well under the banner of the Big Ideas
among other things we will be talking
about in this discussion who lives who
dies finding clues to understanding how
species function live and survive for
this conversation I’m pleased to
introduce dr. Martin Chalfie and dr.
Beth Shapiro Martin is a professor of
biology at Columbia he was awarded the
2008 Nobel Prize in Chemistry for
developing a way to use the green
fluorescent protein to see and track
molecules in a living organism in real
time and Beth is a National Geographic
emerging Explorer and professor of
biology soon to be at the University of
California at Santa Cruz and she studies
DNA from ancient animals and plants to
discover how evolution happens over time
and territory and how some species
survive and others become extinct you
were looking for things to take DNA
samples of an ancient you’re looking at
extinct species
nothing could probably be more famous
than a dodo and they’re not a lot of
remains left to go and pick through to
say well let me get some of this bone
sample and what do you do you grind it
up you have to and if you’ve got a dodo
skeleton then you have to say do you
mind if I destroy part of your skeleton
I spend a lot of my time asking people
to destroy parts of their collections
yes it’s it’s kind of upsetting more for
them than for me and and the dodo you
found is this the the same dodo that
inspired Lewis Carroll and Allison it is
it’s the dodo from the Oxford University
Museum of Natural History and it’s a
it’s actually quite a fun story this was
during my PhD it was the first bit of
ancient DNA work that I was doing and my
lab I was working with fessor Alan
Cooper who’s now in in Adelaide and he
really wanted to do this work and they
didn’t trust that if they let the dodo
sit somewhere in the museum where he
could get to it he wouldn’t sneak in
late at night and take that sample
without permission so they hid it from
us and we went and we got DNA for
a closely related bird a bird called the
solitaire that lived on a nearby island
to the island that the dodo lived on and
we showed that it was possible we could
get DNA out of it and we could tell what
kind of bird that was and they said
great now you have permission to sample
the dodo and they went to get it for us
and they couldn’t find it and it took
several days of panicked looking to
finally find this famous dodo specimen
and then I felt terrible drilling a hole
into it but we did and it turns out the
dodo is a fat pigeon so it disappeared
but it’s relatives live on many
relatives no it would seem if you’re
trying to determine genetically what
makes a species disappear the dodo
wouldn’t be a good example because it’s
pretty obvious you got a really
overweight bird with weak wings so it
can’t fly this may be a lesson for the
American population given their physique
newspaper
can’t get up and move around much so it
was consumed by introduced species that
just ate it right the dodo laid a single
egg got a nest on the ground and it
wasn’t people eating them there’s lots
of records from the Portuguese and the
Dutch that first came on to Mauritius
Island they didn’t like the way the dodo
tasted it was gross they didn’t want to
eat it but they brought with them cats
and pigs and rats and these animals just
went along the ground and ate the egg
and if you can’t reproduce you can’t
survive I think it took about 50 years
between the first appearance of humans
on Mauritius and the last dodo to die
this is a pretty rapid extinction event
so the bottom line we on the dodo we’ve
learned this was our fault this was our
fault yes it was nothing in the genetics
of it well I don’t know I mean this gets
back to gets back to some of the
questions that I think might link my
work and and your work a little bit more
I mean I know you work at the cellular
level and I’m more of an evolutionary
biologist so we’re kind of coming at
these questions from very different
perspectives but we know a lot about the
genome now of our own genome and about
of other animals and we can look and ask
whether there are specific differences
within populations that might make some
individuals
or inclines to be able to adapt to a
changing environment like a new predator
coming or warming of the atmosphere we
don’t of course have a way of looking at
these proteins of things that are dead
and saying you know does this protein
actually is a difference between this
animal and this one because we can’t we
can’t do that but maybe there’s a way we
can actually work this in here maybe
maybe it’s what we do said I really
examples is that people have been able
to study the rise of or the appearance
of lactose intolerance in people by
studying the genes that are needed for
digesting milk sugar lactose lactase and
seeing that those are when there’s a
population that has this so that one can
start to study these differences that
lead to different changes and of course
as people domesticated animals started
using getting milk from cattle that
changed they had to change their biology
to be able to to cope with this for a
much longer period of time some people
don’t have that they become lactose
intolerant yeah this is actually a
really nice example I think of how all
the technological advances that have
happened in the last couple of decades
are really bringing people from
disparate scientific backgrounds
together to address questions and we’re
really making good progress this lactose
persistence question was one of the
first things that was really discovered
with the human genome project and
looking between populations and they
know we know now what specific genetic
change what one genetic change results
in an alteration of a protein that keeps
us making this enzyme that lets us break
down milk even after we’re weaned if we
have that mutation if you’re lactose
intolerant by the way you are not the
mutant right
we are the mutant but it was nice to see
that we could even pinpoint when that
happened and the correlation between the
timing of the appearance of that
mutation in European populations at
least and cattle domestication is
incredible I mean this really is a
cause-and-effect relationship that we
could only tease apart through this new
technology
and interaction between people with
different expertise and Marty perhaps
you should explain your work just a
little bit so people will understand
what you have done with this green
fluorescent protein because you’ve
essentially been tickling worms your
whole life well for the least the last
35 years
yes I do they laugh when you do that no
and and they don’t complain either
that’s it’s very nice I think actually
what death and I both share it is that
what we do has been profoundly affected
by technology whether it’s DNA
sequencing or in my case just also DNA
sequencing for the genetics that I do
but also this green fluorescent protein
the basic idea of green fluorescent
protein why it people have found it so
useful is because it’s a protein it can
be encoded in DNA you can have a piece
of DNA that will give you the
instructions you can put this in any
organism plants animals bacteria viruses
anything and they and all of their
subsequent progeny will produce it in a
particular cell or whatever and because
it a cell or an organism part of a cell
will make this protein you can see where
it is simply by shining usually blue
light and seeing where the green light
is and once you can start to see things
then all sorts of questions open are
possible to be addressed so for example
I’m interested in nerve cell development
a nerve cell has a cell body it has a
long process that comes out usually and
then it may branch well we can generate
animals I study a very small one
millimeter large long worm we can make a
worm in which only the cells were
interested in have this green
fluorescent protein so when we shining a
light that’s all we see is that cell and
then we can look for variants mutants in
that animal and we can look for mutants
in which the nerve cells don’t grow off
appropriately maybe they will have
they’ll be growing off in the wrong
direction or maybe they’ll have to
processes rather than one or maybe
they’ll branch more or less or maybe
there’ll be more cells or fewer cells
all of these defects allow us to ask
questions about how nerve cells develop
in a way that we can then study this
phenomena not only in the organism we’re
studying but in others as well and the
nicest thing about this is that shining
blue light onto something really doesn’t
hurt it so you can watch things
happening dynamically over time maybe
this is something that is another bridge
between what we do is is that technology
allows us to look at something as a
process as it’s actually happening and
rather than just make inference based on
what you see right now and extrapolate
backwards or or project forward in time
we can actually watch these things we
with ancient DNA the real goal of
ancient DNA is not to recreate a
dinosaur clone a mammoth but to be able
to see how populations respond to
changes in their habitat as it’s
happening so we do a lot of work in the
Arctic where we’re looking at
populations of mammoths and horse and
and bison as they go through the peak of
the last ice age and come out the other
side and we ask how do these dramatic
changes in temperature and climate and
habitat availability change their
population but with the ancient DNA we
can watch it as it happens so we can see
when their population is small when it
grows to be bigger when it shrinks again
and ask what’s causing that and it’s a
real it’s a neat new insight here’s the
bottom line we know about life and death
the moment we’re born we’re starting to
die so it’s going to come at some point
is it is there a way of delaying the
inevitable with with this kind of study
if we can see all right we can slow down
a process that’s going to take place in
Cassell’s die cells die but cells also
die as a normal part of development
right the fact that we have fingers is
because as young embryos there was
webbing there and that died so that we
actually have fingers and not flippers
so and about 50% of our nerve cells that
are made
actually died because probably because
they don’t wire up appropriately so cell
death is a normal part of development
but you asked you know is there a way of
keeping things like I don’t think we
really age because cells are dying in us
that’s that dot I think it is not
correct and in fact this worm has been
the subject of a lot of studies to find
mutations that allow the animal to live
longer I was just going to there’s a
group at Stanford who is trying to look
into the genetics of longevity and
humans do you work at all on anything
that has to do with with humans or you
focused on the worm well because I feel
that there’s so much to discover about
basic biology and because evolution
works we know that if we study things in
this warm where we have really wonderful
tools and great information that there’s
going to be some insights that are going
to be developed from this work that we
can do much faster so for example I have
a colleague a couple of years ago got in
touch with me he has a lab in Germany
and he’s a kidney surgeon and he’s
studying a protein that is defective in
some people with kidney disease it turns
out to be very similar to a protein that
we work on that is needed for the sense
of touch and norms and together we did a
study that showed that both of these
proteins had a lot of similar properties
one of one one of which was that it
bound cholesterol and so we having the
insights really from a model organism it
can be used to give direction to studies
it doesn’t give the answers but it gives
directions to the studies and now the
pressure is really on you and your
research path and all geneticists
because we have been led to believe and
that’s from the layman point of view
that if we could string out our and map
our DNA sequences we could look at each
gene and say oh there’s where we’re
wrong we can go in and correct that and
it will improve lives take care of
illnesses disease diseases and
provide longer life and the pressures on
me to do that yes you’re a very
frightening man and you’re doing this by
studying polar bears though that we we
have learned Lots since the first
complete human genome was published but
there is still a long way to go and all
those things are things that were said
by people when they were trying to
justify funding the initial human genome
project this is a problem and this is so
this is a problem in science and it’s
something that we’ve been talking about
a bit as well as this need to justify
yourself constantly to do basic research
when some of the most fundamental
insights in science come from basic
research not from translational research
that goes directly into something that’s
medically relevant to extend human life
or to make you feel better in the
morning when you get up since you’re
looking at ancient species and what may
have happened to them
woolly mammoth you can see what lesson
can we take of what went wrong with them
for us today and what did go wrong by
the way well the research so far
suggests that all of these animals were
really the dynamics of their populations
were driven in to a large extent by the
climate turns out from the research that
we’ve done so far that these guys did
great
when it was cold and actually it was
warming after the last ice age that
stressed them out and because the
populations all started to decline
around Oh twenty or fifteen thousand
years ago we like to look at it and say
that’s great because we as humans
weren’t even in North America until
fourteen thousand years ago or maybe
more recent than that so it’s totally
not our fault and then we can feel
better about ourselves because of them
but there’s a problem with that and that
is that the Pleistocene the last two
million years was a big oscillation
between ice ages and warm interglacial
periods like we’re in today and there
were many of these and these same
animals survived through all of these
oscillations when it got warm they
survived I found a place to live where
there kind of
habitats that they needed was there a
refuge or refugia if you’d like to call
it them so the only difference then if
we look at this last oscillation and the
many previous places seen oscillations
was that the last time it got warm
everything went extinct and in nine of
the previous times did anything go
extinct and so you have to ask what is
the difference there and the difference
is we were here and so yes they did
start to decline when it got warmer but
they did that every other time it got
warmer just we came in at the very wrong
time when these animals were on the
brink of on the on the edge of their
survival when species don’t make it and
and they go through an evolutionary
period which other species from that
period do make it it’s at about the
speed that they’re able to adapt and
change is that what you’re seeing in
your research how fast mutations can
occur genetically to keep up with the
external impact on them well I’m not
sure about mutations and maybe Marty can
talk a little bit more about this but I
think the part of the problem with
climate change today compared to the
huge oscillations in in global
temperature that have happened
throughout the last two million years is
that the rates of climate change right
now is a lot faster than it has been
before and you don’t mutations might not
need to arise to have these animals
adapt to places but the vegetation needs
an opportunity to be able to expand to
move into different areas as the
coastline rises the coastal vegetation
should be able to should happen so
slowly that that coastal vegetation can
move inland and you still have these
coastal vegetation zones so that all
those species that require that can
survive but if the sea level rises so
quickly that there’s no time for that
movement or because we’ve built
high-rise hotels along all of the coasts
and it can’t move inland that’s when we
lose that ecosystem and that’s the
threat to biodiversity today alright
let’s get to the big question and it’s
the question that got you started raised
by Michael Crichton if something does
disappear a species and we can get its
DNA can we make a new one not yet we
want a t-rex and we want to do
those are two tough ones actually t-rex
probably never because they’re very old
dinosaurs went extinct about 65 million
years ago the oldest DNA that we know
that we have are some bacteria that may
or may not have been alive at low levels
so we don’t know if it really counts as
ancient DNA that are seven hundred
thousand years old we have extracted DNA
from bones from bison and mammoths that
we think are around 120 180 thousand
years old but that’s it all right
didn’t the next big question is if we’ve
got an animal today like the polar bear
that is threatened can we do all the
sampling of the cells since you’re
writing down the wiring of the nervous
system in a worm if we had enough time
and enough research could we write down
the wiring correctly on the polar bear
we got the genetics to rebuild us in you
polar bear from scratch I think it’s the
same question it’s it’s really the same
thing you did but there are all these
things happen now we know what we have
as best as it is we can get a DNA
sequence right we we have this we’ve
known for about not really 10 years but
about seven or so years a pretty good
idea of the human genome sequence but
when you go and you look at that
sequence there are ways of saying oh
that part is one gene this part is
another gene this part and so on and so
you can sort of pick out where the genes
are at least the genes you’re pretty
sure about but most of these right now
if you look up what they make what is
the protein that is encoded the answer
is it’s a protein of unknown function we
don’t know what most of the proteins
that are encoded in the human genome do
we don’t know how these proteins
interact so the idea that all we have to
do is find a
an appropriate recipient egg and dump
this DNA in there’s lots more that
really needs to be worked out and to
study so there’s much much more for us
to learn and to understand it’s not a
simple we have this now we can do this
and as we get more technologically
advanced in science we see all these
huge collaborations between people who
have very different types of expertise
coming together and this is how we’re
making the bigger advances that’s what
we said in the beginning you’re building
on the work and it’s gone for having
something like DNA sequencing techniques
which are just exploding the way we’re
looking at life or having GFP that
allows us to follow phenomena has
changed the way people do their studies
they’re able to ask questions they’ve
never been able to ask before we know
for example inside of us that we have
probably more cells that are bacterial
than human and we’re just now being able
to sequence all these different bacteria
trying to understand what they’re doing
as part of this super organism that is
ourselves before the advent of the DNA
sequencing there was really no way of
looking at that or looking as Beth does
at a much larger thing so we’re at a
very exciting time and technology has
helped us ask different questions do you
think everybody of every generation has
said that though do you think everybody
I’m sure they’re convinced because we
keep developing new ways of looking and
we keep learning more things I think
that’s wonderful and we wouldn’t be here
if we weren’t excited about it
Oh
among other things we will be talking
about in this discussion who lives who
dies finding clues to understanding how
species function live and survive for
this conversation I’m pleased to
introduce dr. Martin Chalfie and dr.
Beth Shapiro Martin is a professor of
biology at Columbia he was awarded the
2008 Nobel Prize in Chemistry for
developing a way to use the green
fluorescent protein to see and track
molecules in a living organism in real
time and Beth is a National Geographic
emerging Explorer and professor of
biology soon to be at the University of
California at Santa Cruz and she studies
DNA from ancient animals and plants to
discover how evolution happens over time
and territory and how some species
survive and others become extinct you
were looking for things to take DNA
samples of an ancient you’re looking at
extinct species
nothing could probably be more famous
than a dodo and they’re not a lot of
remains left to go and pick through to
say well let me get some of this bone
sample and what do you do you grind it
up you have to and if you’ve got a dodo
skeleton then you have to say do you
mind if I destroy part of your skeleton
I spend a lot of my time asking people
to destroy parts of their collections
yes it’s it’s kind of upsetting more for
them than for me and and the dodo you
found is this the the same dodo that
inspired Lewis Carroll and Allison it is
it’s the dodo from the Oxford University
Museum of Natural History and it’s a
it’s actually quite a fun story this was
during my PhD it was the first bit of
ancient DNA work that I was doing and my
lab I was working with fessor Alan
Cooper who’s now in in Adelaide and he
really wanted to do this work and they
didn’t trust that if they let the dodo
sit somewhere in the museum where he
could get to it he wouldn’t sneak in
late at night and take that sample
without permission so they hid it from
us and we went and we got DNA for
a closely related bird a bird called the
solitaire that lived on a nearby island
to the island that the dodo lived on and
we showed that it was possible we could
get DNA out of it and we could tell what
kind of bird that was and they said
great now you have permission to sample
the dodo and they went to get it for us
and they couldn’t find it and it took
several days of panicked looking to
finally find this famous dodo specimen
and then I felt terrible drilling a hole
into it but we did and it turns out the
dodo is a fat pigeon so it disappeared
but it’s relatives live on many
relatives no it would seem if you’re
trying to determine genetically what
makes a species disappear the dodo
wouldn’t be a good example because it’s
pretty obvious you got a really
overweight bird with weak wings so it
can’t fly this may be a lesson for the
American population given their physique
newspaper
can’t get up and move around much so it
was consumed by introduced species that
just ate it right the dodo laid a single
egg got a nest on the ground and it
wasn’t people eating them there’s lots
of records from the Portuguese and the
Dutch that first came on to Mauritius
Island they didn’t like the way the dodo
tasted it was gross they didn’t want to
eat it but they brought with them cats
and pigs and rats and these animals just
went along the ground and ate the egg
and if you can’t reproduce you can’t
survive I think it took about 50 years
between the first appearance of humans
on Mauritius and the last dodo to die
this is a pretty rapid extinction event
so the bottom line we on the dodo we’ve
learned this was our fault this was our
fault yes it was nothing in the genetics
of it well I don’t know I mean this gets
back to gets back to some of the
questions that I think might link my
work and and your work a little bit more
I mean I know you work at the cellular
level and I’m more of an evolutionary
biologist so we’re kind of coming at
these questions from very different
perspectives but we know a lot about the
genome now of our own genome and about
of other animals and we can look and ask
whether there are specific differences
within populations that might make some
individuals
or inclines to be able to adapt to a
changing environment like a new predator
coming or warming of the atmosphere we
don’t of course have a way of looking at
these proteins of things that are dead
and saying you know does this protein
actually is a difference between this
animal and this one because we can’t we
can’t do that but maybe there’s a way we
can actually work this in here maybe
maybe it’s what we do said I really
examples is that people have been able
to study the rise of or the appearance
of lactose intolerance in people by
studying the genes that are needed for
digesting milk sugar lactose lactase and
seeing that those are when there’s a
population that has this so that one can
start to study these differences that
lead to different changes and of course
as people domesticated animals started
using getting milk from cattle that
changed they had to change their biology
to be able to to cope with this for a
much longer period of time some people
don’t have that they become lactose
intolerant yeah this is actually a
really nice example I think of how all
the technological advances that have
happened in the last couple of decades
are really bringing people from
disparate scientific backgrounds
together to address questions and we’re
really making good progress this lactose
persistence question was one of the
first things that was really discovered
with the human genome project and
looking between populations and they
know we know now what specific genetic
change what one genetic change results
in an alteration of a protein that keeps
us making this enzyme that lets us break
down milk even after we’re weaned if we
have that mutation if you’re lactose
intolerant by the way you are not the
mutant right
we are the mutant but it was nice to see
that we could even pinpoint when that
happened and the correlation between the
timing of the appearance of that
mutation in European populations at
least and cattle domestication is
incredible I mean this really is a
cause-and-effect relationship that we
could only tease apart through this new
technology
and interaction between people with
different expertise and Marty perhaps
you should explain your work just a
little bit so people will understand
what you have done with this green
fluorescent protein because you’ve
essentially been tickling worms your
whole life well for the least the last
35 years
yes I do they laugh when you do that no
and and they don’t complain either
that’s it’s very nice I think actually
what death and I both share it is that
what we do has been profoundly affected
by technology whether it’s DNA
sequencing or in my case just also DNA
sequencing for the genetics that I do
but also this green fluorescent protein
the basic idea of green fluorescent
protein why it people have found it so
useful is because it’s a protein it can
be encoded in DNA you can have a piece
of DNA that will give you the
instructions you can put this in any
organism plants animals bacteria viruses
anything and they and all of their
subsequent progeny will produce it in a
particular cell or whatever and because
it a cell or an organism part of a cell
will make this protein you can see where
it is simply by shining usually blue
light and seeing where the green light
is and once you can start to see things
then all sorts of questions open are
possible to be addressed so for example
I’m interested in nerve cell development
a nerve cell has a cell body it has a
long process that comes out usually and
then it may branch well we can generate
animals I study a very small one
millimeter large long worm we can make a
worm in which only the cells were
interested in have this green
fluorescent protein so when we shining a
light that’s all we see is that cell and
then we can look for variants mutants in
that animal and we can look for mutants
in which the nerve cells don’t grow off
appropriately maybe they will have
they’ll be growing off in the wrong
direction or maybe they’ll have to
processes rather than one or maybe
they’ll branch more or less or maybe
there’ll be more cells or fewer cells
all of these defects allow us to ask
questions about how nerve cells develop
in a way that we can then study this
phenomena not only in the organism we’re
studying but in others as well and the
nicest thing about this is that shining
blue light onto something really doesn’t
hurt it so you can watch things
happening dynamically over time maybe
this is something that is another bridge
between what we do is is that technology
allows us to look at something as a
process as it’s actually happening and
rather than just make inference based on
what you see right now and extrapolate
backwards or or project forward in time
we can actually watch these things we
with ancient DNA the real goal of
ancient DNA is not to recreate a
dinosaur clone a mammoth but to be able
to see how populations respond to
changes in their habitat as it’s
happening so we do a lot of work in the
Arctic where we’re looking at
populations of mammoths and horse and
and bison as they go through the peak of
the last ice age and come out the other
side and we ask how do these dramatic
changes in temperature and climate and
habitat availability change their
population but with the ancient DNA we
can watch it as it happens so we can see
when their population is small when it
grows to be bigger when it shrinks again
and ask what’s causing that and it’s a
real it’s a neat new insight here’s the
bottom line we know about life and death
the moment we’re born we’re starting to
die so it’s going to come at some point
is it is there a way of delaying the
inevitable with with this kind of study
if we can see all right we can slow down
a process that’s going to take place in
Cassell’s die cells die but cells also
die as a normal part of development
right the fact that we have fingers is
because as young embryos there was
webbing there and that died so that we
actually have fingers and not flippers
so and about 50% of our nerve cells that
are made
actually died because probably because
they don’t wire up appropriately so cell
death is a normal part of development
but you asked you know is there a way of
keeping things like I don’t think we
really age because cells are dying in us
that’s that dot I think it is not
correct and in fact this worm has been
the subject of a lot of studies to find
mutations that allow the animal to live
longer I was just going to there’s a
group at Stanford who is trying to look
into the genetics of longevity and
humans do you work at all on anything
that has to do with with humans or you
focused on the worm well because I feel
that there’s so much to discover about
basic biology and because evolution
works we know that if we study things in
this warm where we have really wonderful
tools and great information that there’s
going to be some insights that are going
to be developed from this work that we
can do much faster so for example I have
a colleague a couple of years ago got in
touch with me he has a lab in Germany
and he’s a kidney surgeon and he’s
studying a protein that is defective in
some people with kidney disease it turns
out to be very similar to a protein that
we work on that is needed for the sense
of touch and norms and together we did a
study that showed that both of these
proteins had a lot of similar properties
one of one one of which was that it
bound cholesterol and so we having the
insights really from a model organism it
can be used to give direction to studies
it doesn’t give the answers but it gives
directions to the studies and now the
pressure is really on you and your
research path and all geneticists
because we have been led to believe and
that’s from the layman point of view
that if we could string out our and map
our DNA sequences we could look at each
gene and say oh there’s where we’re
wrong we can go in and correct that and
it will improve lives take care of
illnesses disease diseases and
provide longer life and the pressures on
me to do that yes you’re a very
frightening man and you’re doing this by
studying polar bears though that we we
have learned Lots since the first
complete human genome was published but
there is still a long way to go and all
those things are things that were said
by people when they were trying to
justify funding the initial human genome
project this is a problem and this is so
this is a problem in science and it’s
something that we’ve been talking about
a bit as well as this need to justify
yourself constantly to do basic research
when some of the most fundamental
insights in science come from basic
research not from translational research
that goes directly into something that’s
medically relevant to extend human life
or to make you feel better in the
morning when you get up since you’re
looking at ancient species and what may
have happened to them
woolly mammoth you can see what lesson
can we take of what went wrong with them
for us today and what did go wrong by
the way well the research so far
suggests that all of these animals were
really the dynamics of their populations
were driven in to a large extent by the
climate turns out from the research that
we’ve done so far that these guys did
great
when it was cold and actually it was
warming after the last ice age that
stressed them out and because the
populations all started to decline
around Oh twenty or fifteen thousand
years ago we like to look at it and say
that’s great because we as humans
weren’t even in North America until
fourteen thousand years ago or maybe
more recent than that so it’s totally
not our fault and then we can feel
better about ourselves because of them
but there’s a problem with that and that
is that the Pleistocene the last two
million years was a big oscillation
between ice ages and warm interglacial
periods like we’re in today and there
were many of these and these same
animals survived through all of these
oscillations when it got warm they
survived I found a place to live where
there kind of
habitats that they needed was there a
refuge or refugia if you’d like to call
it them so the only difference then if
we look at this last oscillation and the
many previous places seen oscillations
was that the last time it got warm
everything went extinct and in nine of
the previous times did anything go
extinct and so you have to ask what is
the difference there and the difference
is we were here and so yes they did
start to decline when it got warmer but
they did that every other time it got
warmer just we came in at the very wrong
time when these animals were on the
brink of on the on the edge of their
survival when species don’t make it and
and they go through an evolutionary
period which other species from that
period do make it it’s at about the
speed that they’re able to adapt and
change is that what you’re seeing in
your research how fast mutations can
occur genetically to keep up with the
external impact on them well I’m not
sure about mutations and maybe Marty can
talk a little bit more about this but I
think the part of the problem with
climate change today compared to the
huge oscillations in in global
temperature that have happened
throughout the last two million years is
that the rates of climate change right
now is a lot faster than it has been
before and you don’t mutations might not
need to arise to have these animals
adapt to places but the vegetation needs
an opportunity to be able to expand to
move into different areas as the
coastline rises the coastal vegetation
should be able to should happen so
slowly that that coastal vegetation can
move inland and you still have these
coastal vegetation zones so that all
those species that require that can
survive but if the sea level rises so
quickly that there’s no time for that
movement or because we’ve built
high-rise hotels along all of the coasts
and it can’t move inland that’s when we
lose that ecosystem and that’s the
threat to biodiversity today alright
let’s get to the big question and it’s
the question that got you started raised
by Michael Crichton if something does
disappear a species and we can get its
DNA can we make a new one not yet we
want a t-rex and we want to do
those are two tough ones actually t-rex
probably never because they’re very old
dinosaurs went extinct about 65 million
years ago the oldest DNA that we know
that we have are some bacteria that may
or may not have been alive at low levels
so we don’t know if it really counts as
ancient DNA that are seven hundred
thousand years old we have extracted DNA
from bones from bison and mammoths that
we think are around 120 180 thousand
years old but that’s it all right
didn’t the next big question is if we’ve
got an animal today like the polar bear
that is threatened can we do all the
sampling of the cells since you’re
writing down the wiring of the nervous
system in a worm if we had enough time
and enough research could we write down
the wiring correctly on the polar bear
we got the genetics to rebuild us in you
polar bear from scratch I think it’s the
same question it’s it’s really the same
thing you did but there are all these
things happen now we know what we have
as best as it is we can get a DNA
sequence right we we have this we’ve
known for about not really 10 years but
about seven or so years a pretty good
idea of the human genome sequence but
when you go and you look at that
sequence there are ways of saying oh
that part is one gene this part is
another gene this part and so on and so
you can sort of pick out where the genes
are at least the genes you’re pretty
sure about but most of these right now
if you look up what they make what is
the protein that is encoded the answer
is it’s a protein of unknown function we
don’t know what most of the proteins
that are encoded in the human genome do
we don’t know how these proteins
interact so the idea that all we have to
do is find a
an appropriate recipient egg and dump
this DNA in there’s lots more that
really needs to be worked out and to
study so there’s much much more for us
to learn and to understand it’s not a
simple we have this now we can do this
and as we get more technologically
advanced in science we see all these
huge collaborations between people who
have very different types of expertise
coming together and this is how we’re
making the bigger advances that’s what
we said in the beginning you’re building
on the work and it’s gone for having
something like DNA sequencing techniques
which are just exploding the way we’re
looking at life or having GFP that
allows us to follow phenomena has
changed the way people do their studies
they’re able to ask questions they’ve
never been able to ask before we know
for example inside of us that we have
probably more cells that are bacterial
than human and we’re just now being able
to sequence all these different bacteria
trying to understand what they’re doing
as part of this super organism that is
ourselves before the advent of the DNA
sequencing there was really no way of
looking at that or looking as Beth does
at a much larger thing so we’re at a
very exciting time and technology has
helped us ask different questions do you
think everybody of every generation has
said that though do you think everybody
I’m sure they’re convinced because we
keep developing new ways of looking and
we keep learning more things I think
that’s wonderful and we wouldn’t be here
if we weren’t excited about it
Oh
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