The Organism as Subject and Object of Evolution
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The Organism as Subject and Object of Evolution


good evening good evening I’d like to
welcome all of you to the if this is working I’d like to welcome you all to
the second night of the alarm lectures hosted by the Santa Fe Institute and to
welcome all of you on behalf of the Institute I’m Doug Irwin I’m a research
scientist at the Smithsonian in Washington here for you on sabbatical
and looking forward to this evening’s talk the second of three in the lecture
series this year Wow I assume most of you were probably through last night you
know that the elections are being even this year by Professor Richard Lewontin
the Alexander Agassiz professor at the Museum of Comparative Zoology at Harvard
University dr. ludington is one of the most noted population geneticists and
evolutionary biologists of his generation and we’re enormously happy to
have him tender this year the title of this evening’s lecture is the organism
as a subject and object of evolution I’m particularly looking forward to this
component of the three lectures because it will touch on some very different
ways of looking at the evolutionary process that in my view and you I think
if any evolutionary biologists will substantially change the way we look at
many of the important events in the history of life and so without further
ado professor bruce diluent am I switched on I’m switched on for those of you who are here last night
I want to apologize for being up here now instead of down there where I belong
but a lot of people couldn’t hear me especially when I dropped my voice at
the end of sentences at the end of jokes so I’ve been convinced that I better
stand up here and try to talk to you but you understand that these lights are in
my eyes and I can’t see you and because I can’t see you it’s hard for me to talk
to you no no that’s true so no no no no definitely
you won’t hear me if I’m down there so we’ll see what we can do up here we’ll
take a vote at the end and see what to do about tomorrow night what I want to talk about tonight
essentially concerns two very powerful metaphors and biology which are which
are relevant to our understanding of the evolutionary process the one I chiefly
want to talk about is the metaphor of adaptation the notion that organisms
during evolution adapt to the environment I want to challenge that
metaphor it is a metaphor the word adaptation means literally to be changed
in order to fit something that is pre-existing like when you go to Europe
and you they have crazy two hundred and ten volts or something you have to carry
an adapter with you so that your hairdryer works
keys are adapted to fit locks add active means literally made fit to act to
something that already exists and indeed Darwin’s use of the word fit as in
Fitness has to be taken literally he really meant that the organism fit into
some pre-existent structure in the world what ecologists now called the
ecological niche of the organism and the whole notion of niche of some sort of
hole in the world and the ex world into which the organism fits
rather like an antibody antigen relationship if you’re a molecular
biologist that will you’ll appreciate that you get you get the point and I
want to challenge that notion that organisms evolved to fit pre-existing
ecological niches and that the whole metaphor of adaptation is the wrong
metaphor and I want to propose a different way of understanding the
evolutionary process this does not challenge the notion of natural
selection but challenges the notion that what natural selection does is to add
apt organisms to a previously existing world outside of them before I do that I
have to deal briefly I hope because I need a lot of time for the other I’ll
try to get it through it briefly with another metaphor which is a very
powerful one or another set of metaphors having to do with genes and the role of
genes in the in the development of organisms if you are so unfortunate as
to read the New York Times or other kinds of reports of of science in the
national press or textbooks for that matter you will be impressed with the
fact that genes make organisms everybody knows that indeed I heard what is the
person who is perhaps the leader or one of the great leaders of modern molecular
biology giving a speech at the hundredth anniversary of the death of Darwin I was
getting something commemorating not celebrating but commemorating 100th
anniversary and he was the keynote speaker for some curious reason and
among the things he said was if you give me we’re at the stage in biology where
if you give me the complete DNA sequence of an organism and a large enough
computer I could compute the organism now I have to say that despite his great
contributions to biology that’s just rubbish it’s rubbish because no organism
computes itself from its own DNA there’s missing
information there’s very important missing information and DNA and the and
the MV and the state of the genes is not sufficient to specify the organism and
I’m going to spend a few minutes on that because it’s quite important to get away
from that kind of deterministic terminus view of organism in order to go on to
the more important question or not more important but the one I’m trying to
develop tonight so the first thing I want to convince you of is that genes do
not make organisms that organisms are a consequence that develop I’ve got to
coming at the development of organisms I don’t have time tonight to discuss that
metaphor development but development means an unfolding coming out of the
envelope and for those of you who are Hispanic
it’s dis out of oil and unrolling in German it’s an Vikram you know what N
pickles and fickle if you have a ball of yarn and you throw it on the ground it n
pickles that’s what that victory is it’s an unrolling or unfolding of a
preexistent pattern and organisms do not develop either it is some of you may be
aware of the fact that there was a great struggle in the history of biology
between the so called pre formation is who believed that the organisms already
contained in miniature in the sperm and you sometimes see pictures of little men
huddled inside the sperm the egg was only nutritive it didn’t have any
important well that was the view the reorganization sperm and all that little
organism did was to get bigger that was pre formation ISM whereas epigenesis
said no no that’s not right is a process of epigenesis in which the organism
actually comes into form and creates new forms during its process of development
and the history of biology says of course no fool believes is a little man
and sperm and that it’s the epigenesis who won the struggle that’s what all the
history of science books tell us but it’s not true it’s the pre formation as
to on the struggle because i have to ask you to consider what is the difference
between the claim that the sperm has a little man in it
and if the sperm has the complete information necessary to make the little
man it’s a matter of mechanics but not very interesting difference the
important difference is that it doesn’t there is no unrolling of a preexistent
fixed program to make the organism and we need to get that straight before we
go under the more important or the other point now to try to convince you of that
and people say well of course everybody knows the environment has some role
after all even if you have genes that would make you fat if you starve
yourself you’d be thin so there must be environments in which no matter you know
no matter how fat your genes are you’ll be thin but that view is contained in a
general view of the relationship between organism and environment which contained
in the first I think susan deserves our know no wiggling please no no it seems
dealing I take this this is a this is taken from a famous paper in the Harvard
education will review by Arthur Jensen who wrote about IQ and it shows that
notion yes the environment matters in what your IQ is this is one genotype
which if it’s deprived as a low IQ and if it’s enriched has a higher one sorry
the next one is another genotype which is above that one and so on
no there’s the differences in genes are the differences between the curves the
environment makes that difference right and the notion is that if you have lousy
genes you have the worst possible IQ no matter what environment you’re in even
though the environment is making the IQ higher the order in which these are
remains the same is that a point clear a bad environment makes poor IQ but if
you’ve got good genes you still have a better IQ then than if you don’t
that’s not the truth and you really have to abolish this notion of the
relationship between organism gene and environment that’s wrong and we should
remove it instantly from the from the consciousness of our audience
thank you the truth is been known for a long time
by experimental biologists and the most dramatic demonstration of what the real
truth is about the relationship between gene environment and organism are a set
of cloning experiments cloning experiments done in the 1930s
you may not realize but cloning has been going on for a long time because they’re
a bunch of organisms called plants which are absurdly easy to clone you take a
scissors and you clip them into three pieces and you stick the three pieces in
the ground and lo and behold they grow up into three copies of the same genes
and you can ask the question what would happen if I took one piece of the plant
and stuck at it in one environment another piece in another environment
another piece of another environment what would they look like and the most
famous set of experiments like that were done by colleagues in California claws
and kickin hi-c on a plant called a Kalia
and I want to show you photographs of the results they got because these
contain the truth about the relationship between internal and external
information in the development of organisms and Susan if we could have
this one please and that orientation these are photographs or they’re
tracings of photographs of the results if if you could move it down a bit yeah
great thanks a lot what’s shown here are seven different plants taken from the
wild cut into three pieces one piece grown at low elevation one piece grown
at medium elevation and one piece grown at high elevation in the Sierras this is
a different plant a different set of genes low elevation medium elevation
high elevation so you go up this way you’re changing the environment you go
this way you’re changing the genes is that clear to everyone what the very
simple experiment and they organized it in such a way that they put the plants
in descending order of their growth at low elevation and now let’s see what
happened in medium elevation well the very best grower at low elevation turned
out to be lousy oscura medium elevation it turned out to be they’re
actually the best at high elevation the second-best was probably the third best
at the third worst that medium elevation and just about the worst at high
elevation and so on if you look at them what you see is there’s no relationship
between the ordering of growth rate and growth pattern at the low elevation to
the one at medium or the one at high there’s no in fact if you measure these
there’s no correlation at all between the growth in the three environments
therefore there’s no predictability it is not the case that the thing that
grows best here will also grow best to your investor on the contrary there’s no
predictability at all that is to say Jensen’s view of the
world is not right what actually happens is that the curves showing plant and
also flowering shows us peculiar result if you plotted the plant height against
the environment you would find that the curves crossed each other for example
let me ask you which of these genetic types grows best I challenge my my my
developmental biologist to take out his computer I’ll give you the complete DNA
sequence of all of these and predict please which one will grow best period
and the answer is you can’t because you have you’ve lost the important piece of
information namely in what environment of the organisms grown and if I don’t
know that I don’t know the answer to the question and that’s the big truth the
first big truth about the relationship between development and and and genes
namely that organisms don’t develop that I say they don’t unfold a preexistent
program they are in the constant situation of of creation during the
process of I don’t know what to call it the only way we have is development
during their life history so that’s the chief point I want that’s point a of the
chief point away point B is that even if I tell you the genes and the environment
I still haven’t got all the information I need to specify the organism there’s a
third fee that third feature you can convince
yourself of if when you go home you will all please go to the mirror hold up your
hands and look at the fingerprints on your left and right hands and you will
find for the vast majority of you that their fingerprints on your left hand are
quite different from the fingerprints on your right hand in fact they look like
come up with somebody completely different Francis Gault one of the most
famous of the early geneticists I’ve seen his fingerprints and they’re just
utterly different on one hand than the other some of you will have very similar
ones on both sides not identical but similar if I count the number of hairs
under the armpits of fruit flies on the average I have the same number on wing
pits I guess I should call it on the left hand side and the right hand side
but one fly will have seven here and five there and the other one will have
six here and four there and so there’s what’s called fluctuating asymmetry now
what is the origin of fluctuating any symmetry the genes are the same on the
left on the right hand side the environment in which your hands
developed in those crossed arms in the womb of your mother you could hardly say
well as an average difference in environment on the left on the right
hand side doesn’t seem reasonable yet they come out very different what is the
origin of that asymmetry and the answer briefly I would give a whole lecture on
that if I had four lectures instead of three is that the molecules in your
cells are in very small numbers like there are three of those and seven of
those and five of those and they’re in particular places in the cell and for
the cell to divide and undergo its development after use the word
development it’s it’s change those molecules have to be in the right place
at the right time to interact with each other and there’s a lot of random noise
inside the cell so randomness comes into play again and the consequence of that
random noise and we have a lot of experimental evidence about it as well
as as theoretical work is that two cells which have identical genes and are side
by side in the organism or inequivalent places on the left and right hand side
will not divide at the same time will not move in the same way
we’ll lose different things if I saw a single bacterial cell into a huge vat of
rich culture medium after about an hour it will divide into two then those two
will divide into two each to produce four but they won’t do it simultaneously
first one will divide and then a little later the other one will divide and then
if I take those four first one will divide and then another one and then
another one why is it that those cells are not dividing simultaneously after
all they’re living in a in a huge vat of rich uniform medium which is being
stirred so no environmental differences and there are no genetic differences
after the first three or four generations of cell division there are
no mutations enough can’t be very many if any what’s the source of that
variation the source again is if you had to have seven molecules in order to
divide of a particular kind after the vision one cell has four and when the
cell has three at best and therefore it takes different times for the two cells
to come up to full complement before they can divide again so random
variation what’s generally called developmental noise is very important
for organisms and if you want to see an example of developmental origins the
last thing I’m going to say about this sub issue let me show you a case history
about developmental noise which some of you may even recognize could we have
that one I don’t know how many people in this room are old enough to know who
this is these are the famous Dionne quintuplets
identical quintuplets born to a rural poor rural family in Ontario these girls
were not only genetically identical but as a consequence of the entrepreneurship
of the doctor who delivered them together with the with the province of
Ontario were brought up in a kind of zoo in which people paid to watch them and
during their upbringing notice they were all identically clad identically shod
they’re identically quaffed every effort was made to enforce identity of
environment on these five girls who are also genetically identical so if the
environment is identical I mean it’s criminal what was done to them and
not until they reach puberty could they rebel against that they were literally
in a kind of luxurious prison in which you could go and watch them being being
homogenized under those circumstances one would expect that when they grew up
they did all be identical right but as a matter of fact when they all grew up
they didn’t turn out to be identical two of them tried a religious vocation one
of them failed one succeeded three got married two had children one died at the
age of now I’m going to have to throw a number because I it’s too long since I
read the book 18 of momento disorder having a mental disorder and died
another one probably committed suicide but she is pretty clear she committed
suicide at another age and the three survivors have lives as different from
one another as any three girls growing up in a poor rural Ontario family could
have and I want to show you a picture of the three girls no longer girls who are
very angry about what was done to them but who are very different from one
another in their life histories so the five people had very different life
histories including life and death including mental disorder including a
religious interest and so on and they are holding a sign and says we want
justice not charity I mean they want to be paid back for what was done to them
but you notice they look alike I mean sure there you can tell her sisters but
I wouldn’t have guessed more than that well you know okay even identical
triplets their noses are the same shape they’ve accentuated the differences
among them by cutting their hair differently and so on and so forth but
what I’m trying to emphasize to you is that identical genes and identical
environment did not make identical individuals they made individuals who
differ what’s the source of that why did some become nuns and others not why did
some marry and others not why did some have children and others not
why did some die early and some died and then some haven’t died presumably again
this is a kind of developmental noise in the nervous system a developmental noise
in the in the endocrine system and so on which made them different
some way okay I just thought you’d like a concrete view of that rather than just
grass okay so what organ so the story about all right no let’s leave it on for
a sec because I want to sum it up if I may buy a picture no forget yeah here it
is first this one if I may and then that
one the first picture shows three different
plans that one can imagine for organisms in plan one the genes matter there are
different environmental factors there the input into the development of the
organism there’s Plan A which is one set of genes and Plan B which is a different
set and so plan a leads to one kind of organism and plaid and B leads to
another irrespective of these environmental factors which are general
inputs that’s the model of genetic determination which I’m challenging the
second one is the opposite namely is environmental determination in the genes
only provide the sort of generalized input so you have environment one which
puts you on that pathway environment to B which puts on that pathway there are
general genetic rules genes matter here but the difference between organisms in
this scheme is entirely environmental right whether you decide to be a Baptist
or or an Episcopalian the usual story if we could sort of just raise it a little
bit Susan yeah is to put them both together and say genes and environment
both matter here’s gene genotype a and gene Type B here’s environment type 1
and type 2 and they come together to produce different kinds of organisms and
the result is a unique combination of genes and environment and you can’t
predict just from one but what I’m trying to tell you is it’s even more
complicated than that and that’s the last picture that most
development is really like this there are different types of gene sets there
are different types of environments but even those
combinations of gene and environment do not specify organism but there’s
variation among the organisms even when they have identical genes and dental in
varmint and that’s the noise component and most of what we know about higher
organisms and even in bacterial develop a division rotor tell us that this is
the story of organisms in their relationship to genes and environment
now that’s just sort of the beginning of what I want to say we need to get that
straight before we get to the big message and I that’s why I’ve spent some
time on it the relationship between gene organism and environment events now I
want to get to the big metaphor and we could turn it off now I think the
metaphor of adaptation the notion that evolution is the process by which
organisms come to fit the external environment which is there and they move
toward it and finally fit in that’s the notion environmental of the ecological
niche and I want as a kind of mantra which everyone should repeat every night
before going to bed just as there is no organism without an environment there is
no environment without an organism that is to say we should not talk about V
environment there is no V environment there is an environment for every
organism and I claim that that environment is not the result of the
organism moving toward it because that means it would have pre-existed the
environment is what is as the word suggests on V Hall around the organism
but what decides what’s around the organism it is the organism who if I may
put it that way decides what’s around it which
determined what that determines the actual nature of what surrounds it let
me give you a practical example of the error of trying to describe an
ecological niche in the world for an orgasm that you’ve never seen that’s
what you’d have to do you’d have to go out and divide up the world into bits
and people say oh there’s an unoccupied niche there’s an unoccupied niche
there’s an occupied one there’s a most of them are unoccupied of course and
you’d have to write them out I defy anyone of you
to describe the nisha of an organism you haven’t seen all you could make it up
out of your head but but somebody actually tried to do that in a very
interesting way when the Mars Lander was being developed there were two plans for
Mars Landers to detect life on Mars one was Josh later Berg’s idea which
everybody thought was absurdly naive and that was to use a to send up a long
sticky tongue the tongue would unroll get some dust from Mars come back in and
there’d be an electron microscope which would look at the dust and we’d see the
result of what was being seen about the electron microscope and if we saw things
wiggle we’d know there was life on Mars well everybody says that’s silly you
know wiggling what kind of a definition of life is that that’s not scientific so
instead they made up a scientific way of detecting life on Mars although by the
way the wiggling is what paleo ecologists paleo botanists do all the
time when they’re trying to find out when life originated they look at rocks
and see if there are things in them that look like they wiggled the scientific
way was about the Mars Lander that was actually made was not an electron
microscope and a long sticky tongue it was a big vacuum cleaner a tank vacuum
cleaner with a long hose the hose went out of the lander sucked up some dust
the dust went into the vacuum cleaner inside the vacuum cleaner tank was am it
was it was a medium which would allow any microorganisms to grow in it by
breaking down sugar and the carbon in that medium was radioactively-labeled so
when the little beasts broke them the sugar and the bits in the molecular bits
carbon dioxide would be evolved the carbon dioxide would be detected by a
co2 a radioactive detector and down on earth they would be B P P P P P P P as
the as the the counter so they sent the thing and that’s what it did it unrolled
and and all hell broke loose at Mission Control because sure enough the number
of counts per second began to rise and rows and rows and rows and I wish I had
been there I mean they must have been out of their wigs
and then suddenly bang it shut down just like that and everybody thought oh well
the machine stopped working but they did all the testing machine was working but
somehow life had stopped instantly like that
no more co2 so they had a meeting at MIT I remember the meeting in which people
discussed this result and I can only caricature it by saying they took a vote
and the vote was there’s no life on Mars the vote was essentially that this must
have been some sort of chemical reaction catalyzed by the dust particles of
finely divided clay particles that were picked up because as we know very fine
particles will catalyze various chemical reactions and subsequently that reaction
was produced in the laboratory on earth I mean you can do that now what’s the
problem with this experiment the problem of this experiment is that in order to
detect life they created an ecological niche for
that life right I mean a stuff that the life could live in but what made them
think that organisms on Mars had that particular ecological niche in fact most
microorganism not most but many a microorganism on earth don’t break down
glucose most of them are not or many of most many of them are not aerobic
they’re a sulphur fixing bacteria I mean there’s all kinds of crazy stuff how do
they know that life on Mars like to eat sugar or gave all or or broke it down
and put out co2 no way in fact if I had to choose knowing life on Earth the
majority of organisms on Earth will show evidence of wiggling or evidence of some
kind of shape cellular shape as opposed to the majority of organisms behaving
that way this is an error of inventing an ecological niche before you’ve seen
the organism that’s in it and so I come back to the main claim that the
ecological niche of an organism does not exist without the organism the physical
world exists the environment in that sense of temperature and moisture not
locally but I mean globally exists without those organisms although they
have an effect on it as you know you reminded
every day that you’re putting out all that co2 and changing the world’s
so-called environment what is it that organisms do that
I claim constructs the environment so on the claim I want to make is that
organisms do not fit into pre-existing environments that organisms in their
life activities in their physiology and metabolism and behavior construct around
themselves a world now the first thing organisms do by their sensuous like
activity or the first thing I’ll list is that they determine by their activities
both their gross activities and their metabolic activities what aspects of the
external world are relevant to them and what aspects are irrelevant to them so
for example if I when we lived in Britain there were birds that took
snails and wrapped them on rocks and roof tiles to break the snails so they
could eat them and then there were crows who didn’t do that they had another way
of living in and great tits which they now those roof tiles and those stones in
the ground were physically proximate to all the birds in our garden but they
were part of the environment of the thrushes that broke snails on those
rocks but they were irrelevant to the life of the other animals for those
other birds whether rocks are part of the environment of a bird is that is a
question of whether they the birds activities make those rocks relevant to
its life activities because after all there’s all sorts of things around which
are lying around in the in the in the geographical vicinity of an organism
which the organism doesn’t know anything about and are irrelevant to that
organism and others which the organism has made relevant to it so the first
thing that organisms do is to make things relevant to it twigs are relevant
to a bird that makes nests out of twigs and grass through an organism makes
nests out of grass and holes and trees are relevant to woodpeckers but not to
other kinds of animals and so on so you get the point what is relevant is
determined by the life activity organs and the life activity the organism is
influenced why wouldn’t say determined but influenced by its genes so I could
just as well say that the genes make the environment in the same sense that they
make the organism I mean I’d say that they that they’re the fact that one bird
has stones as part of its environment and another bird doesn’t is a difference
in their DNA so I want to sort of go around come back again okay so they
decide what’s relevant secondly every organism every organism in the world
every species in the world constructs literally constructs a world around
itself from bits and pieces not only deciding what’s relevant but putting the
relevant parts together in a way that is physiologically a meaningful and
relevant to the organism we constructed this and it is indeed an important part
of our environment we would not be sitting here having this lecture
outdoors tonight that’s for sure and you all clear the fact that bees make bee
hives and and and and moles and bury in the ground and make tunnels and so
everybody knows those examples but those we think of as special examples very
smart or very clever animals like ants and so on but that’s not the case the
cases that every organism is constructing the world around itself
there was a man who went around at one time many years ago showing photo movie
moving pictures of living organisms people among them taken with what I call
schlieren optics Sharon optics a special form of optics which show differences in
specific gravity well actually not specific gravity but but but like
transmitting properties of gases through which the light is passing so that you
see like heat rising from a road that sort of thing and when he took pictures
with schlieren optics what did he see and what he showed to us
every animal and plant that was photographed he took a lot of
photographs of people and so let’s talk about us have around them surrounding
them a boundary layer of moist warm air moister and warmer that these are
terrestrial organisms I’m talking about then the air outside moreover that air
for us is rising up over our bodies and over the tops of our heads and streaming
off the top every one of you is sitting not in this room in some broad sense but
in a little encapsulation of moist warm air which you are creating at every
moment by your metabolism you make the heat and you make the metabolic water
that comes out in the form of this therefore you are carrying around with
you your own little world in which you’re living and not going to carry
yarn with you but every little animal or thing that’s living on you I don’t
pretend that you have many things living on you but we all have well we all have
microscopic organisms that live on us in our eyelids and so it’s living in that
same boundary layer and plants have it all animals have it at least all
terrestrial animals and that is the origin I presume there may be
meteorologists will tell me I’m wrong and I would like to know I presume
that’s the origin of the windchill factor I mean have you ever thought why
does it get colder when the wind blows even when the wind is the same
temperature as the air around you why shouldn’t in fact it should get warm up
just from molecular movement that’s what I learned in in physics you get colder
because the moist warm boundary layer is blown away from you and for the first
time you were exposed to the real atmosphere there it is and you don’t
have a chance for that protective boundary that’s that’s a suggestion that
might be wrong but the boundary layer is there and it’s there for all organisms
it means that any parasites that live on organic ectoparasites live on organisms
are living in that boundary layer and that is a condition for the evolution of
those ectoparasites because if they get any bigger
even though before they were the boundary layer if they get bigger
they’ll stick out of the boundary layer and they’ll be out in the in the
atmosphere there somewhere so organisms are creating that own
little world around themselves metabolically and that means that if
you’re going to do any interesting work on the environmental relations between
organisms and the physiology of organisms and the outside world you have
to take the measurements at a microscopic level you have to do what I
call microclimatic measurements you have to go out there with sensors and put
them under the leaves of growing plants on top of the leaves of growing plants
there’s a different co2 concentration on both sides there’s a different moisture
concentration there’s different light clearly you have to measure the the all
the variables in a field of corn at different heights above the soil it
matters whether the plants have lots of leaves or few leaves and so on there was
a industry and agricultural research for some time called plant engineering in
which an attempt was made to make plants more efficient in their fixation of
carbon dioxide and light by engineering the shape of the of the leaves and the
number of leaves and the height of the leaves and and so on and they did that
they were able to make plants that fit what they predicted ought to be more
efficient users of the co2 in the light the trouble is when they made the plants
different then all the variables changed because now the co2 concentration
changed the light incidence change and had to redesign the plants and they were
constantly chasing a moving moving problem because it’s the plant that
determines how much co2 there is there it’s the plant that determines how much
light gets through from here to there and so on so it’s very important to
understand that organisms by their shape and morphology shape and and physiology
and metabolic rates create a world around themselves and all and and taking
them weather measurements at the top of the building tell you nothing and indeed
Canadians know that the Canadian Department of Agriculture puts out vast
tables of microclimatic measurements made at various Heights in cornfields I
think the Americans have not yet become hip to that notion of thing but they
should okay so organisms then create a world
around themselves whether it’s a building a nest or just the boundary
layer or just choosing where to go and I’ll tell you one more example so you
understand the general idea many years ago a student of man named
competent Rick along on student of Drosophila decided to ask why it is that
there are some populations of a certain species of Drosophila that were able to
live in Zurich for other dry environments like out there in the
desert whereas others required a moisture environment so he brought the
flies in from nature and he built a gradient and he let the Flies choose
where they would move in the gradient and that it was a gradient of moisture
so he put the Flies in the middle and in some flies they went to the left and
someone to the left and so went to the right and what he expected to see was
that the Flies that came from the Zurich and firemen were more comfortable where
it’s dry and they would move to the dry part and the Flies that came from the
medic environment more comfortable in the wet and they would move to wet part
but exactly the opposite happened the flies that came from the more Zurich
environments moved more quickly to the moist part of the gradient and it took
them about 10 seconds to realize that of course what a call Zurich and Messick
environments are made in weather stations the real issue is what the
microclimate and micro environment of these little fruit flies is and they
weren’t there were no flies living in Zurich environments they were all living
in medic environments in order to live in and what we call to Zurich
environment you have to be very good at finding the moist micro habitats and if
you’re very good at finding of them then you survive otherwise you’re exposed to
the nasty dry desert and you die and fruit flies die very quickly because the
waxes in their cuticle melt and all the moisture comes out and they’re dead in
no time so the organisms then seek out actively by
behavioral phenomenon those micro climates and micro environments in which
they can survive better and in that sense then they are determining their
own environment because the environment of those flies is not out in the middle
of the sand in the middle of the desert it’s in little cracks and crevices okay
so that’s how organisms create their own environment but they don’t just create
their own environment they also at every moment are both destroying and creating
the environment producing and destroying every act of consumption is an act of
production and every act of production is an act of consumption at every
instant we are consuming oxygen and giving out co2 right we are changing the
world but it is known Lipa were doing that you know every aerobic organism in
the world is taking up oxygen and turning it into carbon dioxide and the
world is changing as a consequence but fortunately there are some organisms
that are green and take the carbon dioxide part of the time and turn it
back into oxygen hood again in fact as you know all the free oxygen in the
world was put there by plants before there were plants oxygen is very
reactive and and and free oxygen is not a stable part of the atmosphere there
was a large amount of carbon dioxide and virtually no oxygen plants made it’ll
mostly oxygen eighteen percent oxygen and reduced the carbon dioxide to four
or what is it four one hundreds of one percent or whatever it is what happened
to all the carbon dioxide that used to be there it was deposited in limestone
and in fossil fuels by living organisms all that limestone used to be free
carbon dioxide so the world as a whole is changed by the organisms but it’s not
just the world as a whole it’s changed by it the organisms change their very
own world in which they’re living in very important ways every species not
just the human species but every species is in the process of destroying its own
environment every species breathes in something it needs and exhale something
it doesn’t want every species leaves fecal matter every species is in the
process of fete of fouling its own nest at the same time all kinds of species I
intend to say every one but I can’t give examples for every one or in the process
of changing the world around them in their environment in a way that’s
advantageous to them not just human beings a plants I mean you’ve been
talking about dumb organism how about plants you know they don’t think about
anything they don’t move much but they create by their metabolic activities a
world not just above ground but below ground which is hospitable to their own
growth plants put out roots the roots change the physical structure of the
soil in ways that are advantageous for taking up moisture there are things
called humic acids which are excreted through the roots of vascular plants
those humic acids change the chemical composition soil promoting the growth of
mycorrhizae fungi which then in an association with the plant root hairs
nourish the plants plants are out there farming for themselves so to speak and
they’re doing that all time and and the change in root in both chemical and
physical structure of the soil created by plants is has a powerful effect so
organisms are both creating and destroying their own environment at all
times sometimes that creation destruction
takes very interesting and important forms for example it is not human beings
who invented the struggle between generations in new england where we come
from it used to be that there were vast pine forests along came the lumber
companies and the paper companies in thought ah we’ve got it made
they bought huge acreages of these pine forest white pine and cut it down for
paper and lumber expecting of course that if they waited long enough back
would come the pines but they don’t when you cut pine trees in northern New
England or middle Norland what comes in instead are hardwoods and every time he
cut a pine and Grove in come hardwoods Pines don’t come in what was discovered
by many years of research and historical investigation was that pine trees are a
middle stage of succession of the forests in New England that first you
have and that Pines come in first into abandoned fields now in their nineteen
in 1840 at least the part of it in Vermont where we live our town had more
people in 1840 than it’s had since and then when the western lands were opened
everybody picked up and said I’m not going to farm this stony ground anymore
and they all went west to Pennsylvania Ohio and some were deep soils abandoning
their farms many farms are also abandoned in the depression when you
abandon a field in that region the first things that come in are scrubby herbs
and so on then li’l largely what are called old field pine single pines that
come in and pretty soon the pines grow up and you get a pine grove but pine
seedlings cannot grow under the shadow of their own parents the pine seedlings
that that that start to grow under the shadow of these pines are stunted and
don’t make it at the same time there are hardwoods being blown in from other
places or brought in by animals and they have a somewhat better ability to grow
up the moment you cut the old pine trees those hardwood seedlings take over and
completely change the composition of the population into hardwoods and that has
been repeated experimentally and you can see it if you get in an airplane and fly
from Boston to Chicago look down you’ll see the stone walls marking the old
you’ll see the pines coming into them and then if you keep going you’ll see
older fields and if the pines are gone and the hardwoods have taken their place
pines are weeds I know you may not think of pines as we I’m talking with a white
pine and in eastern our weeds ie plants which can only grow in disturbed
habitats and which then change the nature of that disturbed habitat in such
a ways to be hostile to the next generation of their own species that’s
what a weed is a weed is a plant not not a plane that comes into cornfields
that’s that’s a special kind of weed weeds weedy plants or plants that come
or weedy animals for that matter come into disturbed habitats and then change
the nature of the habitat so they can’t replace themselves and make it available
to new forms and weeds are a classic example of how organisms make and remake
the environment sometimes in ways that are ultimately hostile to the next
generation so that’s a long-winded way but I think I have to go over and over
to convince you that it isn’t just people who are destroying and making
their own world it’s organisms in general at every
instant are making and destroying their own that’s the process of construction
the next thing that and I mean I can think of lots of stories Mort saw some
of you know he once said remember he said I met our cruel nasty and evil
you’ve been today every time you take a breath you make a flower happy and yeah
that’s the way you have to think about the interaction the next thing organisms
do is to do mathematics they can do both integration and differentiation let’s
say they do statistical averaging for example when a tree comes into flower
depends not on what the temperature is the day the tree comes into flower or
how much light there is what the tree is doing is accumulating degree days it’s
it’s integrate doing a time integral of the varying degree days until the total
number degree days gets big enough and then they flower all kinds of organisms
are time averaging a weird time averaging I’m time averaging and as you
are if you didn’t time average you couldn’t couldn’t live you eat just as
well in the winter time as you do in the summer time why is that because you have
mechanisms of storage of of nutrients and storage is a form of time averaging
of taking over so that for example oak trees store energy in the form of acorns
so that when those acorns fall on the ground and they’ve germinate the plant
can can come out that’s a stored average of soto
photosynthesis that occurred during the spring and summer when that tree was
producing the acorns which then next next year will sprout then squirrels
time averaged by gathering the acorns and and put them away for the winter
time so or animals will time average using the seeds of plants we time
average by using the time averaging of the potato plant potato tubers are a
cumulation of photosynthetic material which is then a storage of energy which
the which the potato can use to sprout we then take the potatoes and put them
in cellars or or storage facilities so we’re averaging over summer and winter
and then there’s a form of time averaging the people use that no other
organism can use and that’s money money is the time averaging device because you
don’t pay it on there are there are so called futures markets which even out
the price of potatoes over the year and they only fluctuate a little bit even
when they’re not being made by the potato plans so there
all kinds of mechanisms and then animals have yet another form of time averaging
when they eat and there’s plenty of food around they store fat and then that fat
is used during lean periods I mean we men have it in there greater omentum
women have it in other parts of their bodies but like all mammals they have
mechanisms for fat storage which carries them over lean and and fat periods bears
hibernate and use up the fat they have in them and so so so that time
integration is a very very common feature of organisms tubers fat cultural
things like the potlatch of the North Western Indians and so our all-time
averaging devices for averaging out the good and the bad times organisms also do
mathematical differentiation that assay organisms will respond in important ways
to changes in the rates of things if not to the rates themselves the most famous
example is of the water flea Daphnia which is sometimes sexual and sometimes
asexual Daphnia reproduce asexually by by parthenogenesis whether there’s a lot
of food or a little food whether there’s a lot of oxygen or a little oxygen
whether the temperatures higher temperature is low until a change occurs
in the temperature or food or oxygen so it goes from high to low or low to high
rapidly or rapidly a little bit of oxygen to a lot of oxygen or vice-versa
and when that rapid change occurs that’s a signal for the organism to be sexual
and they then produce males and the males mate with the females and I can
give you a long adaptive story about why that’s true but I won’t bother this is
simply evidence of the fact that organisms can change their life history
patterns in response to rates of change in the environment not just in the
levels of what’s out there so organisms have they do statistics and they do
mathematics finally let me say that organisms transduce signals from the outside world
in two entirely different signals which are not don’t resemble the signals that
come in the hot air that is accumulating in this room as a consequence both of my
speech and the metabolism that you’re all engaged in which is increasing the
temperature in here well there may be air conditioning on the would increase
in temperature is not felt by your livers as an increase in the mean free
path of molecules you know it doesn’t get hotter in you as it gets hotter
outside that signal which is a signal of molecular striking of your of your outer
skin and so on is converted by your metabolism into changes in the levels of
various chemicals in your body including hormones and so on because you are
homeostatic organisms who have those internal chemical means to keep your
body temperature constant inside despite the change in temperature outside and
that’s can only be done because the nature of the physical signal which is
an increase in the mean free path of the air molecules the temperature is being
transduced into a change in the concentration of
chemicals and that occurs constantly look when we used to go out into the
desert to collect flies we’d occasionally come across a sidewinder I
don’t know if any of you ever come across a sidewinder but it’s not a
pleasant experience when you come across a sidewinder the photons which have
impinged on your retinas and the the rarer factions of the air that have
impinged on your eardrums are converted instantly or almost instantly into a
chemical change inside of you name is the production of vast amounts of
adrenaline notice please if that species specific because I assume I don’t know
of course but I assume that when one Sidewinder sees another one
somewhat different chemical reaction occurs especially if there are opposite
sex so that is specific to your genotype as a species
so transduction of signals is another part of the life activity of organisms
which changes the immediate environment of the organism at least as it impinges
on the organism internally and you have an internal environment as an external
one so let me sum up all those features by saying that the best metaphor for the
relationship between organism and environment is one in which the organism
constructs an environment by its metabolic activities by its behavior by
its shape and so on and every species has its own environment and indeed since
organisms differ one from another within a species each one of you has a somewhat
different environment than each other one of you and you say well okay that
may be true but look how about gravity I mean we didn’t invent the law of gravity
well we did invent the law of gravity but we didn’t create gravitation you
can’t get away from gravity gravity is part of the environment of every
organism well not quite right if you are a bacterium you barely know gravity
especially if you’re in a liquid medium I mean a sedimentation rate of bacteria
and liquid medium is pretty slow gravity because it’s inversely proportional to
the square of the distance and especially because it depends on the
mass barely effects organisms like bacteria
it’s our genes that make us subject to gravity because we’re big in size if we
were as little as bacteria I wouldn’t bother on the other hand there are
forces that are very important in the life of any individual bacterium which
we don’t perceive that’s a when I move my arms it doesn’t affect you because
gravity falls off so rapidly also I am not knocked back and forth on this stage
by the bounding of molecules by Brownian movement
but bacterial cells are if you look at bacterial cells in a liquid culture
they’re being moved around like this because they’re small enough that the
Brownian motion affects them so whether or not a universal force and Brownian
motion is universal gravity is universal but one of those forces are effective in
the life of an organism depends among other things on the size of the organism
but what is influential on the size of the organism well in the big sense again
it’s your genes I mean the difference between me and bacteria is largely in my
genes and its genes so we come to the very curious sort of counter proposition
that all the genes don’t make the organism the environment which the
organism exists which is important in the determination of what the organism
looks like is in turn made by the genes that is to say what you have and here’s
the sort of the bottom line is a kind of Co determination of organism and
environment in which both of them are both causes and effects now this is
something that any physics student knows perfectly well the world is full of
situations in which the dynamics of the situation are if I can put it in
childish mathematical terms there’s a pair of coupled differential equations
the rate of change of X with time depends both on the state of X in the
state of Y and the rate of change of Y in time depends on the state of X in the
state of Y and you got to solve those equations simultaneously or you don’t
know what’s going to happen we have for too long has taken the rules of
evolution to be that the environment is autonomous and has its own processes the
rate of change of environment is a consequence of purely physical forces in
the external world the rate of change of organisms in evolution is a function of
the state of the organisms and the rate and the changes in environment but that
decouples the two the coupling is done by rewriting that to understand that the
rate of change of environment with time depends not only in the state
the external world but also on the state of the organism itself
which is creating and constructing that environment and so you have a pair of
coupled processes in which organism and environment co-evolved every organism is
constantly in the state of both causing and being caused by the evolution of its
own environment so among other things this as a practical meaning in the in
the politics of the world the slogan let’s not destroy the environment or
let’s keep the the environment is a senseless slogan because the environment
is changing all the time and there’s nothing you can do about it this is
nothing you can do about the fact that it’s changing what you hope is you can
do something about the direction that it changes you might have some influence on
making the environment change in a way that’s better for for whoever you want
it to be better for but you can’t stop the world and say I’m going to get off
the environment of every organism is evolving as the organisms evolve in
addition to the geotech tonic processes and so on that are going on I began
yesterday by talking about the history of evolutionary thought I want to leave
you with probably as good a time as any with one of the most important
evolutionary statements ever made made in the middle of the 18th century by one
of the incite french encyclopaedists Dennis de veau who in the in his perhaps
most famous book will have the dot on bear the the the dream of of Dalembert
who was a scientist and philosopher and I give it to first and French to show
off and then give it you an English person and they’ll have the done on bail
he says two songs two bus in Yakub the kookiest
everything changes everything passes it’s only two totality that remains I
think he was probably wrong about that as well
I don’t think the totality in any sense is going to remain but but this is the
right way to understand evolution that organisms and their environments
are inseparable and code defining and Co evolving and co-constructing clearly had no one interested so I’m
sorry you’re doing the call overproducing yes part of my talk is what happens when
different genetic types of Drosophila compete with each other so-called in a
tube of well-defined medium it turns out that if you count out the number of soft
legs into a well-defined medium on which yeast is growing the rate of survival of
those eggs to adulthood increases as you increase the number of eggs for a while
reaching a maximum at about in this particular experiment eight individuals
per vial and then starts a decrease again that is to say that the activities
of those the eggs of yourself oh by the way hatch into little maggots larvae
those maggots tunnel in the food and the process of tumbling in the food they’re
doing farming they’re creating surface area on which the yeast grows and the
consequence of that is that they for a while produce more than they consume and
the result is that you get an increase in survivorship broaden their activity
and then when you put too many in you begin to get a decrease in survivorship
the consequence of that kind of activity in of cassava is that if you do
experiments putting two kinds of resolve two different genetic types of
Drosophila in the food at the intermediate density which is the
optimal density for cassava both kinds survive equally well but at the lower
densities one kind survives much better than the other and at the highest
densities one kind survives much better than the other there but they’re equally
they do equally well when they’re farming as efficiently now another
consequence of that is and I think it’s an answer your question is if I do a
competition experiment of genotype egg and stenotype
B a will be be in this little experiment I then take B and try it against C B
beat C so a beats B
and BBC now every economist knows in this room that according to the rules of
utility theory if a beats b and b beat see a better beat see this is called
transitivity but when you do the experiment most of the time or much of
the time c beats a let us say that the outcome of a particular interaction
between two genetic types depends on the particular two genetic types and you
can’t predict what a will do against c until you try it and that’s because
there are multi-dimensional dimensions along which organisms interact so a
might be beat B because a is bigger than B B might be beat C because b is faster
at getting the food than C but C might be did beat a because C is smarter than
a I don’t mean B be smarter for a fruit fly but you get the point that that each
interaction has a unique biology because the organisms are creating a world each
one in its own way and the rates of that creation change and so the rule of
transitivity in utility theory doesn’t count in biology I mean those of you who
do economic utility Theory I don’t know that it applies to people either but I
have to leave that to you but we have by the way we do have
experiments with people in which an a person will choose a against B when
those are the only two opportunities will choose be against C when those in
only two opportunities but if you give them a and C counter-intuitively they’ll
treat C over a that’s bad news for economists and I don’t know what they do
about it but but that’s the rule for organisms it’s different strokes for
different folks and it’s because they’re creating their own environment and that
question was raised yesterday in the question period and I had hoped to have
more time to talk about that but because organisms are creating their own worlds
in different ways there’s no predictability of what a will do against
B and B against C and C against a we got to do the experiment
unfortunately look before you get away let me try my other mantra on you which
is comes out of this discussion and that is a difference between organisms and
other physical the organs of physical systems of course
13 organisms and other physical systems that people study is that most physical
systems that people study are either extremely large or extremely small and
generally they are home internally homogeneous to in a functional sense so
if you want to know about planets going around the Sun you don’t have to know
too much you have to know how how much their mass is and you know and how how
far they are from the Sun and a couple of things three or four things enough to
predict and if you’re talking about electrons or protons you don’t have to
you got to know how charming they are and a few other things like that but you
don’t have to know much to know what an organism is going to do requires a vast
amount of information because organisms have two properties which is very
inconvenient they are intermediate in size neither
big enough to make gravitation very important in their interactions with
other organisms nor small enough to behave like elementary particles their
intermediate in size and they are internally heterogeneous functionally
the consequence that an organism the living organism is the Nexus of a very
large number of weakly determining causal pathways and that makes it
extremely difficult to be able to predict what’s going to happen next when
you put two organisms together let me say Lane define finally on this point
what the difference is between being sick and being well is in my view a
normal or well organism is an organism whose life is the Nexus of a large
number of weakly defining interacting causal pathways a sick organism is
precisely an organism that is under the sway of a single determining causal
pathway you know I got a diseased liver or have a need a fix or something of the
sort no no I mean that’s what we mean by illness that your life is determined
deeply by one powerful force whereas the well individual is unconscious if I may
say of all those interacting forces because there now this makes extreme
difficulties for Experimental Biology because an experiment is precisely an
attempt to analyze a large number of weakly defining forces but holding
everything constant except one thing and tweaking that one thing strongly enough
to have an effect the problem is that if I first of all one of the problems
holding everything constant but when you hold everything else constant and make a
major perturbation in one how does that scale on to the normal situation of
everything changing and everything having small perturbations in genetics
we learned early that major mutations may often give you a very false notion
of how organisms are are actually operating because you’re making a big
change in something we’re ordinarily the control systems are dealing with very
small perturbations and that’s a serious problem for Experimental Biology and I
don’t have an answer for it because the analysis requires holding everything
else constant as much as you can and moving one thing but all of those who of
you who work on nonlinear interacting systems know that when you hold
everything else constant and make a big perturbation in one element that’s a
very poor predictor of what happens when everything is varying and you make small
perturbations I mean nonlinear large interacting systems are nasty that way what are using for example the depth at
which they swim by choosing if I use the word choosing I mean I don’t mean or
they think about it by by deciding if you like whether they go in schools or
singly by browsing on particular kinds of food it’s the it’s the organism
decides what to eat and in fact many organisms as you know have so called
search patterns which they switch depending on the abundance of things and
so something becomes the food of something when everybody decides that’s
a good thing to eat and a little later something else becomes the food so fish
living organism living in aquatic environments also how change look let me
give you the best example I can when I’ve actually observed myself if you
dive in the Barrier Reef in Australia in the Carl pools you will observe well
over a hundred species of fish living in this coral pool which is half as big as
this room completely surrounded by Carl with a sandy sandy floor and each fish
there is making a living in a different way out of this bunch of Carl some are
nibbling at the Carl you see the Carl being dropping down to the surface some
are taking only what sticks out of the surface
some are eating down here some are eating up there some are eating other
things which are floating around just in the way they eat and those behavioral
phenomenon in this fairly simple environment although it’s got a lot of
micro complex in it those different fish are doing things that are if I may allow
to be a genetic determinism dictated by their DNA so that’s my example from fish
in fact I was taught old fashioned ecology when I was a stew
that the chief important thing in the ocean was at what depth you were
determined what light reached you that determine what temperature there was and
blah blah I nobody believes that anymore I think I’m glad somebody was actually asked the
products because that’s a very word converted I see exist now there are the
there are the bird fauna of the chaparral in north america and
extraordinarily similar bored fauna made up of totally different species
unrelated species in the Mataram of chile so to say that organisms create
their own environments is not the same as saying that they well let me quote a
very famous political economist who said men I’m sorry about that men make their
own history but not as they choose let us say there are constraints there are
constraints at how you’re going to make a world and that has to be remade within
those constraints and I think the question for us has to be how to find
out what those constraints on the manufacturer of the environment is but
convergence certainly exists and that’s an indication that you don’t make your
own history as you choose there are ways it’s it’s like what I
talked about yesterday those big holes in the in the occupancy of the space of
organisms there are some parts of space that are prohibited there are other
parts of space that are easy to get to other parts of space that are hard to
get and that would be my answer to you it’s it’s a vacuous answer because does
have any concrete in it it might indicate some direction of research I
don’t know if that satisfies you well it’s important that it does I’m sorry I’m not quite sure I
understand the question could you say it again well I don’t think a hologram so I
mean that’s that’s a basic element of the interaction of molecules even at the
quantum level because we have different vibrational States and so on what
organisms have done however in their evolution is to modulate the effects of
randomness on their growth and development and let me give it one
specific example I talked about a lot of randomness in cells arising because of
the low concentration of molecules that are important 7 of this kind familiar
there’s one kind of molecule which is terribly important to a cell and which
is president one copy only at least in bacteria and that’s DNA now think about
what it would be like if at the division of a cell random parts of the DNA went
to two different cells I mean that would be death what has happened in the
evolution of molecular evolution is that precisely because DNA is president one
copy only I mean president two copies and OspA it’s one only in a bacterium an
extremely complex mechanism has evolved to guarantee that each offspring cell
gets one and only one copy that’s what the whole business about DNA replication
is all about otherwise we wouldn’t have double-stranded DNA
singles and at one time nobody in this room probably remembers that well some
of us may there was a theory before bacterial genetics was understood very
well that in fact bacteria is simply divided there their
genes sort of randomly and a lot of claim was made for that but but I think
it’s very important that that case though the greater the potential noise
the greater the selection pressure to create systems which damp the noise and
we can see that in a variety of ways some computer simulation work done by
Peter Gauss has shown has asked answered the following question why is it that
when you look at the molecular details of networks metabolic networks in cells
that you so often see not just redundancy but an awful lot of
redundancy let’s say somehow the control systems don’t depend just on one wiring
loop but there are many wiring loops all of which are doing the same job in
alternative ways so if you cut one you’d still get the same feedback if you cut
two you’d still get the same thing so why are they so sloppy or profligate and
what he found was by his simulations that even if you cut one or cut two or
got rid of them the cell would still go through what it was going through but
the effective noise would be greater than what the reduplication and apparent
profligacy of excess duplication was doing was holding down the effective
noise and that’s one mechanism which cells can use to reduce noise effects
and that is to have alternative duplicate pathways of feedback control I went I guarantee to offend everybody

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