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Breaking the reproductive mould -

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A cyanobacterium and a fungus have become the unlikely subjects of an inter-kingdom porno movie. It
challenges our views on mating and gene transfer - Lynn Margulis explains how this links to
symbionts, the mitochondria in our own cells and that gene transfer between different organisms is
more common than most people think.

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Robyn Williams: Do you remember this voice?

Carl Sagan: You see, when I was growing up, I found science-fiction to be full of wonder,
exhilarating, exciting, a way to get into scientific thoughts that I wasn't ready for in textbooks,
say, when I was a kid.

Robyn Williams: Well, that was Carl Sagan, in his time the most famous scientist alive. His TV
series Cosmos has just had a re-run. Carl Sagan's first wife is now nearly as famous. Professor
Lynn Margulis has had big ideas like Gaia (which she pioneered with Jim Lovelock), like the
supremacy of the microbes, and like novel ways of reproduction involving the fusion of totally
different species, the last of which she brought to the British Festival of Science in Guildford,
showing a porno movie.

Lynn Margulis: Forbidden Fertilisation shows a fertile union, the crucial pornographic part, of
organisms of entirely different...not species, not genera, not families, not even phyla, different
kingdoms! It's a fertilisation between a photosynthetic cyanobacterium and a fungus. And it makes
an organism that is definitely visible with the naked eye. It's can be up to five
centimetres or something, but you can see it, it's a moss-size organism and it looks kind of like a
plant. It's called Geosiphon pyriformae. The film that I'm going to show is by Dieter Mollenhauer
and I cut only the pornographic part out of a much longer film.

Robyn Williams: Fertilisation is something that you ascribe, as you say, to mammals. You have sex
cells and they kind of blend, they cross over.

Lynn Margulis: They fuse, they merge.

Robyn Williams: Sure, they're matched, they've got all the details of the code of different
versions of genes. What you're talking about is totally different creatures. We're used to
different animals coming together, and plants, for instance the corals have dinoflagellates in
them, they've got sort of algae in them. What you're talking about is a fertilisation of completely
different organisms. How does that work?

Lynn Margulis: Well, this is a special and very clear example of what I consider the major mode of
evolutionary innovation, and that the sex example that we're so familiar with, a cell opens its
membrane, namely an egg, and a sperm enters and you end up with a completely integrated, new
individual, which is amazing when you think about it. This is just an extremely special, limited
but familiar example of a far larger and far more important phenomenon which alas is denied by

Now, what is that phenomenon? It's what you said; it's organisms extremely different from each
other making a new organism. And this little plant-like thing that we'll see in the film cannot be
made in any other way. It's not like sometimes it does it, just like babies are not made by
splitting adults in half. I mean, there are lots of organisms that do reproduce by splitting in

Robyn Williams: May I just ask you, you said the evolutionists deny it. How can they deny it if
it's before their very eyes?

Lynn Margulis: It's not before their eyes, that's why I have to come here and show it. That very
wonderful film made by the Mollenhauer team, for 20 years they've been working on it, is not
thought of in the context of evolution at all, it's thought of in the context of what they thought
was a kind of peculiar alga. It's a wonderful story...

Robyn Williams: But does it happen commonly in other creatures?

Lynn Margulis: Yes, it happens commonly in the fossil record in the history of life. And look at
this, when you have a mother and a father you have a baby that's extremely similar to the mother
and father in every regard, right? But when you have a fungus and a cyanobacterium, what comes out
is shockingly new. So this is the point. The more different the organisms are that enter, the more
momentous the conclusion. But we have a biology, especially in Oxford, England, that denies even
the existence...they call it cooperation. I never do. Cooperation's for basketball teams and for
banks. It is genome acquisition. It's actually Lamarckian.

Robyn Williams: Ah, Lamarckian, now there's a naughty word. Lamarck is coming back more and more in
this year of Darwin. But once they're fused, they are then viable as new organisms to carry on as

Lynn Margulis: Yes. Now, the point is in this particular example...I'm going to show two examples,
this one and photosynthetic snails. Everybody knows what snails are. Slugs, escargot, totally
photosynthetic, and there you have the same thing. The photosynthesiser is very dramatically green
and has chlorophyll and photosynthesises, and in fact these slugs turn red in the autumn, right now
they are turning red because chlorophyll is stopped being synthesised, and they need the
carotenoids and all these other pigments. So you see these animals which are hermaphrodites and
they mate and they form eggs, and you see them turning red like leaves. They really look so much
like a leaf that one of them was on the cover of Plant Physiology.

So here you've got very different organisms. You've got the photosynthetic component and then you
have the animal. And you have a green animal that lies on the beach in the sun. You have a very
new, dramatic step. Nature's making leaps, there is no random mutation there, there's very
obviously the algal form can photosynthesise and the animal does everything animals do. And so you
end up with a new green animal.

To pick these two examples, because in nature this is the only way you make this animal, and the
point is that in these cases you have modern cyclical formation of a symbiosis. In the fossil
history of life we have our mitochondria, which became permanently associated, so we don't watch
the mitochondria come in and form a new association.

Robyn Williams: Yes, could I just say that we've said many times on The Science Show that
mitochondria were outside creatures which came to visit, just like chloroplasts in many ways, you
know, and they're built into the system. We've got many, many in each cell. Now you proposed this
way back. How long did it take before people accepted that these built-in parts, essential parts of
our cells, came from outside and were independent organisms? How long did it take to accept that?

Lynn Margulis: I think it's such an amazing thing. Robyn, it took, I don't know, 25 years or
something for the mitochondria story to be taught as truth. But the story itself goes back to 1921
in Russia. Now the chloroplasts are green and so it's like the photosynthetic snail, you see the
greenness, it cannot be denied. You watch the animals lying in the sun and sunbathing.

So that chloroplast story took less time and was there in the 19th century when the chloroplasts
were first described. I am fighting now, I have this week been rejected; or I can't say rejected
yet, I'm going to fight, I might have to go to a court of law; about the origin of the cilia, the
waving hairs on animals' cells, the sperm tails, the sense organs...lots of people know about
cilia...anyway, those organelles came from free-living spirochetes. Not only do people not accept
that, people who don't know...this has been suggested in the literature since the 1920s
independently in more than one place and so on...people who don't know, don't like it. And I think
they don't like the idea that their sperm tails are coming from outside spirochetes.

Robyn Williams: The sheer number of micro-organisms that we live with, in fact there are probably
more micro-organisms than cells in your body and mine...

Lynn Margulis: There are more.

Robyn Williams: They are more, far more. And one thing I didn't know was the number of viruses in
sea water. What was that amazing figure?

Lynn Margulis: Well, I think my colleagues said it was ten million. But it's ten million per

Robyn Williams: So a tiny drop has got those zillions...

Lynn Margulis: Think about it, you know, you can pack a thousand viruses, depending on size, into
one bacterium. And you can pack a thousand bacteria into one cell because of the actual size. But
there's a huge difference, just like a virus is not a chemical, it's more than a chemical. Of
course it is made of chemicals. In the same way, a bacterium is not a virus. A bacterium can, in
principle, be fed and grow by itself and metabolise by itself and carry on 100% of the properties
of life. A virus can do none of that until it gets into a live organism, a cell of other kinds, you
know, bacterial or animal or what kind of cell.

So a bacterium is the unit of life, the minimal unit of life that shows all the properties of life.
And the whole world is made of communities of bacteria and they say...'they', the ones who control
evolution in England and elsewhere, Anglophone countries mostly...say there is no group selection,
when all there is, is group selection. And they say random mutation caused the eye. Well, there is
random mutation of course at some level in protein changes and so on. But when you gain a
photosynthetic entity by swallowing it and then...Joel Cohen at Rockefeller said, 'Well, it's a
genome at a swallow.'

You realise that everything's community, that we have some sort of hideous phobia against
community, and there's no 'tree of life', there's a net, a web, a tangled bank, but no tree of life
at all. And you realise that the fundamental principles of evolution are not being taught. I mean,
they're just not being taught.

Robyn Williams: And that's why you call yourself a Darwinist but not a neo-Darwinist.

Lynn Margulis: That's one of the reasons, yes. Darwin observed...and he observed lots of different
things and he was a superb observer, and he came up with the natural selection, which is one of the
components of an evolutionary system, but evolution is a system. And the fact that all the
potentially born or hatched or butted or produced organisms do not make it to the next generation,
do not succeed in leaving offspring to the next generation, that is natural selection and that is
certainly an intrinsic component of evolution, and that's Darwin's big contribution. But it is not
the source of innovation. The source of innovation (I told you I don't say 'cooperation', because
'cooperation' is not an appropriate word), it is merging and fusing and interacting and doing more
together than it was alone. It's basically metabolic and genetic interaction.

Robyn Williams: And many of these bugs which are in our body are in fact interacting with our own
DNA. That's how we get colds. But they leave traces which get passed on, right?

Lynn Margulis: This is the viral part. Frank Ryan, whom you probably haven't interviewed but whom
you should, Frank Ryan has convinced me over the last few years that the viruses, including the
reverse transcriptase type of virus that HIV virus is, those entities are integrating the
symbionts. So they are the transport system for the genes. They are not genes by themselves,
because they must act inside a living cell. So they're not alive by themselves, but they are
without which we wouldn't have evolution because we wouldn't have a transport system for the genes.
And so the viruses play an extremely important role in evolution. They are enormously abundant, as
we said. But they themselves are not the ancestors to anything or the live entities that we make
them out to be, and that's why you can't study the virus without studying the organism in which the
virus is doing its action.

Robyn Williams: The remarkable Lynn Margulis, Distinguished Professor from Amherst Massachusetts.
She's now Visiting Eastman Professor at Balliol College in Oxford. And she was speaking at the
British Science Festival in Guildford.


Lynn Margulis

Distinguished University Professor University of Massachusetts Amherst Massachusetts USA


Robyn Williams


David Fisher

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