Imagine a world without Darwin. Imagine a
world in which Charles Darwin and Alfred Russel Wallace had not transformed our
understanding of living things. What . . . would become baffling and puzzling .
. . , in urgent need of explanation? The answer is: practically everything
about living things. . . .
-- HELENA CRONIN, The Ant and the Peacock,
(Cambridge University Press 1992
We celebrate Darwin because he had one of the
greatest ideas of all time. He isn’t just a founder of modern biology, but you
cannot imagine modern anthropology, infectious disease & public health,
economics, or even sociology with their insights from Darwin.
So what did Darwin really discover when he was
29 years old, fresh back from 5 years sailing around the world? It probably
isn't what you always thought.
It wasn't evolution per se. There had
been an active public discussion of biological coming-into-being since before
Darwin was born (his grandfather Erasmus even wrote poems on the subject).
It wasn't adaptations to fit the
environment, as the religious philosophers had already seized on that idea as
suggesting design from on high.
Nor was it "survival of the fittest."
That idea had been floated by Empedocles 2,500 years ago in ancient Greece, long
before Herbert Spencer, in the wake of Darwin, invented the phrase we now use.
It certainly wasn't the basic biological
and geological facts that Darwin discovered, although during his voyage around
the world, and after discovering natural selection, Darwin did add quite a bit
in the factual line.
What Darwin contributed was an idea, a
way of making various disconnected pieces of the overall puzzle fit together,
something like trying to solve a jigsaw puzzle without a picture for a model.
He imagined the picture.
It wasn't, however, the idea of descent
from a common ancestor. Diderot, Lamarck, and Erasmus Darwin had all speculated
on that subject two generations earlier. And there were trees of descent around
to serve as examples, given how by 1816 the linguists were claiming that most
European languages had descended from the same Indo-European root language.
By 1837 Darwin had concluded that nature
was always in the process of becoming something else, though again there had
been other attempts like Lamarck's along this line. Darwin just looked at the
biological facts in a different way than his predecessors and contemporaries,
not forcing them to fit the usual stories about how things had come about.
Fitting facts to an idea is a primary way in which progress is made in science,
but a fit in one aspect has often blinded scientists to more overarching
explanations.
But even that wasn't his main
contribution. Charles Darwin had an idea that supplied a mechanism, something
to turn the crank that transformed one thing into another. He solved the
2500-year-old conundrum of the philosophers about chance versus necessity,
randomness vs cause. He saw that it was a combination of the two, chance
providing minor variations and the environment causing some variants to do
better than the others. And that it operated over and over to slowly change one
species into a new one. People who don’t understand evolution very well still
use this old opposition of chance and necessity to play debaters games with a
lay audience, demonstrating their profound ignorance of how the combination of
chance and necessity can work wonders – or their profound cynicism in trying to
win points by confusing their audience.
BASICALLY, CHARLES DARWIN (in 1838 and,
independently, Alfred Russel Wallace in 1858) had a good idea about the process
of evolution, how one thing could turn into another without an intelligent
designer supervising. Out of all the variation thrown up with each generation
(even children of the same two parents can be quite unlike one another), some
variants fit the present environment better. And so, in conditions where only a
few offspring manage to reach adulthood (both Wallace and Darwin got that
insight from Malthus and his emphasis on biological overproduction), there is a
tendency for the environment to affect which variants get their genes into the
next generation.
Many are called, few are chosen by the
hidden hand of what Darwin labeled "natural selection." The name comes from the
contrast to animal breeding, so-called "artificial selection." It is, as Ernst
Mayr noted, an unfortunate term, as it suggests an agent doing the natural
selecting.
As Thomas Huxley said, when reading
Darwin's book manuscript before its publication in 1859, "How stupid not to have
thought of it before." Two and a half millennia of very smart philosophers
trying to solve the problem, and then the answer turns out to be so simple.
A few years later, Darwin realized that
he needed to add an "inheritance principle," to emphasize that the variations of
the next generation were preferentially done from the more successful of the
current generation (the individuals better suited to surviving the environment
or finding mates). This means, of course, that the new variations were not just
at random, but were centered around the currently-successful model.
In other words, they were little jumps
from a mobile starting place, variations on a theme, not big jumps where the
starting place becomes irrelevant because the jump carries so far. (Warning:
Except for the pros, half of the people who write about evolution, whether pro
or con, may be confused about this important short-distance randomness aspect.)
Many variations, of course, are not as
good as the parents - nature appears not to worry about this waste, to our
distress - but a few variants are even better than their parents. And so, with
passing generations, there is a chance for drift to occur towards the better
solutions to environmental and mate-finding challenges. Perfection you don't
get, but occasionally you do get something that, locally, could be called
"progress" - that ill-defined something that makes us so impressed by the
Darwinian process. Nature can be seen to pull itself up by its own bootstraps,
amidst a huge waste in variations that go nowhere.
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The six essentials turn the
crank.
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Speciation can occasionally
provide a ratchet to prevent
backsliding.
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Grand themes in evolution are iffy.
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Progress is only locally defined.
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Worse, evolution may not continuously emphasize a theme like
“intelligence.”
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Instead, one sees multiple-use structures paid for via one use,
but having free secondary uses.
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These sidesteps may provide the fast tracks to “intelligence” and
such.
Human evolution background and
what drives it
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Reciprocal altruism is a fancy name for doing
favors for friends.
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Beyond grooming, sharing has a long growth curve.
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You can double your payoffs by sharing
more things, with more people, over longer
periods of time, onwards and upwards
to volunteer fire departments and even
third-party peacekeeping forces.
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Even if you kill a big animal yourself, it’s too much to eat by
yourself.
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Better to give away most of it and count on reciprocity from others
tomorrow.
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Even chimps share meat, when they catch small monkeys or pigs. They
don’t share anything else with other adults, but they do share fresh meat.
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In prolonged sharing, there is the problem of freeloaders —
everyone loves a freebie, so you need some abstract mental categories for who
owes what to whom, so as to avoid or break off alliances that are unequal.
Who owes what to whom as a setup for language
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Abstract mental categories for giver, recipient, and value are just like
the other major way of understanding a long sentence about “Who did what to
whom” where you identify which actors go with which verbs, and so on to
understand the little play conveyed by the long sentence.
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Many aspects of meat-eating cannot be intensified. Besides ever more
sharing, another long growth curve is throwing.
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Twice as far, twice as fast, twice as accurate — they’re all good for an
additional payoff in terms of days per month when your family can eat
high-quality food in hard times.
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And no matter how good you are, getting better
has an additional payoff, even more immediate
than improved sharing.
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The parts of the frontal lobe involved with planning novel hand and arm
movements also work pretty well at planning mouth and face movements.
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They also have a lot of overlap with brain regions used during
language tasks.
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This is consistent with the notion that planning and structured language
may be sharing multipurpose facilities, something like a skateboard using a
curb cut paid for by “wheelchair uses.”
Mind’s Big Bang at 50kyr
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Creativity (difficult)
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Symbolic stuff
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“Consciousness”
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Language
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Planning in depth
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Add to all the qualifier,
“with structure.” [WHC]
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Syntax, those phrases and clauses (often
nested) that make long sentences possible.
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Planning that is multistage and contingent.
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Chain/web of logic that, when they all hang
together, we say “understood” or “explained.”
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Games with arbitrary, changeable rules (gambling, too)
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Music that goes beyond rhythm and melody to use multiple voices,
as in part singing and symphonies.
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Coherence-finding, as when we discover hidden patterns amidst
seeming chaos.
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Complex thought, as in figurative speech, house-of-cards
analogies, parables, and narrative frameworks.
Oliver Sacks’ description of an eleven-year-old deaf boy,
reared without sign language for his first ten years, nicely shows what mental
life is like, when lacking syntax:
Joseph saw, distinguished,
categorized, used; he had no problems with perceptual categorization or
generalization, but he could not, it seemed, go much beyond this, hold abstract
ideas in mind, reflect, play, plan. He seemed completely literal — unable to
juggle images or hypotheses or possibilities, unable to enter an imaginative or
figurative realm.... He seemed, like an animal, or an infant, to be stuck in the
present, to be confined to literal and immediate perception….
Similar cases also illustrate that any intrinsic aptitude
for language must be developed by exposure during early childhood. Joseph
didn't have the opportunity to observe syntax in operation during his critical
years of early childhood.
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As Desmond Morris once said, we prefer to think of ourselves as fallen
angels, not risen apes. At least, we hope, evolution is still improving us.
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Alas, biological evolution doesn’t perfect things, it just moves on to
new “products” with a different set of bugs. (Sound familiar? Imagine a beta
version of Windows 1.0, a big step up from earlier, but not yet ready for prime
time. We might be like that.)
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Even when we avoid hanging up from obsessions or crashing from epileptic
seizures, we stumble over numerous cognitive pitfalls.
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Once you also recognize that we’re recently risen apes, you
realize that there simply hasn’t been much time in which to evolve a less buggy
version 2.0.
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The faster you go (without shortening
reaction times), the more easily a
pothole can spin you out of control.
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When innovation operates in one area faster than related ones, when
one is nimble and the other ponderous, things can bend and break.
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Takes a half-century for politicians to peacefully create better
institutions like the EU and the € Euro.
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Took less than a decade to invent atomic bomb.
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Took about four years to get a billion web pages.
“We've arranged a global
civilization in which most crucial elements… profoundly depend on science and
technology. We have also arranged things so that almost no one understands
science and technology.
This is a prescription
for disaster. We might get away with it for a while, but sooner or later this
combustible mixture of ignorance and power is going to blow up in our faces.”
– Carl Sagan,
1996
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As Stewart Brand said, we may not be gods but it is as
if we were, in our impact on the world and our own evolution – so maybe
we'd better get good at the god business.
–
Get the bugs out of the beta version,
–
expand the time span over which responsibility is expected.
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Certainly it is juvenile to assume that someone else will clean up
after us. Or pick us up after we fall.
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