Well, I knew it's a
hackneyed expression,
but today's speakers truly
do not need an introduction.
That's how we're not
going to stop me,
but I will keep it short.
Peter and Rosemary
Grant have conducted
what is arguably the most
famous and most important
study in the history of
evolutionary biology.
I refer of course, to
their 40 year research
program on the Darwin's finches
of the Galapagos Islands.
This study has produced
one major finding
after another that
has significantly
changed our understanding
of how evolution works,
including making important
advances in our understanding
of the pace of evolution,
the strength and constancy
of natural selection,
how new species arise,
and many other topics.
It is our great privilege
a privilege to hear more
about this work in
just a few moments,
but I want to say few
words about the Grants.
Peter Grant did his
undergraduate studies
at the other Cambridge
over in England,
before coming to North
America for his doctorate
at the University
of British Columbia.
He then did postdoctoral
work at Yale.
And I should note that in those
days, Peter was a mammalogist.
Rosemary Grant did
her undergraduate work
at the University of
Edinburgh, and received her PhD
from the University of Uppsala.
After spending
time in New Haven,
the Grants held positions
at McGill and Montreal
and the University of
Michigan, before moving
to Princeton University
in 1985, where
they have been ever since.
Now I don't have enough time to
list all the awards and honors
that Rosemary and
Peter have received,
so I'll briefly give you
a few of the highlights.
They have been elected Fellows
of the Royal Society of London,
of the National Academy of
Sciences of the United States,
and of the American Academy
of Arts and Sciences.
They've won the Leidy medal
from the Philadelphia Academy
of Sciences, the Edward
O Wilson naturalist
award, the Grinnell medal of
the University of California
at Berkeley, the Darwin
Wallace medal of the Linnean
Society, the Balzan Prize,
and the Kyoto Prize.
In addition, the
University of Michigan
has created an endowed
professorship, the Rosemary
Grant Collegiate
Professor of Ecology
and Evolutionary Biology.
The Society for the
Study of Evolution,
the leading international
organization
for the Study of Evolution, has
created an award in recognition
of Rosemary's work in mentoring
young students, the Rosemary
Grant Graduate Student
Research Awards, which
are given out annually.
Well, today we're fortunate to
have a double, double header.
What I mean by that is for
the first half of the evening,
we are going to hear Peter
and Rosemary speak separately.
Each of them will speak
for a few minutes.
Then we'll take a very short
break, and Peter and Rosemary
and I will have a conversation
up here about their work
and about evolutionary biology,
after which we will take
questions from the audience.
Well, with that I'm
delighted to introduce
Peter and Rosemary Grant,
and we'll start with Peter.
Thank you Jonathan, very
much for that very nice
introduction.
And also for the
invitation to come here
on this splendid occasion.
Very exciting, and you have
an excitement that in a way,
I know I have an excitement
that you do not share.
But I will try to
share it with you.
I'm not sure how I
operate this machine here,
so I hope you'll come forward to
the edge of your seat and hope,
like me, that everything is
going to work as I want it to
by pressing the right button.
Now between about one and 1/2
and two million years ago,
a flock of finches arrived
on the Galapagos Islands.
And now there are
at least 14 species.
And as evolutionary
biologists, Rosemary and I
would like to know
how to explain
that multiplication of species
from a single ancestral
individual species.
It's a kind of fundamental
evolutionary question
that many biologists-- some of
whom are in the audience now--
address with a
variety of organisms.
In 1973, we decided to
address that question
by visiting Galapagos and
starting on a research
program that began an
archipelago-wide level,
and zeroed in
increasingly on the system
of this little
island, Daphne major,
in the middle of
the archipelago.
It is about 3/4 of kilometer
long, 120 meters high,
and it's never been
settled by humans.
And what I'd like to do
is to share something
of the experience of
being on the island
by showing you little
clips of video material.
Rosemary and I have made six
videos for educational purposes
that we have licensed Pearson
Education and the Films Media
Group to show on their
respective outlets.
So you're going to see--
if this works properly,
you're going to see
little clips to illustrate
the various points that I
would like to make by way
of introduction of our talk.
And so with that, let's try.
As I say, wish me luck on this.
Daphne is in the center
of the archipelago.
Right in the middle, there is
a crater where sea birds nest.
It's a tuff cone.
It was formed underwater
about 20,000 years ago.
And it has a
variety of habitats.
The key to understanding
how finches
can live in an
environment like this
is an underappreciation of the
strong seasonality in rainfall.
So in a normal year,
Galapagos receives
rain any time between
January and April or May,
and nothing for the
rest of the year.
And so in a normal dry season,
there's no production going on.
And in some years, there's
no production going on
because there is no rain.
And here is a scene from the
inner wall of the crater that
could be just as easily taken
from the dry season of one
year as a dry year.
There is a strong challenge
for birds to find enough food.
The opposite is true in
seasons where rain falls
and in particular, in
years of El Nino, where
an abundance of rain falls
over a period lasting
from four to eight months.
And then the finches
breed for as long as that.
So I would like to
give you an idea what
it's like to be actually
on the island working,
by describing our normal routine
of getting to the island.
Then after that,
as I said before,
we'll say something
about what we
found by studying the finches.
So we'll get our supplies at
the Charles Darwin Research
Station, put them into
quarantine for 48 hours,
and then load them
onto a boat which
delivers us to this little
island within one day.
Once we're on the island,
once we've reached the island,
we have to get ashore
and unload our belongings
and lift them up
a four meter cliff
in order to then
transport them to where
we will establish camp.
And the "them" refers
to scientific equipment,
camping equipment, water,
food, and anything else
that we need for
field season, that
lasts anywhere between three
weeks and several months.
Like everything else
we bring to the island,
these metal boxes have
been in quarantine
and would be used
to store our food
for the period on the island.
But before we put
the food in that
is brought in other containers,
we check these metal boxes
for fear that we might have
introduced alien insects
or seeds.
The kitchen is in a cave.
On the left is the stove.
In the center on the
right on the screen
here, is a large
container where water
is filtered underneath a
large green plastic bag that
serves to exclude sunlight.
On the right is
another box not shown
in this picture,
where we store all
of the scientific equipment,
binoculars, tape recorders,
cameras and the like in
other white metal boxes.
There's no fresh
water on the island.
Fresh water is our
lifeblood, and we
have to bring it in 30 large
plastic containers, which
with a built-in safety margin,
should be enough to last us
for about a month.
And then after that,
we get resupplied.
All clothes that
need to be washed,
all the dishes that
need to be washed,
ourselves that need to be
washed-- all that washing
has to be done in the sea.
So part of the daily
routine of our lives
is to go back to
the landing where we
arrived, and collect seawater.
Then I should mention
finally, in this tour
of the living conditions of
the island where we camp,
there is only one place on
the island to put a tent.
That's on the outer slope.
The center part of
the island, the crater
is occupied by sea birds,
and we shouldn't be
interrupting their activities.
Now to understand
the finches, we
need to capture them, we need
to measure them, band them
with unique combinations
of bands on their legs
so that we can release them and
recognize them as individuals,
and then watch what they do and
quantify, study and quantify
their activities,
including their survival.
So putting out mist nets
which many ornithologists do,
is a key activity in
our scientific program.
And like ornithologists
elsewhere, we
do the usual thing of
capturing them early in the day
typically, remove the
birds from the net,
disentangle their heads,
necks, wings, and beaks as well
as a claws, and then put
them into light cloth bags.
And then we take them
up to a shaded cavelet,
where we then start to
measure and band the birds.
Banding begins with a
numbered metal band that's
placed on one of the legs.
And then we add three
colored plastic bands
made of PVC plastic.
The colors are coded to
correspond to the numbers
so that when we
release the bird,
we'll be able to see
just by the colors
alone what the number of
that bird has been assigned.
So for example, black
is coded as zero
and yellow is coded as nine.
So we measure them, as
I've mentioned here,
we put the bands on.
And then we put the bands
on in a particular way, such
that the band is above the
color on one leg for one
species, Fortis,
and below the color
for another species, Scandens.
The colors are
actually recorded,
but the numbers are read
from upper left position
on the left leg to the lower
position on the right leg.
Then after the banding,
Rosemary takes the bird
and with a fine needle,
pricks the wing vein
and takes a small drop of blood;
transfers it to a filter paper
and then stores it
in a jar of drierite,
having labeled the
paper, and placed
into some cool area,
typically a cave,
to keep the temperature
as low as possible.
It's a procedure
that we humans used
for getting blood typing
rather, of newborn babies.
It's exactly the same
process that we use.
And then we release the bird
and that we watch what they do.
Another key activity
is finding nests.
So when we found the nest,
we flag a nearby bush
so that we could
recognize where it is
and go back to it
to find it again.
And then when the time is
ready, we band the nestlings,
and then later, we measure them.
Similarly, we take blood
samples for DNA analysis.
And by that means,
we could build up
an inventory of relatedness
through pedigrees
across generations of
grandparents, parents,
offspring and so forth.
There are three species
of birds on the island
and the commonest is this
one, the medium ground finch,
which is by the ground
finch genus Fortis.
There are two others.
One is Magnirostris, the
other one is Scandens.
The first being the large
ground finch, this one
being called the cactus finch.
Medium ground finch feeds
on small seeds on the ground
and on low herbs, and
it has a small beak.
Magnirostris has a
much larger beak,
which it uses to crack open
the large and hard seeds
of a plant known as Tribulus.
Scandens, the cactus
finch, has a pointed beak
and this is a tool that
it uses for probing
cactus flowers, Opuntia
cactus flowers for nectar,
for pollen, and then
for later, getting out
the seeds by hammering a hole
in the sides of the fruits.
So a key difference
between these species
is their diets in the dry
season, when food is scarce.
And that is associated
with a difference
in beak size and beak shape.
And so the evolution question
is how does a beak size or shape
evolve, and how do the
differences between the species
evolve?
Well, a drought in
1977 gave us an answer,
when four out of every five
members of the medium ground
finch population died as
a result of starvation.
We had banded a
very large number
of them entering the drought.
And so we knew from that
that the ones that survived
were particularly large,
particularly especially
in beak size and beak
depth is the dimension
that I'm illustrating
here in this diagram.
Beak size on average,
increased over the whole
of the drought of
1977, stopped only
when the rains resumed in 1978.
And the reason for this
differential survival
was the ability of birds
with large and deep beaks
to crack open the hard
seeds of Tribulus.
You see in the top
left hand corner
an illustration of the fruit.
It's a woody fruit, hard
and difficult to crack open.
Small beaked birds,
having depleted
the supply of an
abundant small seeds--
having depleted that
supply, could not
open the Tribulus, whereas the
large beaked birds could do so.
They survived, and as a
result, natural selection
with an advantage going to the
large beaked birds occurred.
The net result was an
increase in average beak size.
And because beak size
is a heritable trait,
evolution took place from
one generation-- this one,
the one subjected to
natural selection,
and the next generation,
the generation of offspring
produced by the survivors
in the following year, 1978.
We also discovered that
evolution by natural selection
occurs as a result of
competition between species.
This happened in a
rather extraordinary way.
In 1982, '82 to '83, there's
a very severe El Nino event.
An abundance of rain.
And the large ground
finch species,
in spite of Magnirostris,
colonized the island,
not having been a breeding
member of the community up
to that time.
Two females and three
males stayed to breed,
and they produced 17
offspring, most of whom died.
But in successive years, that
population gradually built up.
So by the time of the next
really intense drought in 2003
to four, and then
all into 2005, there
were at least 250
Magnirostris on the island.
Now they have much larger
beaks-- as you saw earlier,
than Fortis.
And so with that
large equipment,
their capable of very
much quicker cracking
of the fruits of Tribulus
down here in the bottom right,
than the large beaked Fortis,
which are in the top left
illustrated there.
As a result of that
differential efficiency,
Magnirostris survive better
than Fortis with large beaks,
large beaked Fortis died
to a very large extent,
a rapid extent.
Now, small beaked
Fortis, bottom left,
were also dying
at the same time.
But dying at a slower rate.
So there was a selective
shift towards on average,
a smaller beak
size in over here.
And because the beak size
is a heritable trait,
to say it once again,
evolution took place
from that one generation that
was a selected generation,
to the next one, the
offspring generation.
And remained low thereafter.
Evolution by natural selection
had occurred once again,
and as a consequence, the sizes
of Fortis and Magnirostris
diverged.
So these results illustrate
two major factors
responsible for the
diversification of the finches.
Not just here on this island,
but we think more broadly
in the archipelago.
One is a fluctuating
food supply,
the other one is
competition between species
for food in short supply.
But they're not
the only factors.
So Peter has shown you
how beak size changes.
What I'm going to
do is to tell you
how a severe El Nino event,
how this severe event in 1983
led to a change in beak shape.
And then I'm going
to tell you about one
of the most exciting
parts of our study,
which is the formation
of a new lineage, which
we were able to follow
from its inception
up for six generations.
But first of all,
this severe El Nino.
This occurred as Peter
said, in 1982 to 1983.
And it was from Concord Data the
most severe event in 400 years.
It brought an enormous amount
of rainfall to the islands,
and also to this little dry
desert island of Daphne,
which received over
a meter of rain.
It completely altered
the ecological conditions
of the island, changing it
from a large hard seed producer
to a small soft seed producer.
And rather than show you
all our quadrant data
or boring numbers,
it was so obvious
that I can just use
pictures to show this.
This is part of the island
showing a normal dry season.
And you can see that there
are no leaves on the trees
as you would expect,
and the ground
is made up mainly of rocks.
Now a normal wet year,
leaves come up on the trees
and then little herbs
grow up through the rocks.
And most of these plants
are Tribulus plants,
producing these large
hard seeds which
made the difference between
survival and non-survival
in the first natural selection
event that Peter showed you.
But in this year,
the rain continued.
Grasses and other
plants grew up,
all small seed producing
plants, completely
smothering the Tribulus plants.
More rain fell, and then
vines started to grow.
They grew up over the cactus
bushes and also over the trees,
and completely
smothered the island.
And then even the
year afterwards,
after the rain had
stopped, you could still
see the remnants of
the vine-draped cactus
bushes and trees on the island.
And the abundance
of seeds were now
small seeds, rather than these
large hard Tribulus seeds.
And the season
seed bank remained
like this with
small seeded plants
producing more small seeded
plants for the next 30 years.
So with an abundance
of small soft seeds,
the rare hybrids that have
been forming between Fortis
and Scandens occurred about
1% of the birds being produced
each breeding
season, are hybrids
between Fortis and
Scandens, and they
have intermediate beak sizes.
But they were now
able to survive.
Before that, they'd not
been able to survive
because their beaks
were not appropriate
for the large hard seeds which
were the predominant seeds.
But now with a vast
amount a small soft seeds,
they were able to
survive to breed.
There were very few of them.
They didn't breed
with each other,
but they did back-cross
to one or other
of the parental
species, according
to another story about
how they do this,
but according to the
song type that they had
learned when they were young.
So Fortis and
Scandens, Scott Edwards
told you 2 times ago that
actually, you could hardly
tell the difference
between the finches,
but here's a slide where
I think you already can.
Fortis has this
blunt beak, Scandens
with its long pointed peak.
And the hybrids
were intermediate.
Now I'm showing you now a plot
of the depth of the beak length
and for the first 10
years of our study,
the longer beak--
for every dot in 1975
represents a bird that
was alive in 1975.
And you can see that the
population of Scandens
with the longer beak are clearly
different from the population
of Fortis.
But after this gene flow
between Fortis and Scandens,
the two populations
began to converge.
This started in 1983,
and by 1987, you
can see the beginning
of the convergence,
and it continued for
the next 30 years.
Now we were able to track
the genes because we
had genetic representatives
at this time, called
microsatellite loci, and
we were able to track
these genes going from one
population into another.
And when we did
this, we could look
at the difference between
the genetic difference
between Fortis and
Scandens before those
in congressional
gene flow, and then
follow it right through
the next 30 years.
And you could see that the
two populations, Fortis
and Scandens began to
converge on each other.
And then with our measurements,
our morphological data,
the morphology converged at the
same rate as you would expect.
Now if we actually
extrapolated this into 2057,
by that time if everything
was equal-- and I'm sure
won't be-- the populations
would be identical.
But the average beak
size of Fortis population
became much more Scandens-like
and became much more pointed,
and this the point where
it became more pointed.
This is the beginning
of integration,
and it continued this way
for the next 30 years.
And we'd already shown
with measurements
and watching them, that
the small pointed beaks are
more efficient at dealing
with the small soft seeds.
Now, just last year,
or two years ago
in the last couple of
years, we had actually
sent genetic samples over to
our collaborators in Sweden.
And they had found a
very important gene
called the ALX1 gene.
This gene is highly conserved,
both in birds and mammals.
And in fact, it is
responsible for what's
called transcription pattern.
It's responsible for the
cranial facial development.
And interestingly, a mutation
in the ALX1 gene in us humans
causes cleft pallet.
But in the birds in
the Darwin's finches,
it comes in two varieties
and the ALX1 blunt haplotype
is predominantly in blunt-beaked
birds like the Magnirostris
you saw and the Fortis.
And whereas the ALX
pointed haplotype
is in all the pointed
beak birds, like Scandens.
So we thought ah-ha.
So we sent our blood
sample the ALX1 haplotype,
so variants are probably
responsible or contributing
to the more pointed beaks
that we see in Fortis.
So we sent the
blood samples back,
we had them still in
the minus 80 freezer,
we got them out and sent them
over last year to Uppsala.
And sure enough,
that's what they found.
So the ALX1 pointed variant
was introduced from Scandens
into Fortis, and this
probably contributed
to Fortis' more pointed beaks.
Now genetic exchange
goes both ways,
there's gene flow from Fortis
to Scandens and Scandens
to Fortis, and just
as you would expect,
the average beak
shape of Scandens
became blunter and
more Fortis-like.
And in those populations,
the variation in size
was increased to a
really noticeable extent.
So all these photographs
were taken in 2012,
actually it so
happened because we
had the camera there
from the same net,
and they're all Scandens.
So at the top, the Scanden
was a pointed beak.
It is very similar
to the Scandens
before there was any
genetic introgression.
And these two Scandens
were the blunter
and more Fortis-like beak
after introgression are
most similar in the population.
So we have this huge variation
of Scandens and beak shapes.
So we argue that as a result of
genetic exchange between Fortis
and Scandens, the
population acquired
new genetic combinations, and
the genetic and phenotypic
variation, the appearance
of the birds increased.
And we'd argue that
if such birds flew
to another island with
different ecological conditions,
because of this huge
amount of variation
both genetic and
phenotypic variation,
it could be a possible
starting point
for new evolutionary trajectory.
And we never thought we
would actually see this,
but it did in this formation
of the new lineage of finches.
What happened was a bird
arrived on the island,
it looked like a Fortis,
but it was much larger.
It weighed 28 grams, whereas a
normal Fortis weighs 17 grams.
So considerably larger.
We caught it, we took
some blood from it.
And we tested it just to see
if it didn't confirm that the
hadn't been born on Daphne.
And we also looked at
its genetic profile
and checked it with all the
birds in the island around,
to try and find out where it
could possibly have come from.
And it seems to have
come from Santa Cruz,
and with about a
90% probability,
it was not a Fortis
from Santa Cruz,
but a Fortis/Scandens/Fortis
back-cross from Santa Cruz.
To our excitement, it
had a genetic marker.
It had an anneal
that was very rare,
one of our microsatillite loci.
And then when it
started to sing,
it had a completely
unique song, never before
been heard on Daphne.
But also to our puzzlement, had
never been heard on Santa Cruz.
It took ages to breed and when
it did, it bred first of all,
with a Fortis/Scandens/Fortis
back-cross born on Daphne.
And then it bred
with two Fortis,
and that was the only
out crossing it did.
Produced quite a large
number of offspring.
All these birds had at least
one copy of this unique anneal,
and they all sang.
We had banded this
bird 5110, and they all
sang this unique song.
And then along came the
two and 1/2 year drought
that Peter referred
to, and all these birds
died except for two.
These two are inbred
brother and sister.
These two brother and sister,
when the rains came again,
they bred with each other.
They've produced 26 offspring.
All but nine of them
survived, and so we
had terrific in-breeding with
the son mating with his mother
and the daughter with
her father, and the sibs
with each other to
produce more offspring.
All these birds had two
copies of this rare anneal.
All the males sang
this 5110 song
that had been passed down from
father, to son, to grandson,
et cetera.
And all were large, like 5110.
So from 5110, we had a
cultural transmission
of song and a
genetic transmission.
So is this new lineage behaving
like a separate species?
It's much larger than its
nearest relative, Fortis.
It's in morphilogical space.
It lies between on a plot
of bill and bill depth,
it lies between Magnirostris
in green and Fortis in blue.
And the population
lies just here,
which is in the gap
that became enlarged
in that last natural
selection event
that Peter told you about, when
the Magnirostris out-competed
the large Fortis for the
remaining large hard Tribulus
seeds.
It has a different song.
This is three generations of the
big bird's song, different song
from Fortis, Scandens
and Magnirostris.
It holds large territories that
are contiguous with each other.
The blue dots are territories
before the drought,
the red dots after the drought.
And these territories
overlap with Fortis Scandens
and Magnirostris,
who ignore them
and who are ignored by them.
So that's in all
respects, this new lineage
is functioning as
a separate species.
Will it die out through
inbreeding depression?
Well, it's surely
inbred, it might.
But we see no sign of it.
Will the genetic
variation be augmented
through genetic exchange?
Again, it might.
And this we think
is quite likely,
so we look very, very carefully
for this but haven't found it.
But whether it survives
or not, this new lineage
gives us insight into how a new
species could arise and either
persist, or become extinct.
So in summary very
quickly, we started
with two different
species, ended up
with Fortis and Scandens
intergrogressing Magnirostris
and the big bird lineage.
So we thank all our
many graduate students,
our post-doctoral fellows,
our collaborators,
and doctors, which
none of this work
could be done
without these people.
And also the Galapagos
National Park and the Darwin
Station for all the logistics.
But I would like
to-- just before I
pass this over to
Jonathan, I would like
to leave you with one message.
And that is all of
us who worked on
these islands are very
conscious that environments
and populations are dynamic,
they're constantly changing,
and to keep our environment,
we must keep them both capable
of further natural change.
Thank you.
Thank you Peter and Rosemary,
for that fascinating look
at how your research is
conducted and what you found.
The first question I have
is how did you get started?
What brought you to the
Galapagos in the first place,
and what did you
think you would find?
You want to go?
Shall I go?
I'll start and
people will fill in.
What brought us to
the Galapagos was
we were really very
curious about the process
of speciation.
And the Galapagos
has several things
that are an advantage
to look for this.
First of all, we knew they
had this environment that
swung from El Nino to La Nina.
And so we thought this would
be the most likely place
that we would be able to
find this sort of thing.
And then the other thing is
that it was a young radiation.
We had read David Lack's
book, we knew all about
that this radiation was possibly
a young radiation, where
there were 14 species that had
probably been derived from one.
And also, many of the
islands on the Galapagos
are completely pristine
or almost pristine,
never had any humans.
So any dynamic that
we were able to see
and that we could measure
would be a perfectly natural
situation.
So can you add anything?
I'll just add a couple
of things to that.
One is that there
are several species,
and it's often difficult to tell
the difference between two very
similar species, whether
they are on the same island
or a different island.
And as David Lack, our
predecessor pointed out
in a book in 1947,
this situation
looks as if it is one of
speciation taking place,
actually now in
contemporary time.
Most of the species
we see around here,
robins, starlings, in the
bird world for example,
are very clearly
different from each other.
They have been produced by a
process of speciation, yes,
but you're not likely
to see the process now.
But in the Galapagos,
one could possibly
see the very slight
changes taking place
from one to another.
So that was one
extra reason that
motivated us in going
there in the first place.
And secondly, there
was an argument
in the scientific literature
about the importance
of competition between
species for basic requirements
like food or nest
sites, and that
as a result of this competition,
when two species came together,
they will likely to be
subject to natural selection
and diverge.
And so the reason why we see
differences between species,
let's say here in Massachusetts
in birds, mammals, or software,
whatever it is that they've
undergone a process by which
not only have they been
selected in different directions
for adjustment to their
own particular environment,
but they have in under
some circumstances, been
selected to minimize
competitive interactions
between the entities.
And here on the
Galapagos, we thought
we may see the evidence
for it as a process.
Whereas here in
Massachusetts-- we
didn't have Massachusetts in
mind, but continental regions,
we would see the product of
the process but not the process
itself.
And so it looked very
favorable for that.
And we did not know
that we were going
to be more than about two or
three years to study the birds.
It has taken a long time to
really establish the processes
that both Rosemary and I have
been talking about today.
How did it go from two to three
year study, to a 40 year study?
And what are the challenges
of keeping a study going that
long?
It's very difficult. I'm
sure it's more difficult now
than it was in our day.
And it was bad
enough in those days,
because research money
is available usually,
if you're lucky, in
three year pieces.
And so after three years of
doing a piece of field research
in Galapagos, we had to
demonstrate to our funding
agency, which in those days, was
the National Science and Energy
Research Council of Canada.
We had to demonstrate
that we had
something special discovered
in the first three years
that led naturally to
a problem that we could
solve for the next three years.
Well, fortunately
we had exactly that.
So we got the funding
for the second level.
And we thought that
maybe five or six years
would be as much as we could
possibly persuade a funding
agency to give us money for.
Because there was a
general informal--
that's outside the research
granting agencies--
but an informal idea that we
went down to the Galapagos
to lie on the beaches and
have a really good time.
Well, you see what
Daphne is like.
How many beaches of
sand did you see?
None.
So anyway, we did the
second three year stint.
And that's where the
1977 drought occurred.
We discovered we
thought, that we now
had wonderful opportunities for
continuing further research.
We had previously demonstrated
the heritable nature also
beak size variation.
The natural selection
completed one unit of study,
but then in this kind
of scientific research,
one question always leads
to at least two others.
And we wanted to know
transgenerational effects
better than we could establish
in the first two periods
of funding of three years.
So that led to another
one-- and then I'm
going to stop in a
moment, don't worry.
I would just say that there
came a time when we realized
after quite a number of years,
that hybridization wasn't
a dead end, but
there was actually
genes going from species
A into species B,
and back again from B to A. And
fast forward now to 40 years
later, we're now
in the genomic era.
So we're able to do the
genetic analysis of what
we knew on the
observational level,
all the way back in the early
1970s which is a very, very
satisfying way to spend more
than 40 years of one's life.
I'll just add one
sentence that actually,
none of our findings were ever
put into a research grant ,
because it was
impossible, right?
Yeah, we could never
say, oh next year,
we're going to discover
natural selection.
So the video clips
that Peter showed,
I think we're taking recently.
And it looks like
pretty rough conditions.
What was it like 40 years ago?
Was it any different?
Well, the boats delivering
us to the islands
were very different,
but we were younger.
So we could cope
a bit be better.
But no actually, apart
from what I showed you
that the island had been
converted into something that's
of a small seed
producer, yet the island
really has changed very little.
Wouldn't you say?
From 1973, when we went there.
Apart from the transition
from pre-Nino to Nino,
but even allowing for that,
the drought of 2003 to 2005
was really more severe
than the one in 1977.
So I don't know what the island
looks like now this year,
because this is supposed to be
an El Nino year, although it
hasn't rained very much.
But just recently,
just let's say 2010,
the island would not look
very different from what
it looked like in 1973 in
our first year of study.
In fact, one of the
people who worked
with us in the early
days, Peter Boyle,
went back about 15
years later, and he
didn't see the difference.
It was a subtle difference
that we could detect.
He did not see much in
the way of a difference
between the islands.
The seed supply was
definitely different,
so that required a scientific
study to establish.
So hindsight is always 20/20.
If you were starting again now,
what would you do differently?
Well, when we first started,
we did not take blood samples
because it in the days
before you could actually
analyze any of the blood
samples or microsatellites.
But actually what
we did do, we had
thought about this a little
bit, and we took a little bit
of a small feather.
And we did a feather smear,
and looked at the chromosomes
on some of the birds.
And when we analyzed
that, we found that also
by taking a feather, which
the birds had a black.
And so they had these
little granules in it.
And we couldn't really tell the
difference between the granules
and the microchromosomes.
So it didn't work very well.
But actually, those
slides we kept.
And we were able
later to use the blood
from some of those sides
for the genetic analysis.
But I wish we had really
systematically taken
a small drop of blood from
every single bird, which
we started to do in 1988 was
the first time we started
to do this.
So I'd add to that we would,
if we had the time over again,
do more botanical studies.
The plant that the
finches put pressure upon,
that plant Tribulus.
And it's possibly
selective in that they
may have been cracking open the
easier ones, the smaller ones.
The ones with only two spines
instead of the four spines,
and so on.
And it's possible
that an evolutionary--
but a very subtle
evolutionary change
had taken place over the
years in the Tribulus plants.
A couple of reasons
why I don't think that
is so, one is that
they're perennial.
So this year's crop may be
wiped out by consumption
by the finches, but the plants
are going to be producing.
Most of the plants
are going to be
surviving and producing seeds
and fruits the following year.
So it's not quite the
same as the finches,
but nonetheless,
I think it would
have been a very
interesting study
to do a parallel investigation
of the plant, the seeds that
are exploited by the
finches, at the same time
as doing the study
of the finches.
And maybe also the cactus.
I haven't mentioned
the cactus very much.
So you've been studying these
finches for 40 years now.
And people might think
you know everything
there is to know about
Darwin's finches.
But I'm going to guess that
there are some things that
remain unknown.
What do you think,
what's the next frontier?
Or what would you like to
know about these birds?
Everything.
What would we like to know?
Our science progresses most
of the time incrementally,
with a slightly better
understanding of this
and slightly better
understanding of that.
We would like to go much
further in understanding
the phylogenetic
history of the group.
That's one clear problem area.
Another one is we
would love to be
able to explain to anybody who
asks us how is a beak formed?
And why does that one I have
that size and shape, and what
is this one have a beak of
a different size and shape?
Well, we know some
things about the genes
that are responsible
for the differences
between the individuals,
but only some things.
There's an enormous amount
more work yet to be done.
And many, many more
discoveries to be made.
If people carry on doing
Darwin's finch work well
after we're either under the
ground or in the air somewhere,
they will be working with the
genomic tools of the 2030s
and the 2040s with
still pathways involved
in the development of structures
like beaks and cranium
and the muscle that go with
it, and so on, to peel back
the various pathways
that are responsible
for the adult structures.
So I think there's an enormous
amount to be done there.
And then ecologically,
we've had the good fortune
to have a complete drought
of no rain whatever.
Not even a single
millimeter one year,
and we've had 1.3 meters of rain
in that extraordinary 1983 El
Nino.
Well, that's impressive.
Are they the limits?
I doubt it.
Zero you can't
beat, but 1.3 meters
you can with the next
major, major El Nino of who
knows when that produces
two meters of rain.
And maybe over 10
months or 11 months.
Well, the thing that we would
anticipate most affecting
the finches and for which
we are still in ignorance of
is what would happen
if droughts now
occur not in ones and
two successive years,
but three and four?
What about the possibility
of a five year drought?
Would the finches be wiped out?
Would they be reduced to an
exceedingly small number?
Would we see a major change
taking place that we have not
seen in 40 years?
And what about the arrival of
a new food onto the island that
enables a new ecological
niche or create
a new ecological niche
for a new kind of finch?
And what about the evolutionary
forces producing a finch fitted
to this new ecological niche?
I bet in the long, long, long
term, that could be studied.
And so I would like to know
the answers before I quit.
I would like to know
the genetics underlying
the big bird formation,
which I think is in progress.
And so maybe in
a year or two, we
will actually be able to
find out more about that.
So that means the
beginning of the genetics
of possibly a new species
or new lineage forming.
And the other thing
I'd like to know
is I didn't mention
the song at all.
But the song is
interesting in these birds.
It's one of the few
species of birds
where the song is learned
very early in a very short
sensitive period of time.
Many of the song birds
will learn their song,
and that's about 1/2 the number
of birds, and another 1/2
of birds didn't
learn their song.
And it's very interesting
how song is learned,
and then why do some
species of birds
only learn for a
very short time,
and others were learned
throughout their life.
And this I think, has
a bearing on ourselves.
It has a bearing on
language formation.
And if I had
another longer life,
I think that would
be another thing.
And Darwin's finches
could play a role there.
So with regard to the
big birds, don't you
think what would be
really nice to know
is how genes from one species
and genes from another,
when they come together,
how they interact.
In the case of the
big bird, it looks
as if there's a combination of
genes that made for success.
We don't know that,
but that's the question
that we would like
to be able to answer.
Because it's obviously
not a clear mixing.
Because they have
remained large,
maybe some genes coming in,
and some remaining, and then
other genes being brought.
So I think the whole
genetic architecture
and what is going on
will be fascinating.
Maybe we will get part of
the way, and then all you
younger people
could take it over.
That's actually what I
was about to ask you.
Your work has been an
inspiration to many people
for many years.
There are in the audience
I see, undergraduates
thinking of a career in
evolutionary biology.
There are graduate
students, who knows?
Maybe high school students,
or even younger who
will be inspired today.
What is the message
you would like
them to take from your talk, or
to think about as they develop
their own careers?
Well, to find something
that interests you know
and literally, to follow your
passion or follow your heart.
And don't let yourself
be dissuaded just plug on
and follow it.
And also, the other
thing that I would say
is as you're doing
this, don't be
too blinkered by your
theoretical expectations,
but actually follow
your exceptions.
Because it's been actually
us following our exceptions
that have led to the most
exciting discoveries.
So I would say follow
your passion, and lookout
for the exceptions.
And follows those.
Would you agree?
I agree.
Would you recommend that a
young researcher embark maybe
not on a 40 year study, but
think about a long term study?
Well, a 40 year
study can be improved
upon by a 50 year study.
And they're younger.
We started at 35, why didn't
they start at 25, right?
No, I would emphasize or
echo what Rosemary said.
If there are young people here
who are inspired to any degree
by the work that Jonathan
does, Rosemary or I do,
then there is in enormous
scope for further research
and investigations
into this whole field
of ecological genetical
evolutionarily biology,
out in the field and
in the laboratory.
An enormous amount of scope.
So go for it!
Get the money, though.
