Hello. This is 6 Minute English
from BBC Learning English.
I'm Neil.
And I'm Sam. In this programme,
we'll be hearing a news story
linked to the 'Nature versus
Nurture' debate, not concerning
a human, but a rhinoceros!
The extremely rare northern
white rhino of East Africa
was on the brink of extinction
when the second-to-last living
male, Suni, died in 2014,
leaving behind two females,
Najin and Fatu - the last living
creatures of their species.
Conservationists started an
artificial breeding programme,
using eggs from the females and
sperm from Suni to produce
an embryo - an unborn animal
in the very early stages
of development.
Recently there's been a
new development in the
story, but before we hear
more, it's time for my quiz
question. The name,
rhinoceros , comes from
the ancient Greek, but
what exactly does
it mean? Is it:
a) thick skin, b) horned
nose, or c) small eye?
That's a tricky one, because
rhinos have all three!
OK, I'll guess a) thick skin.
OK, Sam, we ll find out later.
Now let's get back to the
story of those precious
northern rhino embryos.
Well, the good news is
that so far five embryos
have been produced.
They're being frozen until
they can be implanted in
southern rhinos - the
northern species'
more common cousin.
Conservationist Thomas
Hildebrandt runs the rhino
breeding programme.
He spoke to BBC World
Service's, Science in Action,
who asked him whether
the embryos were
genetically from the
northern species.
Absolutely right. They're not
hybrids, they're pure
northern white rhino
embryos which were
generated with the
desired breeding partner,
Suni, who died in 2014. So
we have embryos which
have a very high quality...
there's no inbreeding effect
on these embryos, and it's
so important to make the
next step, to transfer these
embryos because we can
preserve life - biological material -
in liquid nitrogen, but what we
can't do - we can't preserve
social knowledge and
therefore we need desperately
a calf on the ground so that
these two existing northern
white rhinos, can teach the
new calf how to behave as
a northern white rhino.
Having genetically pure embryos
prevents the birth of hybrids -
animals that have been bred
from two different species.
It's also important the embryos
have no inbreeding - breeding
of a young animal from two
closely related parents,
because this can
cause disease.
Fortunately, Thomas and
his team have preserved five
healthy and genetically pure
northern rhino embryos
in liquid nitrogen.
But while they can preserve
nature, what Thomas's team
can't provide is nurture - the
social knowledge that a young
northern rhino - or calf - can
only learn from
other northern rhinos.
And since Najin and Fatu,
the last remaining northern
rhinos on Earth, are
getting old, the race is
on to breed a young rhino
calf before they die.
The good news for the
survival of the northern
white rhino is that
experiments to implant
the delicate embryos in
southern rhinos
have been successful.
Here's Thomas Hildebrandt
again talking about these
recent experiments with BBC
World Service programme,
Science in Action:
We will, for sure, not wait
until this pregnancy is
completed because it takes
16 months for a full
pregnancy in a rhinoceros.
So if this embryo implants -
and we can see that on
ultrasound... and - forms a
nice placenta, that is
the goal for us to proceed
with the next step on the
northern white
rhino embryos.
Normally it takes 16 months for
a female rhino to complete
her pregnancy - the state in
which a woman or female
animal has a baby
developing inside her.
But in the case of the
northern rhino, the race
is on to birth calves who
can learn the rhino rules of
social behaviour from
Aunty Najin and Granny
Fatu while they're still
alive...
which is why conservationists
are monitoring the pregnancy
using ultrasound - a
procedure using sound
waves to create images of
internal body parts, or in
this case, growing
rhino babies.
It's an unusual episode in
the ongoing 'Nature versus
Nurture' debate.
And hopefully a big step
towards restoring the
northern white rhino
population so that future
generations get to see these
magnificent creatures with
their thick skin,
horned nose and...
... and small eyes, Neil? So
what was the answer
to your quiz question.
Yes, I asked you what the
name 'rhinoceros' meant.
What did you say, Sam?
I guessed it was a) thick
skin. Was I right?
Well, rhinos certainly do have
thick skin, but their name
actually comes from the
Greek meaning, 'horned nose'.
Well, luckily I've got a
thick skin too, so I won't
take it personally! Let's
have another look at the
vocabulary we've learned,
starting with embryo - an
unborn animal or human
still inside its mother's womb.
A hybrid is an animal or
plant that has been bred
from two different species.
Inbreeding is when a young
animal is born from closely
related parents.
A calf is the name for the
young of several large
mammals including cows,
elephants and whales,
as well as rhinos.
Pregnancy means being
pregnant or growing a
baby inside you.
And finally, ultrasound is
used to see internal organs or
a baby developing
inside a woman.
And that's all from this
species-saving edition
of 6 Minute English.
Goodbye!
Bye bye!