Speculations on the Future of Human Evolution

ARCHAEOPTERYX LOOKS UP

by Frank Wilczek
The New York Academy of Sciences
Update - September/October 2006

Archaeopteryx could fly 
—but not very well. 

Human beings today 
can penetrate outside 
Earth’s airy envelope
—but not very well. 

Our minds 
can penetrate 
into realms of thought 
far beyond the domain 
they were evolved to inhabit
—but not very well.

It seems clear 
that the present form 
of humanity is, 
like archaeopteryx,
a transitional stage. 

What will come next? 

I don’t know, of course, 
but it’s an entertaining, inspiring
—and maybe important—
question to think about.

QUALITATIVE EVOLUTION BASED ON BIOLOGY

In the past, 
evolution has been based 
on natural selection. 

Its results are impressive. 

Yet from an engineering perspective, 
natural selection is both haphazard and crude
—haphazard because no meaningful goal is explicit; 
crude because it gathers feedback slowly and with much noise.

What we might call 
its “goal” is simply to keep going. 

Its “performance criterion” 
is production of fertile off spring: 
what Darwin called the struggle for existence. 

That “goal” is, of course, 
not a mindful goal,  nor is 
the “performance criterion” 
a performance criterion 
in the conventional sense, 
where we judge how well 
some concrete task 
has been accomplished. 

Yet natural selection,
by allowing information 
to flow from the environment
to the replicating unit—the genes—
results in effective adaptation
and creative response to opportunities. 

Famously, it leads to 
what seems to be inspired designs 
to achieve what appear (to us) to be concrete goals.

Viewed analytically, 
evolution’s design methods 
look terriblyinefficient. 

Feedback arrives once a generation, 
and its information content is just a few bits, 
to wit the number and genetic types 
of surviving offspring. 

Furthermore, 
that information content 
is dominated by unrelated noise, 
all the complex accidents that impact survival. 

By way of comparison, 
we routinely gather gigabytes 
of useful information every hour 
by using our eyes and brain 
to look out at the world. 

Evolution by natural selection 
produces impressive feats 
of creative engineering 
only because it plays out 
over very long spans of time (many generations)
on a very large stage (many individuals).

In the past, eugenics
—encouraging certain individuals 
to reproduce while discouraging others—
has been proposed as a path to human improvement. 

Even leaving moral issues aside, 
classical eugenics was doomed to failure. 

Selecting human parents 
on the basis of a few superficial characteristics 
is inherently crude and inefficient, 
with the same drawbacks as natural selection.

Only recently, 
with increased 
understanding of genetics,
development, and physiology 
at the molecular level, 
have truly powerful possibilities 
for directing evolution begun to arise.

Screening against 
catastrophic genetic diseases 
is widely practiced and accepted. 

But where are 
the boundaries between disease, 
substandard performance, 
and suboptimal performance?

Is deafness a disease? 
Is tone deafness? 
Is lack of perfect pitch? 

Any boundary is artificial, 
and arbitrary boundaries will be breached. 

What’s in store for the future? 

Some, if not all, parents
will seek to produce 
the best children they can, 
according to their own view of “best.” 

Parental (or governmental?) selection
will replace natural selection 
as an engine of human evolution.

Selection by genetic screening 
will be much more efficient.

What goals will parents pursue? 
(Note: I say will, not should.)

The most obvious goal 
is improved health, broadly defined
to include both physical vitality and longevity. 

The popularity 
of performance-enhancing drugs for athletes, 
of diets and food supplements, and, of course, 
our vast investment in medical research,
attest to our powerful drive toward that goal. 

In this area, the most fundamental issue is aging. 

After a long exile at the fringes of biology, 
the question of why we age, 
and what can be done to combat that process, 
has now firmly entered the realm of molecular investigation. 

Decisive progress 
may or may not come within a few years, 
but in a few decades it is likely, 
and in a century almost certain. 

Future humans will be healthier 
and live much longer than we do. 

They may be effectively immortal
—and they’ll all have perfect pitch.

A second goal is more powerful intelligence. 

It may not be obvious, 
especially if you pay attention 
to the American political scene, 
but the evidence of nature 
is that there is intense pressure
toward the evolution of increased intelligence. 

In the six million years or so 
since protohumans 
separated from chimpanzees,
even bumbling natural selection 
has systematically upgraded our brains 
and enlarged our skulls, 
despite the steep costs 
of difficult childbirth 
and prolonged infancy. 

I suspect an important part 
of the pressure for intelligence 
comes from sexual selection: 
finding a mate is a complicated business, 
and women in particular tend to be choosy.

The salient facts here are: 
first, that it was possible 
to come so far so fast 
(on an evolutionary timescale!), 
and second, 
that the limiting factor 
is plausibly the mechanics of childbirth. 

Together, these facts suggest 
that tuning up production 
of bigger and better brains may be simple, 
once we find the tuning mechanism.

More generally, 
better understanding 
of the molecular mechanisms 
behind development and learning 
gives new hope for improving mental vitality, 
just as understanding molecular genetics 
and physiology does for physical vitality.

QUALITATIVE EVOLUTION BASED ON TECHNOLOGY

Biological evolution, 
whether based on natural 
or parental selection,
is intrinsically limited. 

Early design decisions, 
that may not be optimal, 
were locked in or forced 
by the physical nature
of Earth-based life. 

Some of those decisions 
can be revisited
through the addition 
of nonbiological enhancements 
(man-machine hybrids); 
others may require 
starting over from scratch.

The concept of a man-machine hybrid 
may sound exotic or even perverse, 
but the reality is commonplace. 

For example, humans
do not have an accurate time sense, 
or absolute place sense,
or the ability to communicate 
over long distances or extremely rapidly, 
or the ability to record sensory input accurately. 

To relieve these deficiencies, 
they have already become 
man-machine hybrids: 
by wearing a watch, 
using a GPS system, 
and carrying a cell phone, 
a Blackberry, and a digital camera. 
[Remember this was written in 2006]

Of these devices, 
only the watch 
was common ten years ago 
(and today’s watches
are more accurate and much cheaper). 

Many more capabilities,
and more seamless integration 
of man and machine, 
are on the horizon. 

For better or worse, 
much of the cutting-edge research
in this area is military.

In other cases, 
incremental addition of capability 
may not be feasible. 

To do justice to what is possible, 
radical breaks will be necessary. 

I’ll mention three such cases.

The vast bulk of the universe 
is extremely hostile to human physiology. 

We need air to breathe, 
water to drink, 
a narrow range of temperatures 
to support our biochemistry; 
our genetic material
is vulnerable to cosmic radiation; 
we do not thrive in a weightless environment. 

As a practical matter, 
our major ventures into space
will be by proxy. 

Our proxies will be 
either humans so modified
as to clearly constitute a different species; 
or, more likely, new species
we design from scratch, 
that will contain 
a large nonbiological component.

The fundamental design of human brains, 
based on ionic conduction and chemical signaling, 
is hopelessly slower and less compact 
than modern semiconductor microelectronics. 

Its competitive advantages, 
based on three-dimensionality, 
self-assembly, and fault tolerance, 
will fade as we learn how to incorporate
those ideas into engineering practice. 

Within a century, 
the most capable 
information processors 
will not be human brains,
but something quite different.

Recently, a new concept has emerged 
that could outstrip even these developments. 

Physicists have realized 
that quantum mechanics
offers qualitatively new possibilities 
for information processing,
and even for logic itself. 

At the moment, 
quantum computers
are purely a theoretical concept 
lacking a technological realization, 
but research in this area is intense, 
and the situation could change soon. 

Quantum minds
would be very powerful, 
but profoundly alien. 

We—and this “we” 
includes even highly trained, 
Nobel-Prize-winning physicists—
have a hard time 
understanding the subtleties 
of quantum mechanical entanglement; 
but exactly that phenomenon 
would be  the foundation 
of the thought processes 
of quantum minds!

WHERE DOES IT LEAD?

A famous paradox 
led Enrico Fermi to ask, 
with genuine puzzlement, 
“Where are they?”

Simple considerations 
strongly suggest 
that technological civilizations 
whose works are readily visible 
throughout our Galaxy 
(that is, given current 
or imminent observation technology) 
ought to be common. 

If they were, 
I’d base my speculations 
about future directions of evolution 
on case studies! 

But they aren’t. 

Like Sherlock Holmes’s dog 
that did not bark in the nighttime, 
the absence of such advanced 
technological civilizations 
speaks through silence.

Main-sequence stars 
like our Sun provide energy 
at a stable rate for several billions of years. 

There are billions of such stars in our Galaxy. 

Although our census of planets 
around other stars is still in its infancy, 
what we know already 
makes it highly probable 
that many millions of these stars host, 
within their so called habitable zones, 
Earth-like planets. 

These bodies meet 
the minimal requirements for life 
in something close to the form we know it, 
notably including the possibility of liquid water.

On Earth, the first emergence 
of a species capable of technological civilization 
took place about one hundred thousand years ago. 

We can argue about defining the precise time 
when technological civilization itself emerged. 

Was it with the beginning of agriculture, 
of written language, or of modern science? 

But whatever definition we choose, 
the number will be significantly less 
than one hundred thousand years.

In any case, 
for Fermi’s question 
the most relevant time 
is not ten thousand years, 
but closer to one hundred. 

This marks the period 
of technological “breakout,” 
when our civilization 
began to release energies and radiations 
on a scale that may be visible throughout our Galaxy. 

Exactly what that visibility requires 
is an interesting and complicated question, 
whose answer depends on the means 
available to hypothetical observers. 

We might already be visible 
to a sophisticated extraterrestrial intelligence 
through our radio broadcasts 
or our effects on the atmosphere. 

The precise answer 
hardly matters, however, 
if anything like the current trend
of technological growth continues. 

Whether we’re barely visible 
to sophisticated though distant observers today, 
or not quite, after another hundred years 
of technological expansion we’ll be easily visible.

A hundred years is less 
than a part in ten million 
of the billion-year span over which 
complex life has been evolving on Earth. 

The exact placement of breakout within 
the multibillion-year timescale of evolution 
depends on historical accidents.

With a different sequence 
of the impact events 
that lead to mass extinctions, 
or earlier occurrence 
of lucky symbioses
and chromosome doublings, 
Earth’s breakout might have occurred
one billion years ago, instead of one hundred.

The same considerations 
apply to those other Earth-like planets. 

Indeed, 
many such planets, 
orbiting older stars, 
came out of the starting gate 
billions of years before we did. 

Among the millions of experiments 
in evolution in our Galaxy, 
we should expect that many 
achieved breakout much earlier, 
and thus became visible long ago. 

So, where are they?

Several answers 
to that paradoxical question 
have been proposed.

Perhaps our simple estimate 
of the number of life-friendly planets 
is for some subtle reason wildly overoptimistic. 

Perhaps, 
even if life of some kind 
is widespread, 
technologically capable
species are extremely rare. 

Perhaps breakout technology 
quickly ends in catastrophic 
warfare or exhaustion of resources. 

There are uncertainties 
at every stage of the argument. 

Even so, like Fermi, I remain perplexed.

The preceding discussion 
suggests another sort of possibility:
they’re out there, but they’re hiding.

QUANTUM QUIET

If the ultimate information processing technology 
is deeply quantum-mechanical, it may not be energy-intensive. 

Excessive energy use brings heat in its wake, 
and heat is a deadly enemy of quantum coherence. 

More generally, 
quantum information processing
is extremely delicate, 
and easily spoiled 
by outside disturbances.

It is best done in the cold and the dark. 

Quantum minds might well 
be silent and isolated by necessity.

Silence and inner contemplation can also be a choice. 

The ultimate root of human drives 
remains what our selfish genes, 
in the struggle for existence, have imprinted. 

That root is apparent in many 
of our behavior’s most obvious priorities, 
which include fending off 
threats from a hostile environment, 
finding and attracting desirable mates, 
and caring for the young. 

Those priorities
involve active engagement 
with the external world. 

The products of deliberate 
biological or technological evolution, 
as opposed to natural selection, 
could have quite different motivations.

They might, for example, 
seek to optimize their state 
according to some mathematical criterion 
(their utility function).

Having found an optimum state, 
or several excellent ones, 
they could choose ever 
to relive selected moments of perfect bliss,
perfectly reconstructed. 

This was the temptation of Faust:

If I say to the moment:
“Stay now! You are so beautiful!”
Then round my soul the fetters throw,
Then to perdition let me go!

Humans were not built 
to treasure a Magic Moment, 
nor could they reproduce 
such a moment reliably and in detail. 

For our evolutionary successors, 
that Faustian temptation 
will be much more realistic.

______________________________

Frank Wilczek is the Herman Feshbach 
professor of physics at MIT.
He received the Nobel Prize in Physics in 2004 
for the discovery of asymptotic freedom 
in the theory of the strong interaction. 

He is the author, with Betsy Devine, 
of Longing for the Harmonies: Themes
and Variations from Modern Physics (W. W. Norton) 
and the recently published, Fantastic Realities (World Scientific), 


Illustrations that can be seen in:


 A cast of the Berlin specimen 
of Archaeopteryx lithographica
shows its avian features 
(wings, wishbone, feathers) 
and its theropod features
(tooth-filled head, lizardlike tail).


A model of Archaeopteryx
lithographica displays
its large wings, 
but its lack of a bony breastbone 
would have made it a weak flier.

Photos by Ballista.

Cover of the Voyager Golden Record,
launched into space in 1977
on two Voyager spacecraft. 
Its sounds and images were selected to
introduce Earth to extraterrestrials.

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