Design within Design



Lifeless particles talk themselves into evolving, scientists say

BY RONALD KOTULAK
Chicago TribuneCHICAGO -

The only really bad argument University of Chicago physics professor
Henry Frisch can remember his parents having was purely academic. The
question: If a lightning bolt struck a primitive soup of basic chemical
building blocks enough times, is there a chance it could eventually
make a baby?

Frisch's father, an MIT physicist immersed in the knowledge that
inanimate atoms combine to make living things said the probability was
vanishingly small, but it was not zero. Given enough chances, such an
event could conceivably arrange all the necessary atoms in the right
order to produce an infant.

His mother, a Harvard biologist steeped in the choreography of living
cells, said that was utter nonsense. Life evolved slowly from the very
simplest forms to more complex ones. There isn't an extremely small
chance that lightning striking a concoction of chemicals, even an
infinite number of times, could produce a baby. There was no chance.

"They were sailing along and they ran onto a rock that they couldn't
deal with," Frisch said.
Although Frisch didn't take either parent's side, he now finds himself
drawn into an offshoot of the lightning-bolt question: How could
something as complex as intelligence and consciousness evolve from the
inorganic, elementary particles of the early universe? And is
intelligence limited to humans and some animals, or do plants and even
inanimate objects possess it?

The scientists raising these questions are part of a fascinating new
field called emergent properties, which someday may reveal how
complexity in nature ultimately crosses a threshold to produce
intelligence and self-awareness.

Their research goes to the heart of a pivotal question in evolution,
one that has become a hot-button political issue: Why is it that things
that are very large and very complicated, and have many, many pieces to
them, have structure and order?
For advocates of "intelligent design," life seems too complex to have
just happened. Some supernatural force had to guide it.

But to emergent-properties scientists, it is clear that all things from
the very beginning - atoms, molecules and so on, up to living organisms
- do their own "thinking" without any outside help. They communicate,
process information and form new unions, acquiring capacities that are
unpredictable and greater than the sum of their parts.
Evolution, rather than being driven by competition among individual
organisms, is propelled forward into more complicated organisms by
symbiosis and cooperation among cells. Carbon atoms, for example, can
be thought of as "talking" to each other, exchanging information on how
to hold hands to create a diamond crystal.

It's a concept that's shattering a long-standing assumption - that the
behavior of atoms and of all life forms, except for human, is basically
preprogrammed, preordained and reflexive.
"All of life displays emergent properties," says Utah State University
plant biologist Keith Mott. "Even a lot of things that are not life
display emergent properties. It means that when you get a bunch of
things together they do something that's completely different from what
you would expect from all of the individual components."

As information is concentrated, it has the capacity to move around, be
shared or seemingly amplify itself by providing a model for
less-organized neighboring systems, explains Cornell University
physicist Paul Ginsparg. "Once atoms form we can see how they
communicate to form molecules and eventually how genes communicate to
orchestrate life processes. It seems to me that information processing
is possibly the thread that ties together complexity and the richness
of the universe."

The concepts that underlie the field of emergent properties are rooted
in the explosive development of the early universe. The Big Bang,
researchers agree, left behind oceans of elementary particles with both
positive and negative electrical charges. The oppositely charged
particles attracted each other, forming hydrogen, the simplest atom.
Gravity drew the hydrogen atoms into denser and denser clumps until the
pressure was sufficient to begin crushing them together, forming helium
and releasing enough energy to ignite the fusion furnace that becomes a
star. This process continued as new stars aged, creating heavier
elements as smaller atoms were fused together to form bigger ones.
Finally, when the stars reached the end of their lives and exploded,
they blasted into space both the light and heavy elements, seeding the
universe with the building blocks of life.

These particles interact, pushing and pulling each other, constantly
throwing bits of information back and forth - their way of "talking."
Electrons whiz around protons and the atoms they form are forever
chatting with nearby atoms, joining into molecules, whose chemical
reactions created the precursors of bacteria, plants and other
organisms.
Finding out how all that happens, how life emerges from the interplay
of inanimate matter, is the goal of a new $5 million grant from the
National Science Foundation. Its ambitious aim is to duplicate the
steps by which electrons, protons and all the other atoms and molecules
form sets of chemical reactions that set the stage for life itself.

Among those whose work is funded by the grant are three University of
Illinois scientists: physicist Nigel Goldenfeld, who studies snowflake
formation in his pursuit of biological complexity; microbiologist Carl
Woese, who has unveiled new phases of evolution; and chemist Zaida
Luthey-Schulten, an expert in determining the molecular pathways needed
for early metabolic activity.

They are, essentially, trying to create life in a test tube.

"All of these particles are inanimate," says Goldenfeld of the early
universe, "but their dynamics are such that they form self-reproducing
chemical reactions that feed on each other and the environment. There's
a gradual buildup of complexity as one stage creates elements that are
then used to form the next stage.

"Although people have understood that process in a general way, we're
trying to understand it in a very specific way."

For Woese, the opportunity to try his hand at creating life is a dream
come true. A deep thinker who likes to cut through science's Gordian
knots, he bears the academic scars from repeatedly upsetting biology's
apple cart, and in the process bringing evolution into sharper focus.

In 1977, his brilliant analysis of the genetic composition of cells
revealed a third form of life, after bacteria and plants and animals:
the archea. They joined bacteria, whose genes are free floating in
cells, and plants and animals, whose genes are packaged in a nucleus.
Archea's genes are arranged in a way that lies somewhere between the
system used by bacteria and animals.

Classical biologists were miffed at Woese's third life form, believing,
as did Darwin, that the "tree of life" had only two main branches.
Archea, they insisted, are not a separate branch but members of the
bacteria family. How could an unknown upstart whose background was
biophysics overturn a tenet of biology that had stood for nearly 150
years? One Nobel Laureate warned a colleague of Woese's to stop working
with him if he wanted to salvage his own career.

As technology improved and it became easier to trace the evolutionary
history of life in genes, Woese's finding was finally accepted a decade
later, and his three-branch tree of life is standard in biology texts.

Woese next went after a big stumbling block in classical evolution.
Darwin's doctrine postulated that all living things eventually could be
traced back to a single founding cell. But the odds against that
happening are astronomically large. It would require all the building
blocks of life to come together in one place at the same time to form
the first founding parent.
Instead, Woese announced in 2002 that life did not start just once, as
had long been taught, but possibly millions of times. It was relatively
simple for raw chemicals, he said, to do what they do best -
communicate and form bonds - and build the first primitive genes. These
early organisms readily swapped genes among themselves, evolving more
efficient survival skills in the exchange. Most of the early life forms
consolidated or died off as three strains became dominant, he said,
founding the three domains of life.

This time, recognition of his work was swift. In 2003 the Royal Swedish
Academy of Sciences embraced the "Woesian revolution" by awarding him
the $500,000 Crafoord Prize, which is given for scientific research not
covered by the Nobel Prize.

His elevated stature hasn't changed Woese's work habits. He still sits
in an old swivel chair, puts his feet up on a cluttered desk and with a
computer keyboard on his lap lets his mind travel back in time more
than 3.5 billion years to try to envision how life on Earth first
started. The microbial world, he believes, holds the key to the genetic
history of human evolution.
Biologists have long thought that the life of a cell depends on a
two-step process: a source of energy and the molecules that take that
energy and use it to perform their life-giving functions. But Woese
thinks there is a crucial third step - organization. Things have a
preferred way of getting together and that sets the course for
evolution.

"Organization is not an arbitrary random ordering of things," he says.
"Organization is something that evolves from within. It is the nature
of the universe to organize with the passage of time."

And the laws of physics regulate that organization, he says. "Physics
has changed. Physics is now talking far more about organization of our
complex dynamic systems."
Woese made a discovery years ago that is now recognized as the possible
missing link between physics and biology. He showed that long before
amino acids became the building blocks of proteins, they had a special
property, preferring either to associate with water molecules or be
repelled by them, kind of like the 0's and 1's of computer code.

By communicating their preference, Woese and his colleagues believe,
amino acids may have set about organizing how nucleic acids, the
chemicals of genes, pair up with individual amino acids to knit them
together into proteins. This dependence between amino acids and nucleic
acids ultimately evolved into the universal genetic code of all living
things.

"Evolution is the fundamental base of biology," he insists. "It's not
that biology gives rise to just this incidental tinkering around called
evolution. It is that evolution gives rise to biology."
Goldenfeld calls Woese's insight the turning point on the road to life.
"This property that Carl measured is, in biology, like a relic of the
Big Bang. It seems to be something that relates to very early
properties of living matter, of the amino acids themselves before they
became deeply involved in the molecules of life."

Evolution comes in two forms, Woese says. The first is the kind that he
and his colleagues talk about, the natural inclination of the universe
to organize into more complex structures, from atoms to living
organisms. If the universe started over again, according to this line
of thinking, it would have some interesting differences, but it would
still end up very similar to the one we have now, complete with
single-celled organisms, plants and animals.
The second is the kind of evolution Darwin described from his
observations of the variations in species caused by environmental
pressures. So now we have Woesian evolution driven by the free exchange
of genes among the first primitive cells, followed by the random
mutation of genes that Darwinian evolution showed bestows better
survival skills on organisms.

Norman Pace, professor of molecular, cellular and developmental biology
at the University of Colorado, Boulder, says that the condemnation that
Woese's ideas initially aroused evoked the ostracism Copernicus faced
when he challenged existing dogma that the sun revolves around the
Earth.

"It wasn't patently obvious to people in Copernicus' time that the
Earth traveled around the sun, and in Woese's case they weren't
prepared to think about the microbiological and deep evolutionary stuff
he came up with," Pace says. "Woese has done more for biology than
anyone since Darwin. What Darwin provided was mechanism, natural
selection. What Woese gave us was evolution's map - here's what
happened."

The University of Chicago's James Shapiro, a pioneer of emergent
properties, faced similar skepticism when he first published his
insights about cellular communication 17 years ago to an incredulous
scientific community. In studying the behavior of bacteria he found
that, although they consist of single cells, they do not behave like
loners. They act together, just like an animal or any other
multicellular organism.

His colleagues found this hard to swallow. "It wasn't well-received,"
he recalls. "I later learned that the people who study higher organisms
didn't want bacteria to be able to do things higher organisms could
do."

But now it's widely accepted that bacterial colonies of many parts can
act as whole organisms. How they communicate and cooperate in large
numbers has become the basis for studying how bacteria maintain the
Earth as a livable planet. Because they make up the vast majority of
living organisms, bacteria and archea drive biology's energy cycle, and
they balance the atmosphere's oxygen and carbon dioxide content, among
other things.

The communication among bacteria is similar to how our cells talk to
each other. Human cells chat on a much more sophisticated level, doing
such things as warding off cancer and repairing cellular damage. The
chatter begins at conception when a fertilized egg starts dividing and
daughter cells busily inform their neighbors whether they are headed
off to become a brain, liver or toenail, so that they all don't try to
do the same thing.

"What's going on in biology, and is really very major, is we're
understanding how really spectacular cells are at figuring things out,
processing information, analyzing complicated situations and making
good decisions about them," Shapiro says. "The research agenda, at
least for the beginning of the 21st Century, is focusing on cells and
organisms as very sophisticated and powerful processors of
information."

Others have shown how various organisms have evolved different ways to
exchange this information. Ants, for example, communicate by chemical
"words" called pheromones, as Harvard's E. O. Wilson discovered,
leading him to develop the scientific discipline called sociobiology.

"The interesting point to be made is that different organisms and
different cells use different modalities to communicate," Wilson says.
"Humans are in a very small select group that use AV, audiovisual
communication. Ants belong to the vast majority of organisms that use
chemical pheromones, smells and tastes as their signal."

Organisms evolve these signals when it becomes advantageous to form
groups that improve survival. "The group is better than the individual
organism in competition for food, space and breeding," notes Wilson.

When Wilson expanded his theory to say that humans have social
instincts that have a genetic basis, an irate scientist dumped a
pitcher of ice water on his head at a meeting in 1978. The water-pourer
objected on grounds that the brain was a blank slate and that whatever
people do is learned. Since then science has come to terms with the
joint roles that genes and learning play in behavior.

A key issue raised by the study of emergent properties is the nature of
intelligence and consciousness, and whether bacteria or even diamonds
can be said to think. Some scientists say this kind of communication
is, indeed, a basic form of thinking. Others vehemently disagree.
Intelligence, defined as the capacity to acquire and apply knowledge,
is something only humans and maybe some animals possess, they argue.

"When two atoms start forming a crystal lattice, that is information
transfer," says Hans Bohner, a University of Illinois professor of
plant biology. "Some people would say a crystal has some intelligence,
a salt crystal or a diamond, because the atoms are organized in a
certain way. But I do not call that intelligence. It is intrinsic in
the quality of the atoms."
While many scientists may be hesitant to give a diamond the benefit of
thought, they are not so sure anymore about non-human organisms such as
plants.

Plants process information and act on it, so they have a form of
intelligence, says plant scientist Anthony Trewavas of the University
of Edinburgh, Scotland, who has spent 40 years studying plant
communication. They have self-recognition in the sense that they know
the difference between another plant's roots and theirs. And they move
and change shape, ever so slowly, to optimize exposure to the sun,
water and nutrients.

"Part of the problem when I talk about plant intelligence is that
people say, 'Oh, rubbish. They don't have a brain.' OK, they don't have
a brain, but you don't need a brain for intelligence," he says. "What
you actually need is an operating network of cells. If that network has
a way of controlling the flow of information and manipulating it, in
other words problem-solving, it is therefore regarded as intelligent."

Plants, for instance, can predict future shade from neighboring plants
by sensing their infrared emissions, and undertaking maneuvers to move
out of the way or to change their leaf structure so as to optimize the
area for collecting sunlight.

Once considered fringe science, plant intelligence is being taken more
seriously. Last May, an international group of scientists met in
Florence, Italy, for the first Plant Neurobiology Meeting. A second one
is scheduled for next spring in China.

Trewavas believes that brains evolved in animals, and not plants,
because of the predator-prey relationship in animals.

Plants have no need for quick mobility because they depend on the sun,
soil and water for sustenance. But the first predatory organisms had to
get smart to capture prey, and the prey needed to get smarter to
escape. This resulted in a race to develop specialized cells to process
information rapidly.

"You get this positive feedback system in which as predators become
faster, prey has to become faster or it doesn't survive," Trewavas
says. "You evolve even more nervous tissue to do it so you get up to
organisms that now move extremely fast, at the speed we are familiar
with ... Eventually the brains continued to evolve until you end up
with this complex structure with large numbers of emergent properties
coming out that you cannot predict from the behavior of a few simple
neurons - consciousness, for example, speech and things like that."
Giulio Tononi, a neuroscientist at the University of Wisconsin, says
consciousness may, in fact, result when lots of information is shared
at once. At the age of 16 in Italy, he decided that understanding
consciousness was the greatest puzzle in science and he wanted to solve
it. Now he believes the key may be understanding why consciousness
fades when we fall asleep.

Consciousness, his theory holds, emerges when a system integrates
information, such as when the different parts of the brain talk to each
other. As sleep sets in, those parts stop talking among themselves,
thereby dissolving the state of consciousness that emerged from that
communication network.

Scientists used to think that consciousness vanishes during
non-dreaming sleep because the brain rests and stops working.
Researchers showed that was wrong when they discovered that during
slumber the brain is still electrically and chemically as active as
during wakefulness.

Consciousness fades away not because the brain takes a nap, Tononi
speculated, but because its different parts stop communicating. To test
his prediction, he and his colleagues performed an ingenious
experiment: When they electrically stimulated an area of the awake
brain, that part quickly sent out conference calls to many other parts.
But in the sleeping, non-dreaming brain, stimulation produced no
conference calls. The area of the brain that was dialed up by the small
jolt of electricity sat on the message.

"It fit exactly the key prediction of the information-integration
theory," Tononi says. "The effect was very clear-cut."

Even though self-awareness, or consciousness, is the least understood
property of matter, humans prize it for giving us the ability to
quickly adapt to changing situations and thus a tremendous evolutionary
advantage.

But all life forms solve problems, and Tononi says we may be
small-minded in asserting that other organisms, or for that matter
inanimate things, do not experience a degree of consciousness.

"If you say that consciousness is a system's ability to integrate
information, then anything that's made up of interacting parts will
have a little amount of consciousness," he says. "Does a crystal have
consciousness? At one level I have to say yes, but at another level I'd
say it is so low that it's basically nothing. Animals will have it for
sure, apes, monkeys, cats and dogs."

Even single-cell organisms might be said to have consciousness. The
bacterium E. coli, for example, can tell when its DNA has been damaged
and turns on repair systems. It holds up cell division until all the
DNA is mended so that daughter cells will be healthy. It can then
"sense" when the repair is complete.

"Do you call that self-awareness? I don't know," Shapiro ponders. "You
can get into a long debate about that. But until we understand emergent
properties like that more thoroughly than we do, it's difficult for us
to deal with some of these large philosophical issues.
"There's a lot of surprises coming up in biology and it's precisely
this focus on information processing that is going to bring those
surprises to us."


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