[MUSIC PLAYING]
LEE ALLEN DUGATKIN:
Thanks, Bjorn.
And I've really been looking
forward to coming today.
I actually grew up just
a stone's throw away
in Stuyvesant Town, and my
dad owned a toy store right
across the street from there.
So it's always fun
to come home but also
because a lot of my work
recently, in the last decade
or so, has been on the
history of science.
And I actually use
Google tools all the time
when I'm doing that
work, and they're
extraordinarily helpful.
So it's a pleasure to have a
chance to talk with you today.
So I'm going to start
with a question, right?
Suppose that you could
build the perfect dog.
What would be the key
ingredients in your recipe?
Well, you definitely want
cute, right-- maybe something
with floppy ears
and a curly tail
that wags in anticipation
whenever you're around.
You'd want smart.
You'd want loyal,
and you'd definitely
want unconditional love.
The thing is that
you do not need
to build this animal because,
for the last 60 years,
a dedicated team of Russian
geneticists in Siberia
have been building it for you--
the perfect dog--
except, as you might
guess from the title of today's
talk, it's not a dog at all.
It's a fox-- a domesticated fox.
They built this in the
minus-40-degree winters
of Siberia, but
more importantly,
they built it in the blink of
an eye in terms of evolutionary
time--
a hundredth of the time
that it took our ancestors
to domesticate wolves into dogs.
This is my friend and colleague
and co-author Lyudmila Trut.
Lyudmila recently
turned 85 years old,
and every day including
today for the last 60 years
she has led what's come to
be known as the silver fox
domestication experiment.
And for the last 10
years or so, I've
had the honor of working with
her as a historian of science
to tell the story of what they
have done to as many people
as we possibly can.
So today, I am going to tell you
about domesticated foxes that
will melt your hearts
and lick your ears just
like this guy did five seconds
after they put him into my arms
in Siberia.
More than that,
though, I'm going
to tell you about
cutting edge work
on this process of
domestication, which is not
something only of
interest to biologists
because, if you think about
it, when our ancestors began
domesticating
plants and animals,
we dramatically changed our
own evolutionary history.
We would be very, very different
if we had not done that.
And this experiment that
we're going to talk about
is the gold standard
for understanding
how domestication comes about.
So I'm going to try and
give you an overview
of what they've been doing
and why it's important.
60 years-- the experiment
starts with this fellow,
Dmitri Belyaev.
In the late 1930s, Belyaev
was an undergraduate student
at a place called the
Ivanova Agricultural Academy
outside of Moscow.
And while he was there,
he studied genetics,
and because it was an
agricultural academy,
he had all sorts of interactions
with domesticated species.
When he graduated Ivanova, like
every Soviet male of that era,
he went and fought in World
War II for four years.
After that, he came back
and landed a position
as a research scientist at
a place called the Central
Research Laboratory for
Fur Breeding Animals,
also in Moscow.
And it was there
that Belyaev came up
with the idea that
would eventually
become the silver fox
domestication experiment.
And it started like this--
he knew from his interaction
with domesticated species
and also from reading
Darwin's famous book
about domestication-- he knew
that many domesticated animals
share a whole suite
of characteristics.
So they tend to have things like
floppy ears and curly tails.
They also tend to have
sort of juvenilized body
and facial features compared
to their wild ancestors.
They tend to have low
stress hormone levels.
They tend to have all sorts of
variation in their coat color,
and they also typically
have much longer
reproductive seasons than
their wild ancestors.
Not every domesticated
animal has
every one of those
characteristics,
but most have many of those
characteristics, so much so
that that whole thing--
the floppy ears, the curly
tails, the low stress hormone--
all that is referred to today
as the domestication syndrome.
And Belyaev thought about this,
and he thought, you know, this
is really weird because our
ancestors domesticated species
for all sorts of
different reasons.
Some, like horses,
we domesticated
for transportation.
Others we domesticated
as food sources.
And yet others, like
dogs, we domesticated
for some combination of
protection and companionship.
Yet, regardless of what
we domesticate them for,
they tend to have many
of the characteristics
in the domestication syndrome.
Why?
And Belyaev's hypothesis
went like this--
the one thing that
our ancestors always
needed in whatever species
they were trying to domesticate
was an animal that would not
try and bite their heads off.
And so he hypothesized
that the earliest stages
of all animal
domestication events
involved our ancestors
choosing the calmest, tamest,
friendliest towards
human animals.
He further hypothesized
that, somehow--
and he really didn't know how--
but somehow, all of those
other characteristics
in the domestication syndrome--
longer reproductive periods,
juvenilized facial
features-- all
that was somehow genetically
connected to choosing animals
based on how friendly
they were towards humans.
And he decided he would test
these ideas in real time,
using the foxes
that he became very
familiar with at the Laboratory
for Fur Breeding Animals
because, at that laboratory,
the two key species they worked
with were foxes and mink
because there was so much money
associated with fox
fur and mink fur.
So he decided he would
test these ideas in foxes.
And the experiment he envisioned
was very basic at its core.
He imagined testing
hundreds of foxes
and choosing the calmest ones--
the ones that are most
friendly towards humans--
preferentially breeding them.
Then when their pups
grow up, test them.
Preferentially
choose the ones that
are friendliest towards humans.
Do this generation after
generation after generation.
Foxes breed once a year,
so essentially one year
equals generation.
He would do this
every generation.
And he would see--
first of all, was he, in fact,
getting inherently calmer,
friendlier to human animals,
and strictly choosing them
based on how friendly
they were, did he also
begin to see the
emergence of other traits
in the domestication syndrome?
Did they start showing
lower stress hormone
levels or other characteristics
of domestication syndrome?
This is a classic experiment
in evolution and genetics,
but Belyaev had a problem,
and it was a big problem
because, as he came up with
this idea in the mid-1940s,
it was a time when it was
illegal to do modern genetics
in the Soviet Union.
And the reason
that it was illegal
was because of this
person right here--
Trofim Lysenko.
Lysenko was a
fraud, a charlatan,
a pseudo-scientist
who had risen up
both in the scientific and
political ranks of the Soviet
Union.
And what Lysenko said was
that modern genetics was
bourgeois science being
promulgated by wreckers
and spies from the West,
that instead, he argued,
a long disproven idea known
as Lamarckian inheritance
was, in fact, not only
correct but more in line
with Soviet philosophy.
He then went and made
up a bunch of studies
that he never did to suggest
that he was, in fact, right.
And by doing this, he rows
up to become, not only one
of the most powerful
scientists in the Soviet Union,
but Stalin's right-hand
man on science.
So this picture comes
from a conference
where Lysenko was giving one
of these fire-spitting talks,
calling Western geneticists
saboteurs and wreckers.
And when he finished, Stalin
stood up and yelled out,
bravo, comrade Lysenko.
Because of Lysenko, thousands
of Soviet geneticists
lost their jobs, hundreds
were thrown into prison,
and about 20 were actually
murdered by Lysenko's thugs
for doing the crime of
modern Western genetics.
This is the environment in
which Belyaev is conceiving
an experiment in genetics.
Nobody knows better
how dangerous
this is because one
of those 20 people who
was murdered by Lysenko was
Belyaev's older brother--
20 years older--
who had been an up
and coming star in
the field of genetics.
But Belyaev decided
this was too important,
and he was going to do it.
So he initiates a tiny,
little pilot study.
He has a friend who runs
a fox farm in Estonia,
and there are hundreds
of these fox farms
around the Soviet Union
and their satellites
because, again,
there's so much money
selling fox furs to the West.
So he talks to one
of his colleagues
in Estonia, who runs one
of these smaller farms,
and he says, here's
what I wanted to do.
I want to do an
experiment, where I select
the calmest, tamest ones.
And it's a small
pilot experiment.
It involves testing a couple
of dozen foxes every year--
test them on how friendly or
not they are towards humans,
breed the ones that
are friendliest.
And he and his colleagues do
this for four or five years,
and the results are promising.
Even in that short
amount of time,
they began to see animals
that were inherently
a little friendlier
towards humans.
Then Belyaev gets his
big chance to start
a full-blown experiment in 1958.
What happens is he is offered
a position as vice director
at a new institute
of biology in Siberia
in a place called Novosibirsk.
And this institute is
part of a place that
still exists today called
Akademgorodok, or the Academic
Village.
Basically, what happened was,
in the mid- to late-1950s,
the Soviet political leaders
and scientists worked together,
and what they did
was they cleared out
a large chunk of Siberian
forests near Novosibirsk,
and they built two dozen
world class institutes
in associated science.
So there was the institute
that Belyaev was involved
in as vice director in biology.
There were institutes in
chemistry, physics, early
computer science,
and so on, and so on.
They literally brought
in tens of thousands
of scientists and
associated people
to build this Academic Village.
So Belyaev knows now
that, as vice director
of this new institute
of biology there,
that he is going to have
the power and the money
to start a full-blown silver
fox domestication experiment.
But because of all the
administrative stuff
he's going to have to do as
vice director, what he's not
going to have is the
time to be the person
to lead the experiment
on a day-to-day basis.
So right before he moves to
Akademgorodok, while he's still
in Moscow, he goes on a hunt
for the perfect young scientist
to lead this experiment,
and he does this
by going to Moscow State
University, which is not
only one of the best but one of
the most beautiful universities
in the world.
And he talks to some
colleagues he has there,
and he lays out the
ideas and says he's
looking for a young scientist.
So one of the people who comes
into interview for the job
is 25-year-old Lyudmila.
The interview happened in 1958.
When you talk to her today, it
seems as if it happened just
yesterday.
The first thing that struck her
was that Belyaev immediately
treated her like an equal.
So in 1958, Soviet science
was very patriarchal.
But here was a vice
director of an institute
talking to a newly
minted undergraduate
and treating them like an equal.
And that mattered.
So Belyaev lays out the idea.
We're going to test hundreds
of foxes every year.
We're going to
choose the calmest,
most friendly towards
human foxes, breed them.
We're going to do this
generation after generation,
see-- do we get more
calmer and calmer animals,
and do we begin to see
floppy ears and curly tails
and all the stuff in the
domestication syndrome.
And Lyudmila loves the idea.
She thinks it's a
brilliant experiment,
and she also likes
the idea of moving
to this new scientific oasis
in the middle of Siberia.
But before she gets too excited,
Belyaev stops her and says,
look, you need to know
a couple of things.
First of all, even though
Lysenko is not as powerful
as he used to be, if he decided
to make an example of us,
he could still throw
us into prison.
Lyudmila knew that anyone who
studied biology knew that,
but it meant something that
Belyaev stopped her and said,
think about this.
And the other thing he said
was, I've run this little pilot
experiment.
It's promising.
But this is an
experiment in evolution.
It could take 10 years before
we find anything interesting.
It could take 20 years.
She remembers Belyaev
saying to her,
it could take your whole life.
But she was hooked.
He liked what he saw.
He offered her the position.
Six months later,
Lyudmila, her husband,
and their two-year-old daughter
hop on a train from Moscow
to Siberia, which is
no easy train ride,
to begin the
full-blown experiment.
From day one, Lyudmila
would tell you
that her motto comes directly
from the wonderful children's
book, "The Little Prince," where
the fox tells the little prince
that you become
responsible forever
for what you have tamed.
So Lyudmila gets there, and
Belyaev has money and power.
But he still hasn't been able
to procure a very large area
to build a fox farm
right in Akademgorodok,
where they could
do the experiment.
He's working on that.
He's planning to do it.
But at the start, there
is no such place yet.
So for the first
year or so, Lyudmila
travels around the Soviet
Union to all of the-- you
know, to many of these fox
farms I've told you about.
All of them are owned by
the government, of course.
And she's trying to
find the perfect place
to start the experiment
until they have some place
at Akademgorodok to move it to.
And eventually, she
settles on one place
known as the Lesnoi Fox Farm.
It's an overnight, about 12-hour
train ride from Akademgorodok,
and Lyudmila's plan is that
she'll go down there four times
a year.
Some visits will be
for a couple of weeks.
Other visits will be
for a couple of months
to start the
full-blown experiment.
So this place
Lesnoi is gigantic.
It's a cash cow for
the Soviet government.
At any given time, there could
be 10,000 foxes at Lesnoi,
all being bred for pretty fur.
And when Lyudmila first
talked to the director
there and said what
she wanted to do,
he looked at her
like she was nuts.
Why would anyone want to
waste their time trying
to build a friendlier fox when
there's so much money to be
made for the government in fur?
But Lyudmila said
that Belyaev sent me,
and Belyaev's name now carried
enough weight that the director
said, fine, test 500 foxes.
It's not going to bother me.
Go ahead and do it.
So she begins the experiment,
and it works like this--
every day at 6 o'clock
in the morning,
she begins, and she works
methodically from cage to cage.
Each fox is in its own cage.
And she's going to score
them on how friendly
or not they are towards her.
And she is going to
score every fox twice--
once when it's a pup, and then
once again when it's an adult.
And she's going to
score them first
as she approaches the cage--
she'll note whether they are
friendly or not towards her--
then as she stands by
their closed cage, then
as she opens up the
cage door, and then
as she puts something--
typically a stick or her hand
in a very, very thick glove--
into the cage.
And she is going to score
them on a scale of 1 to 4,
where 4 means relatively
calm and friendly,
and 1 means relatively
not so, either aggressive
or running away and hiding.
So she scores every one of
around 400 or 500 foxes twice--
once when they're a pup,
once when they're an adult.
And then she takes the 105--
the 10% of the males and
then the 10% of the females--
who had the highest
aggregate score--
the friendliest of the foxes,
the top 10% friendliest foxes.
And she does this every year,
generation after generation.
Initially, Lyudmila
describes these animals
as fire-breathing dragons.
They're not
technically wild foxes,
but they're pretty close to it.
And most of them
acted the way that you
might expect foxes
to act, especially
if they are in a cage.
But even after just two
or three generations
of selecting the calmest,
tamest, friendliest animals,
there were a few--
and just a few-- foxes
like Laska and Kisa.
So you're looking
at Lyudmila holding
Laska, which means "gentle."
These animals were calm enough
that Lyudmila could hold them
in her arms.
And so she held hope that,
if the experiment goes
on long enough,
they really will be
able to find out some
fundamental things
about this process
of domestication.
So she goes back year after year
after year four times a year
and does the same thing.
In 1965, she comes up with
this classification system.
She has what she
calls Class III foxes,
and these are animals that are
either aggressive towards her
or run away, and they
never make the top 10%.
Then there are foxes
like Laska and Kisa
that are what she
calls Class II foxes.
These animals can
be held, but they
don't show any emotional
response towards Lyudmila.
And then there
are Class I foxes,
and these cannot only be held,
but they display friendly
behavior.
They wag their tails
as Lyudmila approaches,
and they whine and
whimper when she leaves--
no training, no teaching.
This is what they do.
In 1965, Class I foxes made
up maybe 2% of the foxes.
Today, they make up
80% of the foxes.
So all of that 10% that are
being selected-- they're
all coming from
Class I and Class II.
A year later, Lyudmila has
to expand this classification
system to what she
calls the Class
I-E, or the elite
domesticated foxes.
So here is a description
of those foxes
in Lyudmila's own words--
"In the sixth generation,
there appeared
pups that eagerly sought
out contact with humans,
not only tail wagging,
but whining, whimpering,
and licking our hands
in a dog-like manner."
In addition, some of those
elite domesticated foxes
were not only
wagging their tails--
they were wagging
their curly tails.
Wild foxes don't
have curly tails,
but curly tails are a classic
part of the domestication
syndrome.
It's the first of the
domestication syndrome traits
to appear in the
foxes, always keeping
in mind that the only
thing they use to determine
who is going to
breed is how friendly
are they are towards humans.
Whether you have a
curly tail or not
does not affect whether
you're selected to breed--
only behavior-- and
yet, still, here
is the first of the
domestication syndrome traits
to appear.
So a couple of years go by.
1967-- now Lysenko is gone.
He's no longer a threat.
Plus this is an important
year because this
is the year that the fox
farm in Akademgorodok
is up and operating.
This is what it looks like
on a nice day in the Siberian
winter.
Each one of these sheds
holds maybe 50 foxes,
and at any given time, there
could be 700 to 1,000 foxes
on the fox farm.
And this was a watershed
moment because it
changed the dynamics of the
experiment in a couple of ways.
First of all, it meant
that Lyudmila and a team
now could work with the foxes
everyday, not just four times
a year, even if it
is a couple of weeks
or a couple of months--
every day.
The other thing that was
really important to Lyudmila
was that, when she was
working down at Lesnoi,
Belyaev was too busy to
come visit very often, maybe
once or twice a year.
But now he's just 20 minutes
away at the institute,
and he can come and
interact with the foxes
anytime he wants.
And just as important, if
something major happens,
she can immediately get Belyaev
over to see what's going on.
And one of those
"something importants,"
one of those major things was
this little guy right here--
Mechta, or Dream.
Dream was the first of
the domesticated foxes
to have droopy, floppy ears.
So here's the deal about
foxes and their ears.
In the wild, foxes
do have floppy ears
till they're about
six weeks old.
And then their ears shoot
ramrod straight the way
that you might imagine
a fox in the wild.
Well, at six weeks, Dream's
ears were still floppy.
Two months, they
were still floppy.
Three months, they
were still floppy.
Four months, they
were still floppy.
Lyudmila calls
Belyaev out there,
and Belyaev looks at
Dream, turns around,
and asks Lyudmila, what
kind of wonder is this?
Now they were seeing yet another
trait in the domestication
syndrome, not only curly
tails, but floppy ears-- all
as the result of selection on
behavior and behavior alone.
Belyaev used to take a
slide of Mechta to talks,
and when he would come back
from these talks-- by this time,
they were not only
in the Soviet Union,
but all around the world.
When he would come back,
he would tell Lyudmila
that his colleagues would
come up to him after the talk
and accuse him of trying to
stick a picture of a dog puppy
up on the screen to
convince them that the fox
experiment was working.
That's how much Mechta
looks like a dog.
OK, so the experiment goes on
year after year after year.
And one of the things
that Lyudmila and her team
have always been
doing along the way
is taking blood samples so
that they can look for changes
at the hormonal level.
So by 1974-- so
about 15 generations
into the experiment-- what
they're finding is that
their domesticated foxes
have about a 50% lower level
of stress hormones--
corticosteroids--
than wild foxes.
What's more, by this point,
they have started a control line
in the experiment.
So in the control
line, they test
the foxes exactly the
same, but who gets to mate
has nothing to do
with how friendly they
are towards humans or aggressive
they are towards humans,
so it's a nice control.
When they compare the
domesticated foxes
to the control, they also find
that the domesticated foxes
had about 50% lower
stress hormone levels.
And they were also beginning to
see all sorts of other things
appear in their
foxes by this time.
Domesticated pups
by the mid '70s
opened their eyes, on average,
a day earlier than the control
foxes or wild foxes.
Domesticated pups respond
to sounds two days earlier
than typical foxes.
Females have a slightly
extended reproductive season.
Typically, wild foxes breed for
about 10 days in late January
or early February.
Domesticated foxes, particularly
the elite domesticated foxes,
were in breeding state
for about 14 days--
so a real difference,
not dramatic,
but a real difference.
Yet another one of the traits
in the domestication syndrome--
it's typical for
domesticated species
to have longer
reproductive periods
than their wild ancestors.
And even, you also see in
domesticated species cases
where the wild
ancestor breeds once,
but the domestic domesticated
version breeds multiple times.
Now they're beginning
to see a slightly
longer reproductive season
in the domesticated females.
They were also beginning to
see all sorts of strange things
in their coat
coloration-- another trait
in the domestication syndrome.
In particular, there was this
strange star-shaped pattern
that was becoming more
common on the foreheads
of the elite domesticated foxes.
And if any of you
are horse fanatics,
you know that there are
breeds of horses where
you see the same
thing, and this is not
uncommon-- this strange
star-shaped, white pattern
on the forehead.
It's not uncommon in
domesticated species.
Now it's in the domesticated
foxes, and so on--
many, many more
changes by this time.
So at this point, they
decide that they're
going to expand the
experiment even further.
So they've got this line--
the domesticated line--
where they choose the
10% that are friendliest.
They have a control line,
where they choose them
regardless of how they
behave towards humans.
Now what they're going to do
is have a third line, where
they choose the 10% that are
most aggressive towards humans,
not because they're interested
in aggression per se,
but because I think that having
this new part of the experiment
will let them understand their
domesticated foxes better.
And that can happen
in lots of ways.
So for example, you
could breed the foxes
from the domesticated line with
those from the aggressive line.
And when you study
their pups, you
can get some hints about
underlying genetic change.
But I want to focus on another
reason that they did this,
and that is that
this whole experiment
that we've been talking about--
it's an experiment
in behavior, and it's
an experiment in genetics.
It's an experiment in
behavioral genetics.
And any time you
do an experiment
in behavioral genetics where
what you're selecting on
is behavior, you're always
worried about something,
and that is that maybe
non-genetic factors are
influencing your results.
So over these 15
years, we talked
about all the things they've
been finding in the foxes,
and their underlying assumption
has been all of these things
are due to changes
at the genetic level.
But maybe non-genetic
factors are playing a role.
Classic non-genetic
factors might be something
like pups learn, whether it
be friendly or aggressive,
by watching their
parents or other adults.
Another classic
non-genetic factor
would be the
hormones that you're
exposed to during development
might influence whether or not
you turn out to be
aggressive or calm.
And the only way to know whether
these non-genetic factor play
a role is to design
an experiment.
This is often referred to
as a transplant experiment,
sometimes referred to as a
common garden experiment,
except what we're
going to be looking at
is a common garden experiment
where the garden is
the uterus of a pregnant fox.
So here's what Lyudmila did--
she had five or six
pairs of females.
Each pair was made up
of an aggressive female
and a tame, domesticated female.
And both females were
pregnant, and the transplant
that's going to happen
happens when they're
about one week pregnant.
Even though no one had ever
tried this in an animal
this big, Lyudmila learned a
detailed surgical procedure
so that she could swap
developing embryos
from one uterus to another.
So here's what the
uterine horn of a fox
looks like when
they're pregnant,
and you can see that
they're carrying about 6
or 7 developing embryos.
What Lyudmila did
was she took half
of the developing embryos--
one week old-- from
the aggressive fox
and moved them over to
the uterus of the tame fox
and took half of the developing
embryos from the tame fox
and put them over in
the aggressive fox.
This is the classic experiment
you do to determine whether
what you're seeing is due to
genetic factors or non-genetic
factors because what
you do is you wait--
about eight weeks in this case--
till the females give birth.
Then when the pups are
up and moving around,
what you do is you
immediately see
how they behave towards humans.
And you look to see--
do they behave like
their genetic mother
regardless of what uterus
they happen to be raised in?
If they do, that tells you that
the changes you're looking at
are genetic.
If they behave like
their foster mother,
then that suggests non-genetic
factors might be at play.
So Lyudmila sets this up.
She's waiting,
but of course, she
has a little bit of a problem.
The problem is, when she moves
the one-week-old developing
embryos from one uterus to
another, she knows who is who.
But how is she going
to know who is who
when the females give birth?
Fortunately, she thought
she thought about this
and recognized this problem
before she did the transplant.
The foxes can provide you
the answer to that question
because fox coat color is a very
well understood genetic trait.
That means that Lyudmila
could color code the parents.
So in some treatments, the
domesticated female and male
had light fur color,
and the aggressive pair
had dark fur coloring,
and others vice versa.
And she then knew by the
coat color of the pups
who their genetic parents were.
OK, so she's waiting,
and she's waiting.
And at this point, I just
want tell you quickly
about another group
of people involved
in this experiment--
the people that Lyudmila
and all the scientists refer
to nicely as the workers.
So anytime you have
700 foxes on a farm,
someone's got to feed
them, change their cages,
make sure they're OK.
These are the
workers, and they tend
to be poor women
from local villages.
They don't understand the
details of this experiment,
but they know that
what's going on here
is really important science.
And they often go way
above the call of duty
to work with Lyudmila.
And it was the workers who
first discovered the females
giving birth.
They ran to Lyudmila's
office with cake and wine
and had a giant party
to celebrate it.
So what do they find?
I'm going to show
you the results
from one aggressive female, who
gave birth to a bunch of pups,
OK?
The results are very
similar across all females,
but I'm going to let
Lyudmila, in her own words,
tell you what she found.
So Lyudmila says,
"It was fascinating.
The aggressive mother
had both foster offspring
and her genetic offspring."
Of course, that is
exactly the way Lyudmila
set up the experiment.
"Her foster tame offspring
were barely walking,
but if there was a
human standing by,
they were already rushing
to the cage doors,
wagging their tails, and
also licking her hands."
Lyudmila continues,
"She, the mother,
was punishing her foster
tame offspring for such--"
I love this phrase--
"improper behavior.
She growled at them,
grabbed their necks,
threw them back into
the corner of the cage."
And what did those
little pups do
but get up, walk back
over to the cage,
and start licking
Lyudmila's hand again?
They behaved exactly like
their genetic mother,
not like their foster mother.
OK, so Lyudmila continues.
Now she's going to look
at the genetic offspring
of the aggressive mother.
What did they do?
And again, I adore the way
that she describes this.
"They retained their dignity,
growling aggressively--
the same as their mother--
and running to their nests."
They behave like
their genetic mother.
This was common for all the
pups born to aggressive females,
and it was also common
to all the pup born
to domesticated females.
The pups behave like
their genetic mother.
OK, so the experiment's going
on, and what's happening
is happening even faster than
Lyudmila and Belyaev dreamed
it would.
So at this point,
Lyudmila goes to Belyaev
with an audacious idea.
She says, there is
this tiny little house
on the experimental fox farm--
about 700 square
feet or something.
I want to move in there with
one of the elite domesticated
females and live with that
individual 24/7, the way
that we live with our dogs--
more importantly, the
way that our ancestors
lived with protodogs.
And I'm going to take notes
on everything that happens,
and we can really
see just how far
down the path of domestication
these foxes have come.
Yes, it's only a
sample size of one.
It's an anecdote.
But maybe it'll teach
us something important.
So Belyaev says, I love it.
And Lyudmila has the
perfect fox in mind.
The fox's name is
Pushinka, which
means "tiny ball of fluff."
And from the time that Pushinka
was three weeks old and walking
around, she was the
friendliest of all
the elite domesticated foxes in
the history of the experiment,
and Lyudmila knew
she was the one.
But Lyudmila decided
she was going
to wait a year until Pushinka is
ready to breed at one year old.
And she breeds Pushinka
with an elite male,
and now the idea is
that she is going
to move in with Pushinka
right before Pushinka
is ready to give birth
so she can take notes,
not just on what
Pushinka does, but what
pups who, from the
moment they're born,
are interacting
with humans the way
that we interact with dog pups--
how they act.
This is the only known
picture we have of Pushinka--
Belyaev petting her.
This is what the experimental
house looks like today.
It still stands even though this
experiment is in the mid-1970s.
But if you look inside
today, it's pure rubble.
And the reason that I'm
showing you pure rubble
is that, the first time that
I visited in January of 2012,
it was about minus 35.
The snow was about up to here.
Lyudmila is about up to
here, and nevertheless,
at 80 years old, she insisted
upon taking me out to the house
and giving me a room-by-room
tour, telling me,
this is where Pushinka used
to lie on the edge of my bed
at night.
This is where the pups
used to play ball,
and so on, and so on.
So they moved in.
And on April 6, Pushinka
gave birth to her six pups,
including this
little guy, Pushok,
which is the male version
of "tiny ball of fluff."
And she took notes on
everything that they did.
So this was April, and they
had been living together
for about three months,
so it's now July.
Now, this picture comes from
when I was there in the winter,
but in the summer, in July,
it's really hot in Siberia.
It can get to be 90
degrees at night.
And so what Lyudmila
would do every evening is,
on the other side of this
house, there's a little bench.
And she would sit out
there reading a book.
And like you might
with your dog,
Pushinka would be
lying by her side,
and Lyudmila would be
reading and petting Pushinka.
And every evening,
around 7:00 PM or so,
there was a guard that would
come around the fox farm just
to make sure everything was OK.
And they had hired a new
guard that nobody knew.
And this guard, on the
night of July 15th,
was approaching Lyudmila and
Pushinka in a sort of brisk way
that maybe you might interpret
as slightly aggressive.
And Lyudmila looked
down at Pushinka,
and she could not believe
what was happening.
Pushinka had bolted up, charged
towards the nightwatch person,
and began barking at them
exactly the way that a guard
dog would, and
exactly like no fox
in the history of the
experiment had ever barked.
And Lyudmila's first thought
was, Pushinka is protecting me.
But then she stopped
and said, wait a minute.
I know better than
most how dangerous
it is to fall into
that trap to think
that animals are behaving the
way we would in that situation.
But then something
else happened,
which was that Lyudmila
went over to the watchperson
and began talking to them
in a very calm, serene way.
And when Pushinka saw
that, she stopped barking,
walked back over to
the bench, lay down,
and waited for Lyudmila to
come back and start reading.
Is it possible Pushinka
wasn't protecting Lyudmila?
Of course, it's possible.
But what Lyudmila wanted
to know with just how far
down the path of domestication
these animals had come,
and Pushinka told her that.
And because you become
responsible forever
for what you have tamed,
Lyudmila would tell you,
from that night
forward, she knew
she would never leave the
experiment, and she never has.
So let me just take five more
minutes to quickly run you
through some other incredible
things that have gone on
in this experiment.
I mentioned before
that, in the '70s,
the reproductive season
of domesticated animals
were slightly longer-- another
trait in the domestication
syndrome.
In the early '80s, something
remarkable happened.
In about '84, a handful--
maybe four or five of the elite
domesticated foxes--
were ready to breed
twice in a year, not
only in the typical
January, February time,
but a second time in September--
absolutely unheard of ever
in foxes, but typical
for domesticated animals.
Lyudmila bred those
handful of elite females
with a handful of elite males
who would breed with them.
They produced a
second clutch of pups.
Think about how
radical the change has
to be in a reproductive
system to be
able to go from breeding just
once a year to twice a year,
all as the result of selection
on behavior and only behavior.
By the '80s and
'90s, Lyudmila was
working with people who had
very sophisticated equipment
that allowed her to measure
their faces and bodies
of her domesticated foxes.
And what she found was
a couple of things.
First of all, the
domesticated foxes
have a rounder, shorter,
more dog-like snout.
If you think of a
fox in the wild,
you think of this long,
pronounced snout--
domesticated foxes-- more
dog-like, round, short.
Another thing you might think
of with domesticated foxes--
another thing you might
think of with wild foxes
is they have these gracile limbs
that they're running around on.
The domesticated foxes
are chunkier and lower
to the ground than
wild foxes are.
So as the experiment
progresses, and we
get into the era of
molecular genetics,
they begin looking
at these questions.
And what happened was
there was a geneticist
by the name of Anna Kukekova,
a Russian geneticist,
who had worked with dogs.
And she approached Lyudmila
because now the tools
for studying genetics in dogs
are easily adaptable to foxes.
And she said, do you want
to do some work trying
to understand the underlying
molecular genetic changes?
And what Anna learned, which is
what everybody learns when they
work with Lyudmila, which is
that, if she thinks that you
can help her better understand
her domesticated foxes,
she will not only
work with you, she
will work with you in a way
that will make your head spin.
And before she knew it, Anna
had hundreds of blood samples
that allowed them to
start doing analysis
of the underlying molecular
genetic changes that
have occurred in their foxes.
And they've done this in
many, many different ways.
I'm just going to show you one--
an early study.
So one of the first questions
they asked was this--
there are all these
changes that have happened
with domesticated foxes--
not only they're calmer,
but all the morphological
changes we talked about-- the
floppy ears, the curly tails,
and so on.
The first question was, at
a molecular genetic level,
are the genetic changes
associated with that--
are they kind of spread all
over the genome of the foxes,
or are they localized in sort
of hotspots of genetic change
associated with domestication?
What they found was
many-- not all, but many--
of the changes in their
domesticated foxes
could be localized
to one chromosome--
fox chromosome number 12.
That's sort of
interesting, right?
It's not spread all
over the genome.
It's in a hotspot or in one
of a couple of hotspots.
More interesting was
that, at the same time
they were asking that
question, a group of people
were asking the same
exact question in dogs.
So dogs have more
chromosomes than foxes,
but fox chromosome
number 12 is essentially
spread across-- bits
of it are spread
across three dog chromosomes.
For anyone who's
a biologist, these
are homologous chromosomes.
But basically, fox
chromosome 12 is divided up--
bits of it-- onto
three dog chromosomes.
Lo and behold, one of those
three dog chromosomes, again,
is a hotspot for domestication--
changes associated
with domestication.
So even deep down at the
molecular genetic level,
it looks like they're
mimicking the process that
happened with wolves to dogs.
OK, last example--
I'm going to tell
you about one trait
that they have only found
in the last 15 years.
And this may be my
favorite of all the traits
that the domesticated
foxes have.
But before I tell
you what it is,
I want to tell you
why it's my favorite.
It's a couple of reasons.
First of all, this trait did not
appear till about 15 years ago.
So that means the experiment
was going on 45 years
before this trait emerged,
making it the poster
child for why long-term
experiments are important.
If any one of us had
worked 30 years on a given
biological system, we
would sit back and start
getting lifetime
achievement awards,
and you would not have worked
nearly long enough in a system
for something like this.
The second reason I
love this trait is it's
hard to imagine a
more perfect trait
for a domesticated pet-like
species to have than this.
So here's the story.
In about the early
2000s, a woman
by the name of Svetlana
Gogoleva approached Lyudmila.
And Svetlana studies
animal communication.
And she said, I
want to come there.
I want to study the sounds
that your foxes make.
And I want to study it in the
domesticated foxes, the control
foxes, and the
aggressive foxes--
see what we might find.
Lyudmila said, great.
Svetlana started coming
year after year-- ended up
with 2,000 hours of tapes of
the sounds these foxes make.
And what she found was,
across all the foxes--
domesticated, control,
and aggressive--
there are about eight different
unique sounds they make.
Most of those sounds
are made by foxes
in all the groups--
domesticated, control,
and aggressive.
But there were two-- and I'm
going to focus on one here--
that are only made by
the domesticated foxes.
And the one that we're
going to hear in a second--
this is only made by
domesticated foxes.
It's made by almost all of them,
and it's made from the time
that they start walking
around, and this
is what it sounds like.
[FOX LAUGHING]
LEE ALLEN DUGATKIN: There
is no non-human sound
that's closer to human
laughter than that sound.
If you put it on a
spectrogram and look at it
and compare it to
human laughter,
there's no sound that's
closer to human laughter.
And it's almost
too perfect, right?
I mean, now you have an animal
that is not only incredibly
friendly and incredibly
cute, but you
have an animal that's
going to laugh with you
when you're laughing,
and it's going
to laugh with you
when you're angry,
and it's going to laugh with you
when you're crying because it
doesn't care about any of that.
But nonetheless, it's making
this perfect sound, right?
And so it's just what
you'd want to have
in a domesticated species.
OK, so if you talk
to Lyudmila 60 years
after she began and continues
to work on this experiment,
and you ask her about our hopes
and dreams for the future, what
you'll get is-- well, you'll
get a six-hour answer,
but I'll give you
the quick version.
The first thing
she'll tell you is I
hope it's possible to register
them as a new pet species.
So technically, they are
considered an exotic species.
There are, in fact, a couple of
dozen in people's houses across
the United States and Europe,
but because they're-- and
they're very expensive,
and all the money goes
to the experiment.
But because they're
an exotic species,
the rules about whether
you can have one of these
vary, not just from country
to country and from state
to state, but from city to city
and subdivision to subdivision.
Now, there is an
international panel
that can assess whether an
animal should be considered
a house pet, and they're working
to get that classification.
Once they do, then the foxes
could go into houses anywhere.
And what Lyudmila
envisions is they
have plenty of foxes to
keep the experiment going
and also to put a few
hundred into people's houses
every year.
The other thing that Lyudmila
will tell you about her hopes
is, one day, I'll
be gone, but I want
my foxes and the
experiment to live forever.
I do.
I hope you do, and I appreciate
you guys taking your lunch
to hear this talk.
Thanks very much.
[APPLAUSE]
AUDIENCE: So in
anthropology classes,
you hear about this nonstop.
So I'm curious--
LEE ALLEN DUGATKIN: Oh, really?
You hear about this experiment?
AUDIENCE: Oh, yeah.
LEE ALLEN DUGATKIN: Oh, good.
That's good to know.
AUDIENCE: It's part of the
curriculum [INAUDIBLE]..
I'm wondering when you
first heard about it
and how you got involved.
LEE ALLEN DUGATKIN: Well,
because my own degree
is in evolutionary biology, I
don't remember exactly when,
but it must have been in
one of my graduate classes
because it is a very
famous experiment.
I got involved in it
seriously about 10 years ago
when I was looking for a new
history of science project.
I had done some work on
Russian evolutionary biology,
so I knew not only about some
of the basic things they found.
See, the thing is,
a lot of people
know a little bit about this
experiment because 95% of it
is published in Russian.
So people know about floppy
ears and stuff, but not a lot.
So I knew a little bit about
the science, and I thought,
I know this is
important science,
but I also had a sense
that Lysenko was involved.
I had a sense that there
were some really interesting
human-animal bonding
stories and all of that.
So I approached
Lyudmila about it,
and she was keen
on doing something.
So I'd say 10 years ago.
And it's been great.
I mean, Lyudmila and that
whole group in Novosibirsk
have become like family.
And I just emailed
with her the other day,
and she's doing fine.
And she's still
leading the experiment.
Yeah, sure.
AUDIENCE: Thanks for the talk.
The foxes are adorable.
I'm curious if they
tried to control
for researcher's bias, like
would Lyudmila favor animals
that have that domestication?
LEE ALLEN DUGATKIN: Yeah,
it's a great question.
Right, and so this is
an inherent problem
in this kind of
experiment, where
you're going to gauge behavior.
So I think that, over the
course of the experiment,
they've gotten much better
and tighter about this.
Initially, like when I talked
about that place, Lesnoi,
it was really Lyudmila
and Lyudmila alone.
But once the experiment moved
in 1967 to the experimental farm
and there was a
whole team of people,
they began to do other
things that really
controlled as much as possible
for what you're talking about,
OK?
So first of all, the
key thing they do
is they've adopted
techniques that
come from psychology
because psychologists
have this problem all the time.
You're measuring
behavior, and how do you
know you're only using
what you think you are?
Maybe you're being
affected by other things.
The classic way to do this is to
have multiple different people
independently assess whatever
is being looked at and then look
for type correlations across
people in terms of who says
the animal is friendly
and who isn't.
And that's what they do now.
The other thing that
they do is that there
are many, many components
of behavior that they're
looking for, not just the
four things that Lyudmila
talked about early on.
The core of it is they're
still looking for attributes
of friendliness towards
humans, but they've
subdivided that into
dozens of different things.
So that plus the
multiple observers
is the classic way to
handle this problem,
and they do the best
they can with it.
AUDIENCE: Thank you.
LEE ALLEN DUGATKIN: Yeah.
AUDIENCE: Just same question.
LEE ALLEN DUGATKIN:
OK, same question?
OK.
OK, yeah, sure.
AUDIENCE: First of all,
thanks for the talk.
LEE ALLEN DUGATKIN:
You're welcome.
AUDIENCE: I was
wondering, in your words,
you said that this happened
sort of in the blink of eye
on an evolutionary scale.
Is that something
inherent to foxes
or how quickly they
reproduce or to some larger
classification of animals than,
like, if you selected something
from a totally different,
not related at all
to foxes or wolves--
what would that be?
LEE ALLEN DUGATKIN: Yeah,
it's a great question.
And we know the
answer to some extent
because, on the other side of
the farm where the foxes are,
are hundreds and
hundreds of mink.
And for the last 40
years, another person
has been running the exact
same protocol on mink
and finding very
parallel results.
So they're smaller animals, so
they're not quite as dramatic
and sexy as what
happens in the foxes,
but if you choose on
behavior and behavior alone--
and they've done that both
domesticated and aggressive
like with the foxes--
you not only get
behavioral changes,
but you get changes
in coat coloration,
hormone levels, juvenilized
facial patterns--
all of that same sort of stuff.
I will tell you that, as
scary as the foxes that
have been bred for aggression
are, the minks that
have been bred for aggression--
I still have nightmares
walking by those cages.
I mean, they're demonic.
And there's a third experiment
that started with their group
but then migrated to
one of the Max Planck
Institutes in Germany, where
they're doing essentially
the exact same thing in rats--
and again, smaller animals, so
not as dramatic, but same basic
results.
Select on behavior--
you get, not
just changes in
the behavior, but
the morphological,
anatomical, hormonal changes.
AUDIENCE: How about in, like,
the number of generations--
was it sort of like
a similar timeline,
or did it take much longer?
LEE ALLEN DUGATKIN:
Yeah, I mean,
so the mink too
breed once a year,
and I think they
were beginning to see
serious changes within a
couple of dozen generations
like the foxes.
Now, you have to remember
also that this is--
I mean, it's hard
to say anything
about the absolute
amount of time
and how important that
is in the domestication
process in the wild only
because this is really
super intense selection.
You know, you're just
using the top 10%.
In evolutionary
history, our ancestors
would not have been
doing that kind of thing.
And initially, it would have
been unconscious selection--
just sort of the ones that
came closest were the ones that
were friendliest, and so on.
Then, when they started
doing it consciously,
it would not have
been to the intensity
that we're talking about here.
AUDIENCE: Thank you.
LEE ALLEN DUGATKIN: Sure.
AUDIENCE: So one
thing that you kept
bringing up in this
presentation is
that these specific domesticated
behaviors that these foxes
acquire are dog-like behaviors.
And I know that there
is some relationship--
I'm not sure how close it is--
but are there differences
between the two
that still persist,
and how close are they
really after domestication
in this form?
LEE ALLEN DUGATKIN:
Well, I guess
you can answer that at a
couple of different levels.
First, they're both
canines, right?
So they have a shared
evolutionary history.
But their most recent
common ancestor
was on the order of
12 million years ago.
But they're all canines.
I use the language
of "their behavior
is very dog-like" as a
way to sort of put it
in context, meaning they
lick hands, they wag tails,
and so on.
In that sense, they
are very dog-like,
but in many, many other
ways, they are not.
So they are not animals that
are inherently gregarious.
They don't necessarily--
they're not animals
that like to live in groups.
There are many, many differences
between the domesticated foxes
and dogs, but there
are a tremendous number
of similarities that seem
to be due to choosing
for this pro-social behavior.
I mean, at the genetic level,
although the underlying changes
like we talked about
have been similar,
you couldn't breed them
or anything like that.
AUDIENCE: Right.
I guess, I don't
want to hold up,
but I would have
also asked how far
away are we from speciation?
LEE ALLEN DUGATKIN: Yeah,
that's a good question.
And the answer is
very far, I think.
So the aggressive foxes
and the domesticated foxes
can breed perfectly well.
They do it all the time to
understand the underlying
genetics.
They've never attempted
anything with wild foxes
because they're terrified
of introducing rabies
and all this sort of thing.
But there's no
reason in the world
to think that they
wouldn't breed
perfectly well with wild foxes.
So, so far, there's not
reproductive barriers.
But again, this is 60
years, which is nothing.
If they ran the experiment
for another 500 years,
would there be differences?
Maybe.
Even that's a small amount
of evolutionary time.
But we don't know.
AUDIENCE: Thank you.
LEE ALLEN DUGATKIN:
You're welcome.
AUDIENCE: Hi, I was wondering
what the lifespan of the foxes
are and if it changed when
they were domesticated.
LEE ALLEN DUGATKIN:
Another good question.
So believe it or not, we
don't know a tremendous amount
about the lifespan
of wild foxes.
People estimate it at maybe, you
know, on average, two or three
years.
But then all the
foxes on the fox farm
can live six, seven years.
Now, but in terms
of differences,
there are no differences between
the domesticated animals--
the domesticated line,
the aggressive line,
and the control line.
So one of the changes has
not been longer lifespan.
They have slightly more
offspring, but not longer
lifespan per se.
Yes.
AUDIENCE: Hi.
LEE ALLEN DUGATKIN: Hi.
AUDIENCE: Of course,
this experiment
has never run for humans.
LEE ALLEN DUGATKIN:
Oh, I'm glad you're
going to ask what
you're going to ask.
Go ahead.
AUDIENCE: Right, I mean, once
you dedicate your whole life,
I'm sure she had some great
observations on humans.
I wonder if she ever
exchanged any stories
with you or any observations.
LEE ALLEN DUGATKIN: So we do
talk about this a little bit
in the book.
So here is the short version.
In the late '70s,
Belyaev, her mentor
and the person who basically
was her go-to person
on this experiment,
Belyaev hypothesized
that human evolution was an
example of self-domestication.
And the self-domestication
idea is this--
instead of some external force
choosing the animals that
are friendliest or calmest,
in self-domestication,
that happens by mate choice.
So the idea was, in
evolutionary history,
both males and
females would have
been more likely to
choose calmer, more
cooperative mates, right,
for all sorts of reasons.
First of all, interpersonal
aggression would be minimized.
And also things that
require cooperation
would have been maximized.
And the argument,
then, is that, by doing
that, by selecting the
calmest, friendliest mates,
you are, in fact, mimicking
the process of domestication.
It's just self-domestication.
This was an idea that
Belyaev had in the late '70s.
Didn't really do a lot with it.
Just in the last three
months, Richard Wrangham,
a colleague of mine at
Harvard, has an entire book out
on human self-domestication.
And now there's evidence
from all different fields
to suggest that we may
very well be the product
of self-domestication.
And the evidence comes in
lots of different forms,
one of which is that,
if you compare--
oh, if you compare--
it says, wrap up, please.
I got it.
OK, I'm ready to stop any
time you guys are, right?
So you have to tell
me when to stop.
So one of the forms is that, if
you compare us to our closest
living relatives,
meaning chimpanzees,
we tend to show traits that
are more in the domestication
syndrome than
chimpanzees do, right?
We have longer
reproductive periods,
we have lower stress
hormone levels,
we have many juvenilized
features compared
to chimpanzees.
And there are many
other forms of evidence
to suggest that we have
self-domesticated ourselves.
I would suggest, if
you're interested,
Richard's book is called
"The Goodness Paradox,"
and it just came out.
It's getting a lot of attention.
You could easily
find it on Amazon
when you search for my book.
So there you go.
Thank you very much.
[APPLAUSE]
