my subject is the future of life on earth this is a very large and complex
earth this is a very large and complex
earth this is a very large and complex topic it’s the subject of futurology in
topic it’s the subject of futurology in
topic it’s the subject of futurology in fact I am a paleontologist I study
fact I am a paleontologist I study
fact I am a paleontologist I study dinosaurs and you might wonder why a
dinosaurs and you might wonder why a
dinosaurs and you might wonder why a paleontologist would have something to
paleontologist would have something to
paleontologist would have something to say about the future however there are
say about the future however there are
say about the future however there are some shared aspects which I will talk
some shared aspects which I will talk
some shared aspects which I will talk about and this can provide some evidence
about and this can provide some evidence
about and this can provide some evidence to help us in making decisions
to help us in making decisions
to help us in making decisions I’m paleontologist as I say I decided on
I’m paleontologist as I say I decided on
I’m paleontologist as I say I decided on this career when I was 7 years old
this career when I was 7 years old
this career when I was 7 years old I loved dinosaurs at the age of 7 and I
I loved dinosaurs at the age of 7 and I
I loved dinosaurs at the age of 7 and I think these days young people still do I
think these days young people still do I
think these days young people still do I am and I haven’t changed my views since
am and I haven’t changed my views since
am and I haven’t changed my views since I love the job teaching students going
I love the job teaching students going
I love the job teaching students going to exotic parts of the world to dig up
to exotic parts of the world to dig up
to exotic parts of the world to dig up dinosaurs finding new facts about the
dinosaurs finding new facts about the
dinosaurs finding new facts about the history of life however this kind of
history of life however this kind of
history of life however this kind of subject studying the past like studying
subject studying the past like studying
subject studying the past like studying the future could be said by some not to
the future could be said by some not to
the future could be said by some not to be truly scientific and I want to
be truly scientific and I want to
be truly scientific and I want to explore that a little bit first how do
explore that a little bit first how do
explore that a little bit first how do we do this
we do this
we do this before we get to the point of beginning
before we get to the point of beginning
before we get to the point of beginning to establish some facts and figures
to establish some facts and figures
to establish some facts and figures about life and current threats so and
about life and current threats so and
about life and current threats so and this has been criticized by other
this has been criticized by other
this has been criticized by other scientists for example a hundred years
scientists for example a hundred years
scientists for example a hundred years ago Sir Ernest Rutherford a very famous
ago Sir Ernest Rutherford a very famous
ago Sir Ernest Rutherford a very famous physicist nobel prize winner said all of
physicist nobel prize winner said all of
physicist nobel prize winner said all of science is physics and the rest is stamp
science is physics and the rest is stamp
science is physics and the rest is stamp collecting by which he meant that if it
collecting by which he meant that if it
collecting by which he meant that if it you cannot make it into mathematics or
you cannot make it into mathematics or
you cannot make it into mathematics or physics it doesn’t count that excludes
physics it doesn’t count that excludes
physics it doesn’t count that excludes there in the Natural Sciences Medicine
there in the Natural Sciences Medicine
there in the Natural Sciences Medicine and a lot of other areas and I think at
and a lot of other areas and I think at
and a lot of other areas and I think at the far end of the spectrum would be my
the far end of the spectrum would be my
the far end of the spectrum would be my subject paleontology I’d like to give
subject paleontology I’d like to give
subject paleontology I’d like to give you an example though to show you how we
you an example though to show you how we
you an example though to show you how we apply scientific methods to achieve a
apply scientific methods to achieve a
apply scientific methods to achieve a certain level of understanding
certain level of understanding
certain level of understanding uncertainty and this has been something
uncertainty and this has been something
uncertainty and this has been something that has been developing during my
that has been developing during my
that has been developing during my career so that when I started a lot of
career so that when I started a lot of
career so that when I started a lot of what we did would be called speculation
what we did would be called speculation
what we did would be called speculation or guesswork
or guesswork
or guesswork whereas now a lot of what we do can be
whereas now a lot of what we do can be
whereas now a lot of what we do can be tested and we can be called scientific
tested and we can be called scientific
tested and we can be called scientific the example I’m going to take is that
the example I’m going to take is that
the example I’m going to take is that question I asked when I was 7 could
question I asked when I was 7 could
question I asked when I was 7 could t-rex bite a car
t-rex bite a car
t-rex bite a car are in half this is a question about the
are in half this is a question about the
are in half this is a question about the most famous dinosaur Tyrannosaurus Rex
most famous dinosaur Tyrannosaurus Rex
most famous dinosaur Tyrannosaurus Rex which was huge five tons in weight
which was huge five tons in weight
which was huge five tons in weight enormous jaws and teeth could it bite a
enormous jaws and teeth could it bite a
enormous jaws and teeth could it bite a car in half
car in half
car in half well there were no cars in the
well there were no cars in the
well there were no cars in the Cretaceous but let’s forget that for the
Cretaceous but let’s forget that for the
Cretaceous but let’s forget that for the moment when I started you could only
moment when I started you could only
moment when I started you could only answer that question by guesswork or you
answer that question by guesswork or you
answer that question by guesswork or you could make some very simple models of
could make some very simple models of
could make some very simple models of the skull like levers and try to
the skull like levers and try to
the skull like levers and try to calculate things if you were going to
calculate things if you were going to
calculate things if you were going to make a realistic model that had all the
make a realistic model that had all the
make a realistic model that had all the properties of the original bone and
properties of the original bone and
properties of the original bone and flesh of the dinosaur you could not do
flesh of the dinosaur you could not do
flesh of the dinosaur you could not do it but now with the power of computing
it but now with the power of computing
it but now with the power of computing we can do this kind of thing
we can do this kind of thing
we can do this kind of thing so the way you calculate the bite force
so the way you calculate the bite force
so the way you calculate the bite force of t-rex and the way people have done it
of t-rex and the way people have done it
of t-rex and the way people have done it is they scan a skull and make a
is they scan a skull and make a
is they scan a skull and make a three-dimensional digital model inside
three-dimensional digital model inside
three-dimensional digital model inside the computer you then divide that model
the computer you then divide that model
the computer you then divide that model into a mesh or into a framework of
into a mesh or into a framework of
into a mesh or into a framework of elements or small components and each of
elements or small components and each of
elements or small components and each of these elements can be given and physical
these elements can be given and physical
these elements can be given and physical properties so that we know the physical
properties so that we know the physical
properties so that we know the physical properties of bone of living animals
properties of bone of living animals
properties of bone of living animals these are material properties like how
these are material properties like how
these are material properties like how far can you twist the bone before it
far can you twist the bone before it
far can you twist the bone before it breaks
breaks
breaks how much compression can that bone take
how much compression can that bone take
how much compression can that bone take and so all of those properties are
and so all of those properties are
and so all of those properties are mapped into the skull and then you apply
mapped into the skull and then you apply
mapped into the skull and then you apply imaginary forces and increase those
imaginary forces and increase those
imaginary forces and increase those pressures until the thing breaks and so
pressures until the thing breaks and so
pressures until the thing breaks and so the bite force of t-rex is huge let me
the bite force of t-rex is huge let me
the bite force of t-rex is huge let me lead you to the figure our bite force is
lead you to the figure our bite force is
lead you to the figure our bite force is about 800 Newtons at most the biggest
about 800 Newtons at most the biggest
about 800 Newtons at most the biggest bite force of any living animal is the
bite force of any living animal is the
bite force of any living animal is the great white shark and that is about
great white shark and that is about
great white shark and that is about 5,000 Newtons
5,000 Newtons
5,000 Newtons t-rex 50,000 Newtons ten times and
t-rex 50,000 Newtons ten times and
t-rex 50,000 Newtons ten times and that’s equivalent to five tons of weight
that’s equivalent to five tons of weight
that’s equivalent to five tons of weight acting so it could bite a car in half
acting so it could bite a car in half
acting so it could bite a car in half why do we believe this method because
why do we believe this method because
why do we believe this method because this method is a standard in design and
this method is a standard in design and
this method is a standard in design and architecture finite element analysis is
architecture finite element analysis is
architecture finite element analysis is used for designing buildings like this
used for designing buildings like this
used for designing buildings like this one you don’t simply build it and hope
one you don’t simply build it and hope
one you don’t simply build it and hope it doesn’t fall down the thing is
it doesn’t fall down the thing is
it doesn’t fall down the thing is designed in a computer it is stress
designed in a computer it is stress
designed in a computer it is stress tested using
tested using
tested using actly this program we apply to the
actly this program we apply to the
actly this program we apply to the dinosaur I think we can believe it
dinosaur I think we can believe it
dinosaur I think we can believe it but let’s move on so that was just a
but let’s move on so that was just a
but let’s move on so that was just a brief word about how you can actually
brief word about how you can actually
brief word about how you can actually apply science I would argue two
apply science I would argue two
apply science I would argue two questions that are not happening at our
questions that are not happening at our
questions that are not happening at our time in the past or maybe in the future
time in the past or maybe in the future
time in the past or maybe in the future and in paleontology we don’t just find
and in paleontology we don’t just find
and in paleontology we don’t just find fossils we also care about evolution and
fossils we also care about evolution and
fossils we also care about evolution and diversification how groups have become
diversification how groups have become
diversification how groups have become diverse how groups go extinct and at the
diverse how groups go extinct and at the
diverse how groups go extinct and at the moment we are crucially concerned about
moment we are crucially concerned about
moment we are crucially concerned about extinction so let’s have a look at that
extinction so let’s have a look at that
extinction so let’s have a look at that let’s explore that what are the current
let’s explore that what are the current
let’s explore that what are the current views and these views are expressed not
views and these views are expressed not
views and these views are expressed not by scientists but also the very
by scientists but also the very
by scientists but also the very important politicians so some of you may
important politicians so some of you may
important politicians so some of you may recall a number of years ago Al Gore who
recall a number of years ago Al Gore who
recall a number of years ago Al Gore who was then vice president of the United
was then vice president of the United
was then vice president of the United States he quoted a figure of 100 species
States he quoted a figure of 100 species
States he quoted a figure of 100 species are going extinct every day so this is a
are going extinct every day so this is a
are going extinct every day so this is a very high rate of extinction 100 per day
very high rate of extinction 100 per day
very high rate of extinction 100 per day which is equivalent to 40,000 per year
which is equivalent to 40,000 per year
which is equivalent to 40,000 per year at the other end other politicians
at the other end other politicians
at the other end other politicians perhaps in president Trump’s camp would
perhaps in president Trump’s camp would
perhaps in president Trump’s camp would say don’t worry about it extinction
say don’t worry about it extinction
say don’t worry about it extinction happens look at the dinosaurs we’ve got
happens look at the dinosaurs we’ve got
happens look at the dinosaurs we’ve got nothing to do so how do you connect
nothing to do so how do you connect
nothing to do so how do you connect between these two positions because of
between these two positions because of
between these two positions because of course we have to think about these
course we have to think about these
course we have to think about these points the first approach that we use is
points the first approach that we use is
points the first approach that we use is to look at history we have recent
to look at history we have recent
to look at history we have recent history recorded of extinction so many
history recorded of extinction so many
history recorded of extinction so many of you will be familiar with the extinct
of you will be familiar with the extinct
of you will be familiar with the extinct bird called the dodo this lived on the
bird called the dodo this lived on the
bird called the dodo this lived on the island of Mauritius in the Indian Ocean
island of Mauritius in the Indian Ocean
island of Mauritius in the Indian Ocean the dodo was kind of fat flightless bird
the dodo was kind of fat flightless bird
the dodo was kind of fat flightless bird related to pigeons and a very famous
related to pigeons and a very famous
related to pigeons and a very famous image of the dodo was in the famous
image of the dodo was in the famous
image of the dodo was in the famous children’s book Alice in Wonderland
children’s book Alice in Wonderland
children’s book Alice in Wonderland where the dodo who is a wise old
where the dodo who is a wise old
where the dodo who is a wise old gentleman with a walking stick
gentleman with a walking stick
gentleman with a walking stick organisers Alice and all the animals and
organisers Alice and all the animals and
organisers Alice and all the animals and says to them we will have a caucus-race
says to them we will have a caucus-race
says to them we will have a caucus-race and a caucus-race is one way people
and a caucus-race is one way people
and a caucus-race is one way people start when they like and they finish
start when they like and they finish
start when they like and they finish when they like and everybody gets
when they like and everybody gets
when they like and everybody gets surprised so that was very nice but
surprised so that was very nice but
surprised so that was very nice but unfortunately the dodo in real life
unfortunately the dodo in real life
unfortunately the dodo in real life didn’t get a prize because some of you
didn’t get a prize because some of you
didn’t get a prize because some of you may know that the first record
may know that the first record
may know that the first record of Dodos was in 1598 when semen reported
of Dodos was in 1598 when semen reported
of Dodos was in 1598 when semen reported they had seen this bird they could go on
they had seen this bird they could go on
they had seen this bird they could go on the island and catch it very easily and
the island and catch it very easily and
the island and catch it very easily and eat it and within sixty years it was
eat it and within sixty years it was
eat it and within sixty years it was extinct
extinct
extinct another example of recorded extinction
another example of recorded extinction
another example of recorded extinction is the Great Auk this was a large bird
is the Great Auk this was a large bird
is the Great Auk this was a large bird that lived in the North Atlantic and the
that lived in the North Atlantic and the
that lived in the North Atlantic and the Great Auk went extinct in 1844 how do we
Great Auk went extinct in 1844 how do we
Great Auk went extinct in 1844 how do we know that because collectors sent by a
know that because collectors sent by a
know that because collectors sent by a museum shot the last example they were
museum shot the last example they were
museum shot the last example they were concerned that their museum did not have
concerned that their museum did not have
concerned that their museum did not have a stuffed specimen of this bird they
a stuffed specimen of this bird they
a stuffed specimen of this bird they heard it was going extinct so they
heard it was going extinct so they
heard it was going extinct so they thought we’d better get one before it
thought we’d better get one before it
thought we’d better get one before it dies out so these are two examples of
dies out so these are two examples of
dies out so these are two examples of data about extinction and indeed through
data about extinction and indeed through
data about extinction and indeed through the last five hundred years mankind has
the last five hundred years mankind has
the last five hundred years mankind has killed many species which are recorded
killed many species which are recorded
killed many species which are recorded like that and this is the basis of the
like that and this is the basis of the
like that and this is the basis of the figure that Al Gore gave let me explain
figure that Al Gore gave let me explain
figure that Al Gore gave let me explain it he gave that figure of 100 species
it he gave that figure of 100 species
it he gave that figure of 100 species per day going extinct this was based on
per day going extinct this was based on
per day going extinct this was based on the bird data but we know something like
the bird data but we know something like
the bird data but we know something like a hundred or two or three hundred
a hundred or two or three hundred
a hundred or two or three hundred species of birds have been killed by
species of birds have been killed by
species of birds have been killed by human activity in the last five hundred
human activity in the last five hundred
human activity in the last five hundred years and the figures are debated it’s
years and the figures are debated it’s
years and the figures are debated it’s something like from half a species to
something like from half a species to
something like from half a species to four species each year on average we
four species each year on average we
four species each year on average we don’t know for sure because of course
don’t know for sure because of course
don’t know for sure because of course people didn’t record everything now how
people didn’t record everything now how
people didn’t record everything now how do we scale this up to get a global
do we scale this up to get a global
do we scale this up to get a global figure from birds on the one hand to all
figure from birds on the one hand to all
figure from birds on the one hand to all of life and the way it was done was
of life and the way it was done was
of life and the way it was done was simply to say we know how many species
simply to say we know how many species
simply to say we know how many species of birds there are alive today there are
of birds there are alive today there are
of birds there are alive today there are 10,000 and the initial estimates for the
10,000 and the initial estimates for the
10,000 and the initial estimates for the diversity of all of life were 100
diversity of all of life were 100
diversity of all of life were 100 million so you scale from for a day
million so you scale from for a day
million so you scale from for a day upwards and that brings you up to this
upwards and that brings you up to this
upwards and that brings you up to this figure of a hundred per day by
figure of a hundred per day by
figure of a hundred per day by multiplying up many times 40,000 loss
multiplying up many times 40,000 loss
multiplying up many times 40,000 loss per year a hundred per day based on that
per year a hundred per day based on that
per year a hundred per day based on that extreme high bird figure at the other
extreme high bird figure at the other
extreme high bird figure at the other end the lowest estimate is something
end the lowest estimate is something
end the lowest estimate is something like one species per day this is because
like one species per day this is because
like one species per day this is because we’re not sure about that bird figure so
we’re not sure about that bird figure so
we’re not sure about that bird figure so we could take a lower
we could take a lower
we could take a lower estimate and also we’re actually not
estimate and also we’re actually not
estimate and also we’re actually not sure about the diversity of life today
sure about the diversity of life today
sure about the diversity of life today either some of you will know that you
either some of you will know that you
either some of you will know that you you might think we would name every we
you might think we would name every we
you might think we would name every we would have named every species we would
would have named every species we would
would have named every species we would know that we don’t you can look at
know that we don’t you can look at
know that we don’t you can look at Wikipedia there are thousands and
Wikipedia there are thousands and
Wikipedia there are thousands and thousands of pages describing all the
thousands of pages describing all the
thousands of pages describing all the living species but there are so many
living species but there are so many
living species but there are so many living species that we have never
living species that we have never
living species that we have never discovered never described aren’t there
discovered never described aren’t there
discovered never described aren’t there in wikipedia so there is that
in wikipedia so there is that
in wikipedia so there is that uncertainty 100 million 10 million we
uncertainty 100 million 10 million we
uncertainty 100 million 10 million we don’t know those are the estimates of
don’t know those are the estimates of
don’t know those are the estimates of numbers of species going extinct each
numbers of species going extinct each
numbers of species going extinct each day one per day 100 per day do we worry
day one per day 100 per day do we worry
day one per day 100 per day do we worry about that this is where paleontology
about that this is where paleontology
about that this is where paleontology comes in first because fossil data
comes in first because fossil data
comes in first because fossil data allows us to calculate what would be the
allows us to calculate what would be the
allows us to calculate what would be the normal rate of extinction species do go
normal rate of extinction species do go
normal rate of extinction species do go extinct so this this politician over
extinct so this this politician over
extinct so this this politician over here was quite right and but was Al Gore
here was quite right and but was Al Gore
here was quite right and but was Al Gore right we don’t know you know he was
right we don’t know you know he was
right we don’t know you know he was giving that high figure maybe somewhere
giving that high figure maybe somewhere
giving that high figure maybe somewhere in between but what is the norm is one a
in between but what is the norm is one a
in between but what is the norm is one a day okay
day okay
day okay doesn’t sound too many if there are
doesn’t sound too many if there are
doesn’t sound too many if there are millions and millions of species it is
millions and millions of species it is
millions and millions of species it is far too high we know that the average
far too high we know that the average
far too high we know that the average duration of a species is two million
duration of a species is two million
duration of a species is two million years they originated they go extinct
years they originated they go extinct
years they originated they go extinct two million years and that means as they
two million years and that means as they
two million years and that means as they come and go on average we would expect
come and go on average we would expect
come and go on average we would expect the extinction of five million species
the extinction of five million species
the extinction of five million species every million years which is five
every million years which is five
every million years which is five species per year so that does contrast
species per year so that does contrast
species per year so that does contrast remarkably even at the lowest estimate
remarkably even at the lowest estimate
remarkably even at the lowest estimate of human impact five hundred species per
of human impact five hundred species per
of human impact five hundred species per year is 100 times the normal rate of
year is 100 times the normal rate of
year is 100 times the normal rate of five per year and at the bottom there is
five per year and at the bottom there is
five per year and at the bottom there is the dodo just in case you weren’t sure
the dodo just in case you weren’t sure
the dodo just in case you weren’t sure what it looked like so I want to look at
what it looked like so I want to look at
what it looked like so I want to look at two other topics briefly one is risk and
two other topics briefly one is risk and
two other topics briefly one is risk and so one of the questions we would have
so one of the questions we would have
so one of the questions we would have estimating the total numbers is one
estimating the total numbers is one
estimating the total numbers is one thing we have learned that we are
thing we have learned that we are
thing we have learned that we are impacting life harder than we should be
impacting life harder than we should be
impacting life harder than we should be human activity is causing extinction
human activity is causing extinction
human activity is causing extinction what about risk it’s easy to say of
what about risk it’s easy to say of
what about risk it’s easy to say of course the dodo was stupid it lived on
course the dodo was stupid it lived on
course the dodo was stupid it lived on one island it just stood around and
one island it just stood around and
one island it just stood around and allowed itself to be hit on the head to
allowed itself to be hit on the head to
allowed itself to be hit on the head to an extent we worry about elephants we
an extent we worry about elephants we
an extent we worry about elephants we worry about pandas we worry about many
worry about pandas we worry about many
worry about pandas we worry about many individual species many of those have
individual species many of those have
individual species many of those have high risk factors so for example an
high risk factors so for example an
high risk factors so for example an elephant is very large this means they
elephant is very large this means they
elephant is very large this means they need a lot of food they need a lot of
need a lot of food they need a lot of
need a lot of food they need a lot of territory to walk around and so it’s
territory to walk around and so it’s
territory to walk around and so it’s much harder to keep a sufficiently large
much harder to keep a sufficiently large
much harder to keep a sufficiently large population of elephants breeding and
population of elephants breeding and
population of elephants breeding and successfully in the wild we don’t need
successfully in the wild we don’t need
successfully in the wild we don’t need to worry about rats for example they’re
to worry about rats for example they’re
to worry about rats for example they’re small and there’s lots of them so body
small and there’s lots of them so body
small and there’s lots of them so body size is one risk factor being big is not
size is one risk factor being big is not
size is one risk factor being big is not a good thing if you want to survive as a
a good thing if you want to survive as a
a good thing if you want to survive as a species what about the Panda they’re not
species what about the Panda they’re not
species what about the Panda they’re not so huge they’re about human sized they
so huge they’re about human sized they
so huge they’re about human sized they have a specialized diet there they have
have a specialized diet there they have
have a specialized diet there they have evolved into a crazy position as you
evolved into a crazy position as you
evolved into a crazy position as you know they are eating bamboo without the
know they are eating bamboo without the
know they are eating bamboo without the real ability to consume it properly if
real ability to consume it properly if
real ability to consume it properly if that food supply disappears they’re
that food supply disappears they’re
that food supply disappears they’re stuck so secondly restricted diet is a
stuck so secondly restricted diet is a
stuck so secondly restricted diet is a problem the third one is shown by the
problem the third one is shown by the
problem the third one is shown by the dodo
dodo
dodo if you live in only a very small
if you live in only a very small
if you live in only a very small geographic area rather than over the
geographic area rather than over the
geographic area rather than over the whole world you are at risk so there are
whole world you are at risk so there are
whole world you are at risk so there are three things to be medium size or small
three things to be medium size or small
three things to be medium size or small if you want to survive a broad diet
if you want to survive a broad diet
if you want to survive a broad diet willing to eat everything and living
willing to eat everything and living
willing to eat everything and living over the whole world so that includes
over the whole world so that includes
over the whole world so that includes human beings and rats and cockroaches
human beings and rats and cockroaches
human beings and rats and cockroaches they will survive and many other species
they will survive and many other species
they will survive and many other species will not survive whatever we do so a
will not survive whatever we do so a
will not survive whatever we do so a risk is something we can determine from
risk is something we can determine from
risk is something we can determine from the present day but also we can test
the present day but also we can test
the present day but also we can test when we look at mass extinctions in the
when we look at mass extinctions in the
when we look at mass extinctions in the past so this is where we come back to
past so this is where we come back to
past so this is where we come back to paleontology because I think most people
paleontology because I think most people
paleontology because I think most people here know that the end of the dinosaurs
here know that the end of the dinosaurs
here know that the end of the dinosaurs was marked by a mass extinction many
was marked by a mass extinction many
was marked by a mass extinction many millions or thousands of species died
millions or thousands of species died
millions or thousands of species died out rather rapidly because of that
out rather rapidly because of that
out rather rapidly because of that extinction definitely was largely the
extinction definitely was largely the
extinction definitely was largely the impact of a meteorite a huge asteroid
impact of a meteorite a huge asteroid
impact of a meteorite a huge asteroid maybe ten kilometers across and the
maybe ten kilometers across and the
maybe ten kilometers across and the model for extinction of the dinosaurs
model for extinction of the dinosaurs
model for extinction of the dinosaurs sixty-six million years ago was the
sixty-six million years ago was the
sixty-six million years ago was the asteroid hit the earth this is
asteroid hit the earth this is
asteroid hit the earth this is unpredictable when this may happen or
unpredictable when this may happen or
unpredictable when this may happen or not it penetrated into the crust it is
not it penetrated into the crust it is
not it penetrated into the crust it is vaporized and all of that rock of the
vaporized and all of that rock of the
vaporized and all of that rock of the asteroid plus the crust that it had
asteroid plus the crust that it had
asteroid plus the crust that it had penetrated turned into rocks and dust
penetrated turned into rocks and dust
penetrated turned into rocks and dust mainly dust this was thrown up high into
mainly dust this was thrown up high into
mainly dust this was thrown up high into the atmosphere and why
the atmosphere and why
the atmosphere and why all run the earth blacking out the Sun
all run the earth blacking out the Sun
all run the earth blacking out the Sun and so that you get two effects there
and so that you get two effects there
and so that you get two effects there are no light no heat so there was a
are no light no heat so there was a
are no light no heat so there was a cessation of photosynthesis the plants
cessation of photosynthesis the plants
cessation of photosynthesis the plants died there was darkness and cold so this
died there was darkness and cold so this
died there was darkness and cold so this was not good for dinosaurs and other
was not good for dinosaurs and other
was not good for dinosaurs and other groups that enjoyed the warm climates
groups that enjoyed the warm climates
groups that enjoyed the warm climates and so you get extinction and you might
and so you get extinction and you might
and so you get extinction and you might think of course what do we learn from
think of course what do we learn from
think of course what do we learn from this yes that’s all very well but that’s
this yes that’s all very well but that’s
this yes that’s all very well but that’s not something we can do anything about
not something we can do anything about
not something we can do anything about really
really
really and indeed asteroids do come close to
and indeed asteroids do come close to
and indeed asteroids do come close to the Earth from time to time earlier this
the Earth from time to time earlier this
the Earth from time to time earlier this week one did luckily it didn’t hit the
week one did luckily it didn’t hit the
week one did luckily it didn’t hit the earth we can’t really prepare but the
earth we can’t really prepare but the
earth we can’t really prepare but the key point is that the other mass
key point is that the other mass
key point is that the other mass extinctions in the history of life were
extinctions in the history of life were
extinctions in the history of life were not caused by impact they were caused by
not caused by impact they were caused by
not caused by impact they were caused by climate change immediately you can see
climate change immediately you can see
climate change immediately you can see now how that matters I’ll briefly
now how that matters I’ll briefly
now how that matters I’ll briefly characterize one of them that I have
characterize one of them that I have
characterize one of them that I have worked upon at the end of the Permian
worked upon at the end of the Permian
worked upon at the end of the Permian period 250 million years ago there was
period 250 million years ago there was
period 250 million years ago there was another major extinction this was before
another major extinction this was before
another major extinction this was before the dinosaurs and the sequence of events
the dinosaurs and the sequence of events
the dinosaurs and the sequence of events was that massive volcanoes erupted in
was that massive volcanoes erupted in
was that massive volcanoes erupted in Russia they were so huge that they
Russia they were so huge that they
Russia they were so huge that they poured out enormous amounts of lava of
poured out enormous amounts of lava of
poured out enormous amounts of lava of course but more importantly they’ve
course but more importantly they’ve
course but more importantly they’ve poured out gases into the atmosphere
poured out gases into the atmosphere
poured out gases into the atmosphere including carbon dioxide and carbon
including carbon dioxide and carbon
including carbon dioxide and carbon dioxide is as famous as a greenhouse gas
dioxide is as famous as a greenhouse gas
dioxide is as famous as a greenhouse gas meaning it heats the atmosphere we have
meaning it heats the atmosphere we have
meaning it heats the atmosphere we have primary evidence that around the equator
primary evidence that around the equator
primary evidence that around the equator ocean temperatures warmed up to 40
ocean temperatures warmed up to 40
ocean temperatures warmed up to 40 degrees plus so this is like a very warm
degrees plus so this is like a very warm
degrees plus so this is like a very warm shower you might think that’s okay maybe
shower you might think that’s okay maybe
shower you might think that’s okay maybe for ten minutes but not for day after
for ten minutes but not for day after
for ten minutes but not for day after day after day and so life had to
day after day and so life had to
day after day and so life had to progressively flee out of the equatorial
progressively flee out of the equatorial
progressively flee out of the equatorial zones it became crowded at the poles and
zones it became crowded at the poles and
zones it became crowded at the poles and there was great extinction so we learned
there was great extinction so we learned
there was great extinction so we learned from that that carbon dioxide and global
from that that carbon dioxide and global
from that that carbon dioxide and global warming can cause extinction
warming can cause extinction
warming can cause extinction whatever the cause of that carbon
whatever the cause of that carbon
whatever the cause of that carbon dioxide whether it comes from volcanoes
dioxide whether it comes from volcanoes
dioxide whether it comes from volcanoes or human activity so we’ve learned three
or human activity so we’ve learned three
or human activity so we’ve learned three things that we can illustrate and use
things that we can illustrate and use
things that we can illustrate and use for predicting into the future what may
for predicting into the future what may
for predicting into the future what may happen to life we’ve learned that we can
happen to life we’ve learned that we can
happen to life we’ve learned that we can calculate the rate of extinction by
calculate the rate of extinction by
calculate the rate of extinction by looking at historical extinctions and at
looking at historical extinctions and at
looking at historical extinctions and at that rate of extinction even at the
that rate of extinction even at the
that rate of extinction even at the minimal figures
minimal figures
minimal figures is at least 100 times what it ought to
is at least 100 times what it ought to
is at least 100 times what it ought to be secondly we’ve learned something
be secondly we’ve learned something
be secondly we’ve learned something about risk which species are most at
about risk which species are most at
about risk which species are most at risk of extinction and I think that’s
risk of extinction and I think that’s
risk of extinction and I think that’s fairly straightforward but we need the
fairly straightforward but we need the
fairly straightforward but we need the evidence to be able to argue the case
evidence to be able to argue the case
evidence to be able to argue the case and thirdly we’ve learned that the whole
and thirdly we’ve learned that the whole
and thirdly we’ve learned that the whole history of the earth records they’re a
history of the earth records they’re a
history of the earth records they’re a rich record of of climate change we
rich record of of climate change we
rich record of of climate change we don’t need to do experiments we don’t
don’t need to do experiments we don’t
don’t need to do experiments we don’t need to imagine what what a world would
need to imagine what what a world would
need to imagine what what a world would be like without the polar ice caps it
be like without the polar ice caps it
be like without the polar ice caps it has existed and we can study it so to
has existed and we can study it so to
has existed and we can study it so to conclude my aim has not been simply to
conclude my aim has not been simply to
conclude my aim has not been simply to spread doom and gloom and but to
spread doom and gloom and but to
spread doom and gloom and but to indicate that we have the power to
indicate that we have the power to
indicate that we have the power to change and in order to change we have to
change and in order to change we have to
change and in order to change we have to accept reality along the lines I’ve been
accept reality along the lines I’ve been
accept reality along the lines I’ve been mentioning and we have to ask the right
mentioning and we have to ask the right
mentioning and we have to ask the right questions about what we should do and in
questions about what we should do and in
questions about what we should do and in order to decide what we should do that
order to decide what we should do that
order to decide what we should do that we need to use evidence and the some
we need to use evidence and the some
we need to use evidence and the some great evidence comes from the history of
great evidence comes from the history of
great evidence comes from the history of the earth and the history of life thank
the earth and the history of life thank
the earth and the history of life thank you very much
you very much
you very much [Applause]
[Applause]
[Applause] [Music]
”
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