All language subtitles for Walking with Dinosaurs 2025 s01e01 ENG01

-[Narrator]
Survival of the fittest

often sounds like a fight
to the death.

But for two species of dinosaur,
the opposite was true.

This is the story
of how they allied together

to fend off predators
in their march

towards the Arctic Circle.

Pachyrhinosaurus
and Edmontosaurus

were two big herbivores
who have been found

as far north
as modern-day Alaska.

They lived in gigantic groups
of up to 40,000 strong.

And each year, both herds
undertook epic migrations,

heading right towards
the Arctic Circle.

But new discoveries suggest
that these two species

were much more than coincidental
travel companions.

-[Henry] Here it is,

an impossibly good
dinosaur fossil.

-[Narrator] One spectacular find
could hold the key

to unlocking the secrets
[deep bellows]

of how two totally different
species worked together

to survive such
a dangerous journey.

-[Henry] This is the closest
thing you can get

to seeing a living dinosaur
in the wild.

-[Narrator] But why would
they make such a journey

in the first place?

The simple answer
is food and sunlight.

Seventy-three million years ago,

these dinosaurs lived in
a very different North America,

one split in half
by a huge impassable sea

known as the
Western Interior Seaway.

Pachyrhinosaurus
and Edmontosaurus

lived right here.

Hemmed in by mountains
on one side

and the sea on the other,

they were unable to get
to warmer climes farther south,

which made their winters
brutally harsh,

so harsh that you can
even see it

in their bones.

Every winter, their growth
would slow down so much

that you can literally see it
under a microscope,

similar to counting tree rings.

But in the spring,
their fortunes changed

as they headed further north
towards the Arctic.

Bleak and dark in winter,
in the summer,

the prehistoric Arctic
became a paradise,

where sunlight 24 hours a day

helped produce bountiful
supplies of vegetation.

But reaching the promised land
was far from easy.

This migration was fraught
with danger.

Packs of tyrannosaurs
lurked nearby,

waiting for an opportunity
to pick off

a member of the herd.

So maybe Pachyrhinosaurus
and Edmontosaurus

traveled together
for safety in numbers.

But palaeontologists
like Henry Sharpe

think they were more
than just travel companions

and allied with each other
to fend off predators

using their
complementary strengths.

-[Henry] If you were an
Albertosaurus trying to sneak in

and get an easy meal,
it would be much harder

if they had the vision
of Edmontosaurus

and the armaments
of Pachyrhinosaurus

all together in the same area.

-[Narrator] This theory
of cross-species cooperation

isn't so wild when you consider
the natural world today.

In the Serengeti,
zebras and wildebeest

form a similar alliance,

using zebras' better vision
to spot danger,

with wildebeest providing
the muscle.

-[Henry] It's called mutualism.

It's animals benefiting off
the presence of another.

It's ridiculous to suggest
that dinosaurs didn't do that

in some regard when we
understand how frequent it is

in modern animals.

So, I definitely expect herds
of Pachyrhinosaurus

and herds of Edmontosaurus

to be using the presence
of the other

to increase their own safety.

-[Narrator] But just how far
did this dinosaur alliance go?

Thanks to a unique
Edmontosaurus skull,

Henry thinks this wasn't just
about moving together

or even relying on each
other's physical strengths.

They may have actually
been talking to each other.

-[Henry]
This is a dinosaur mummy.

This is, uh, the closest thing
you can get

to seeing a living dinosaur
in the wild.

-[Narrator]
This rare, mummified skull

has been preserved with some
of its soft tissue intact,

offering a window
into this dinosaur's biology.

-[gasps]

It's so cool.

I mean, the chances
of an animal being fossilized

are one in a million.

And the chances of that fossil
having skin like this

is one in a billion.

Just an impossibly
good dinosaur fossil.

-[Narrator] The skull
has its cranial crest intact,

which Henry thinks

could have been used
to send visual warning signals

to other herd members.

-[Henry] We're looking at
what this animal

is using to communicate.

We're speaking dinosaur
right now.

We're, we’re saying
hi, you know.

We're paying attention
to the crest

that it wants everyone
to pay attention to.

It's a billboard.

It's trying to say,
hey, look at me,

pay attention to me.

The signaling
that these dinosaurs were doing

could definitely
be translated

between an Edmontosaurus
and a Pachyrhinosaurus.

We just didn't think
that Edmontosaurus

had anything like that
until this specimen was found.

-[Narrator] There's still
a long way to go

before we can understand

how much different
dinosaur species

were able to communicate
with each other.

-This guy's kind of the,
the Rosetta Stone

for understanding that aspect
of dinosaur biology.

-[Narrator] It's possible
that survival of the fittest

on prehistoric Earth
might have been less

about hunting one another
and more about working together.

[deep bellows]