a shock absorber because if

the egg gets too charred you don't want

to you don't want to kill the embryo

less developing virus sudden shock a

well constructed a makes it that much

more likely that a hatchling will

survive and when that youngster grows up

it will pass on those very same genetic

traits that saved it in the first weeks

of life inside this tiny home a single

fertilized cell divides rapidly

these cells become a myriad of tissue

types that will make up bones skin

nerves and organs

dividing cells also form brains senses

and weaponry needed to protect this

dinosaur as it grows up

at this embryonic stage tiny genetic

differences changes that might only

affect one-in-a-billion traits make the

difference between a hatchling that

survives and one that's chomped

stepped on or even starves to death

to be able to actually see a baby t-rex

hatching

would be something akin to the

excitement she would get by going into

space you know so I mean I probably

would give maybe just a little more

money to go into space anyway to see a

t-rex hatching but not much more

[Music]

the age of dinosaurs is an era of

sophisticated biodiversity diversity

that proves one thing

evolution creates not just one but many

strategies for survival

yet for one creature that strategy seems

almost true

over her lifetime a female sauroposeidon

produces thousands of eggs yet only two

or three survived to adulthood

so what that tells us is that many many

almost all of the Austral are being

killed and eaten by predators

losing virtually all of your offspring

to carnivores sounds like an

evolutionary nightmare but in fact it's

just the opposite that one survivor that

one in 3,000 may just possess the single

trait giving it the ability to make a

quick escape as its sibling Zuri

or it might inherit a genetic

combination that allows it to grow

stronger bigger and maybe even just a

tiny bit faster the sauropods were

probably digging these nests probably

kicking out a little hole with the hind

foot squatting down depositing a few

eggs maybe five or six maybe a dozen

covering them up and then just walking

away forgetting about them for months

sauroposeidon eggs are left unguarded

warmed and protected by nothing more

than dirt and rotting vegetation

the nest become killing fields so I'm

sure that many many sauropod nests were

found in destroyed by predators before

the babies can even hash

yet was so much stacked against them

sauroposeidon thrive for 15 million

years

they're an evolutionary success story

but some scientists believe they could

have achieved even more if I was going

to engineer a super sauropod I'd give it

a bigger brain because it would be a

negligible investment we're talking

about a few more pounds on an animal

that already weighs 40 or 50 tons but if

it was smarter then it could practice

more extensive parental care the babies

themselves could be smarter it could put

fewer resources into reproduction and

more resources into growing larger

growing larger when you already wait

victory tons sounds impossible but it

isn't

I wanted to drill a 210 square pot

that's right start about seven more

pounds of brain

animal ever grew to 200 tons but

evolution did keep dinosaurs going for

165

they adapt to a world of tremendous

geologic change and sorry global town

we're little States the same

but then comes catastrophe from the sky

a meteorite strikes the earth

after the great dinosaur die-off these

huge and magnificent creatures seemingly

cease to exist

but things are not always as they appear

maybe dinosaurs are still here maybe

they're still all around us it turns out

clues are everywhere

a sauroposeidon could raise its massive

head over 60 feet into the air

but this was only possible because their

neck bones were so light almost 85%

Hollow

the neck vertebrae have swore preside

endure four and a half feet long but

they were almost all air

a kir expert is seven tonnes in weight

as big as a killer whale he elects Ora

Poseidon it's bones were honeycombed

with empty spaces

and there's another clue

the lungs of deinonychus t-rex and syrup

aside are designed like those of a

living thing we see all around us every

day

we look at the respiratory system does

not like those mammals at all it's like

something much smaller much more

delicate like birds

graceful soaring on the breeze one of

the best adapted and most common

creatures to inhabit the earth

birds are almost certainly descended

from the mighty dinosaur

everybody knows the birds have hollow

bones a lot of people think that's an

adaptation for flight but not a lot of

people realize is that birds inherited

their hollow air-filled bones from their

dinosaur ancestors

all around the world birds like

dinosaurs bill just about every leash in

every environment from the rainforest to

the mountains to the Seacoast

an ostrich at nine feet tall and over

300 pounds is the largest modern burger

that may pale in comparison to a

Tyrannosaurus Rex of the giant sort of

beside

but the Biodesign which give birds their

ability to get up in the air to maneuver

in flight and to reproduce are clearly

found in dinosaurs

genetic traits that once allowed

dinosaurs to grow to mammoth proportions

or survive in a world of brutal killers

features honed by 165 million years of

evolution simply never went away

tools that once served dinosaurs so well

have adapted to serve new functions in

modern Birds

dinosaurs used hollow bones to grow very

large

birds use them to save weight dinosaurs

used air sacks to move air along their

massive necks birds use air sacks to

stay aloft for long periods it turns out

that in many ways the only difference

between dinosaurs and birds is scale

and there's even evidence that many

terrestrial dinosaurs nearly had what it

takes to fly in fact the arms and hands

of Deinonychus worked remarkably like a

bird's wings for Deinonychus this

high-speed motion creates a grasping

claw able to dig deep in the flesh

in a bird the same boat allows its wings

to flap at those same high speeds the

key to point

deinonychus arms were very specialized

much like modern birds in fact like a

modern bird they have the ability to

fold their arms or their limbs if you

don't to the side this is the same

folding ability that allows birds to fly

today the wings of a bird in flight are

a living example of Deinonychus his claw

in action

look at a bird out in nature that's

moving it swings back and forth the

pattern of the joints an angle of the

joints in the wings of birds closely

match the pattern we see and Deinonychus

and there's one final clue a clue that

all but definitively connects birds and

dinosaurs and it's something you least

expect something scientists call the

first time we call it a wishbone

wishbones today only exists in birds

he had virtually every one of the most

ferocious carnivorous dinosaurs

[Music]

the evidence points to one single

conclusion the mighty t-rex the wily

Deinonychus

the graceful ketse koalas

the giant sword sight

[Music]

were just super-sized Birds

so next time you sit down ready to carve

that Thanksgiving turkey

just imagine what that bird's

great-great great-great grandparents

you

dinosaurs are the planets ultimate

living creatures they survived for over

165 million years the key to that

success our bodies well designed on the

outside and precision-engineered

on the inside

they're advanced busy ology comes down

to one thing adaptation the result of

both natural and sexual selection over

more than 10 million generations these

giants continually improve

creating one better dinosaur after in

the

natural selection is eliminating those

animals that are not smart enough to do

the job they need to do eliminating the

clumsy and favoring from little stops

pointing backwards delete the weapons

pointing forward

and Tyrannosaurus Rex a snake claim to a

territory of his own

male soon-to-be adults fight for the

chance to prove they've got the right

stuff females choose carefully only the

strongest fittest or smartest males will

do

and when it comes to reproducing

something else is critical time

most big predators today breed

home-grown short interval and year

actually most animals today

preed only in a short intro a couple

days their weekly to the outstanding

exception being that peculiar predatory

species Homo sapiens

dinosaurs the most sophisticated best

engineered highly adapted survival suits

ever created by Nature

these guys were very successful 165

million years of evolution gives these

prehistoric Giants weapon defenses an

advanced senses able to put modern

animals to shame now with cutting-edge

imaging technology we can go deep into a

dinosaur's body and reveal how

adaptation makes them strong smarter

tougher it's the ultimate mystery what

allowed them to be so successful for so

long

[Music]

those that have the the brainpower to

accomplish these complicated tasks

evolution means some species thrive

while others are driven to extinction

and in animals with such dangerous

armaments competition for survival can

be better

late spring

the Cretaceous period

[Music]

adolescence is a critical time

dinosaurs are preparing to mate

some will succeed others will fail

and Darwinian calculus you can be the

finest hunter in the land and if you

can't attract and hold on to desirable

made with desirable genes you're a loser

a loser whose genes are about to reach

the end of the life

mating is serious business with

significant repercussions of male and

females female looking at a male what

they're doing without actually thinking

it consciously is evaluating the

potential genes over there are your

genes good ones well your genes mix with

my genes make a really healthy very

competitive youngsters

clues the males are approaching sexual

maturity about the crest on an

adolescent parecer Ovilus is now fully

developed

Triceratops horns grow