- What if I told you that
Jurassic Park isn't a total fantasy?
That a future where we interact with animals
only seen in museums might be possible?
dodo birds, woolly mammoths, Tasmanian tigers.
That's the world scientists and researchers
are working on as we speak,
and not T.rexes or Brontosauruses.
I'll get to why scientifically we won't be doing that.
Instead, scientists are focusing on species
that could reverse some of the damage
that humans have done to the biosphere.
And there might be enough DNA
found and preserved extinct animals
in museums all over the world
to jumpstart this resurrection.
One bird in particular, could help regenerate
the forest of North America, the passenger pigeon.
I'm Sinead Bovell, a futurist, a tech entrepreneur,
and your host of "Far Out".
Today, let's explore the world of de-extinction.
[playful music]
The biosphere is the region of Earth that supports life.
It includes all land, water,
and a thin layer of air above the earth.
For 3.5 billion years, the Earth's biosphere
has hosted countless species, each playing a different role
in balancing the world around it,
and some more than others.
Like the five-ton woolly mammoth.
Its grazing patterns in how it stomped around the land
had an outsized effect on the Eurasian tundras.
It helped to grow and protect permafrost in the region.
Keeping tons of CO2 locked in the ground.
And for thousands of years,
humans have played an outsized role in the biosphere,
mostly a negative one.
Since 1970, almost 70% of the wildlife population
has died off due to human interference.
But what if we could undo some of that damage
by restoring ecosystems to the way they existed
before humans tip the scale.
What if the woolly mammoth could help
rebalance the biosphere again
through a process called de-extinction?
This could be possible, and there are scientists
all around the world working to bring this goal to life.
Scientists like Dr. George Church,
the godfather of genomics,
who is leading a team of researchers
working on bringing back the woolly mammoth
and the Tasmanian tiger.
So, what does the future look like to Dr. Church?
- Well, best way to predict the future
is to try to change it.
My lab projects tend to have three components,
some kind of basic science, some new technology
and some focus on long-term societal needs.
Our main goal is focused on the environment
and the endangered species.
As a scientist, I might be considered pessimistic
in that I stick to the facts.
But as a technologist, I'm optimistic
that there's no real barrier
to testing hypotheses and changing the future.
- The species that Dr. Church wants to bring back
are called keystone species,
because of their outsized role in affecting ecosystems.
Another keystone species scientists are homing in on,
the passenger pigeon.
Passenger pigeons were the most populous bird
in North America, and possibly the world.
Some estimates put the total number
of passenger pigeons in the billions.
Flocks were known to be a mile wide and 200 miles long.
And when they flew overhead,
the flock would blot out the sun for hours at a time.
But then the 19th century happened.
Industrialization, over hunting,
human expansion, human interference
and in a few decades, their population plummeted.
By 1914, the last surviving passenger pigeon
died in captivity.
Researchers think the passenger pigeon
was instrumental in creating more biodiversity
in North American forests,
because their massive flocks acted almost
like natural forest fires,
destructive, but in a good way.
They would swarm in like a tornado,
stripping trees bear and decimating canopies.
But that allowed sunlight to hit the forest floor
and created more diverse plant species to flourish.
That canopy disturbance is thought to be the start
of a chain reaction that helped forest regenerate
and spawn new life from insects to reptiles,
to deer, to hawks.
All in all, the passenger pigeon was essential
to the health of the vast hardwood forest
that dominated pre-colonial America.
It was all part of a massive balanced cycle.
So, the question becomes,
if the passenger pigeon were brought back
would that cycle begin again?
That's what scientists are trying to find out.
But first, they need to figure out
the actual science of de-extinction.
To de-extinct a species, you would need
a copy of its genetic code, aka its DNA.
Normally, DNA has a half-life of around 500 years,
meaning after 500 years half of the DNA
of the deceased species will have decayed.
But if that DNA was frozen,
it can be preserved for a very long time.
For example, a 1.2 million-year-old woolly mammoth tooth
was found frozen in the Siberian permafrost.
And from that tooth, researchers were able
to sequence the DNA of mammoths.
And if your mind is going to Jurassic Park
mosquitoes trapped in amber scene,
amber isn't great for preserving DNA,
it doesn't actually freeze, it's porous,
so bacteria seeps in and it just breaks things down.
Long story short, no Velociraptors for now,
which I'm okay with.
Passenger pigeons went extinct in the 20th century.
So, scientists have a fairly complete DNA sample for them.
The next step is to identify the closest living
genetic relative of the extinct species.
In this case, it's the band-tailed pigeon.
Why do we need to do that?
Because the truth is we aren't
fully bringing back a species.
It's a lot more complicated than that.
- What people imagine when they think of de-extinction,
the first thing that comes to mind is
we are going to have an exact copy of a woolly mammoth,
an exact copy of a passenger pigeon,
but that is just not possible.
- This is Dr. Beth Shapiro,
a leading voice in the de-extinction quest
and the author of "How to Clone a Mammoth".
- What we're really talking about
is resurrecting and bringing back extinct traits,
extinct behaviors, extinct capacity,
to fill some sort of ecological niche
that might be vacant because of an extinction.
We can't bring back a passenger pigeon,
but we might be able to take a species that's alive today,
like the band-tailed pigeon
and modify it in such a way that it can fill
at least part of the niche
that was once filled by the passenger pigeon.
- So, we can't magically bring back a 200-year-old bird,
and honestly, I don't think we would want to.
- Every organism is more than the sequence
of the A's and C's and G's and T's
that make up its DNA code.
It's genome sequence.
We are a combination of our DNA
and the environment in which we live.
And for most extinct species,
those environments don't exist anymore.
- But the band-tailed pigeon does exist.
In fact, it's thriving.
Its DNA isn't too far off from the passenger pigeon.
So, scientists are working on
identifying the key genetic sequences
in the band-tailed pigeon that they wanna change.
Can they give it traits from the passenger pigeon
and create a hybrid bird?
One that carries on the genetic
and ecological importance of the passenger pigeon,
but can survive in a modern biosphere,
like the band-tailed pigeon?
Can they make a passa-band-tailenger pigeon.
To create hybrid mammals and de-extinct traits
from species like the woolly mammoth or the Tasmanian tiger
scientists use a method
called somatic cell nuclear transfer.
You might know it as cloning.
This technology isn't new.
In the nineties, scientists cloned a sheep named Dolly
using pretty much the same methods.
But birds have a very different
reproductive physiology than mammals.
For the passenger pigeon, genetic engineers
have to move upstream and edit the stem cells
that will eventually become sperm or egg cells.
These cells are called primordial germ cells or PGCs.
Scientists remove these PGCs from a band-tailed pigeon,
edit parts of the genome to reflect passenger pigeon traits,
inject those edited cells back into the bird
and eventually, when the band-tailed pigeon
goes to reproduce its offspring
will possess the hybrid traits.
[pigeon cooing]
We know that this will work.
- There was some work several years ago
where scientists injected duck primordial germ cells
into a chicken embryo.
That chicken as an adult,
was a perfectly normal female chicken
except some of her eggs were duck eggs.
When she was fertilized with duck sperm and laid some eggs
they all hatched into perfectly normal ducks.
- But even if we can pull this off
and resurrect the passenger pigeon, should we?
This isn't some species killed off via natural selection
or natural climate change like an ice age.
We killed them off and now we wanna bring them back
to help save us and reverse our environmental mistakes.
And what if this hybrid pigeon damages delicate ecosystems
and pushes other animals onto the path of extinction?
There are too many examples
where humans have introduced invasive species
and altered environments beyond repair.
Are we just doing this again?
And who gets to decide where the passenger pigeon roosts?
How regulated does this process have to be?
And when you think about it,
by bringing back an extinct species,
we are immediately creating a new endangered species
that needs protection and resources.
Resources that could be put
towards other conservation efforts.
At the same time, our planet is in a dire state
and it's gonna take some big solutions
to get us on the right track.
Solutions as big as de-extinction.
And if we get it right, the science and the ethics,
we could help balance the biosphere
closer to what it was before human interference.
And that won't just benefit us,
but all of the other species on this planet
who deserve to have their ecosystems back.
I think we should continue
to explore the science of de-extinction,
while also opening up these conversations to the public
so we can steward this process as responsibly as possible.
And if we get this right,
I think the future will be a really great place.
What do you think of de-extinction?
What animals would you de-extinct?
Let us know in the comments below.
[gentle music]