The
Chapter 11 a
The National Museum of
Natural History, part of the Smithsonian Institute, faces the esplanade. The public space is dedicated to informing
and amusing the casual visitors. The
private space is dedicated to developing and maintaining the skills that keep
the public part honest. As at any great
museum, the goals immediately directed toward the public are to a degree in
tension. The numbers that came did not
always reflect the quality of the experience.
It is one thing to pass
several thousand visitors through the galleries and have them feeling good and
exclaiming, “Wasn’t that panda cute.” And the numbers admitted were to a degree in
inverse proportion to the length of time each stayed. It was a question of throughput or
turnover. The sooner one batch left
satisfied, the sooner another could be admitted to the vast but still limited
space. These numbers were easily
recorded and tracked, and so far as they went they reflected the popularity and
thus the success of the enterprise.
On the other hand there was a
lesser number who came and spent the day or days studying in more detail. They often left emotionally moved, even
troubled. And there was no feasible way
to keep track of them. Yet the
institution made every effort to accommodate and encourage them. It was no good trying to trouble
everyone. Life has enough of
trouble. So the process was like the
creation of complex music, weaving together the obvious with the subtle in the
same time and space.
“Right in one,” said
“For the
museum?”
“Yes. It’s experimental now. We used to have little signs beside the
displays explaining as much as we could in the space of a three by five card. So you would have some people strolling by
just looking, and the rest jockeying for a position where they could read the
card. Then of course after the wait they
would be disappointed with how little they had learned.
“Then we tried making very
big signs to explain more, so you could read any sign from anyplace in the
room. And we put more information into
it. But then the signs dwarfed the
displays, and people got stiff necks from staring up at them.
“So we brought in volunteer
docents, who would act as tour guides and give a little lecture. They could also answer questions. But still everybody got the same spiel, so
some would be listening, but most would be looking around because they were
either bored or it was over their heads.
“So next we started handing
out recorded tours, which is what we do now.
The recorder picks up signals to tell you where you are and give the
appropriate information. You can set the
sophistication level so as to hear a recording that is pitched where you like
it. It can describe the time and
conditions of a dig and where a fossil or specimen fits into the environment
and into the most recent theories, or it can say, ‘Really big fish.’
“So far, so good, but for
someone who is getting interested, when they go to a higher sophistication
level they hear the first information repeated again. We wind up frustrating just the people we
want to reach just when they begin to open their minds. Besides they take too much time fiddling with
the recorder itself.”
“So that’s like a museum
recorder,” said Hapgood.
“Sure, try it on.”
Hapgood put the contraption on his head, and sure enough he
could see the room still, but superimposed was text describing the office. In fact, as he turned his head, the labels on
the desk, the windows, a cabinet of African objects and the door stayed with
their counterparts. There was a target
in the scene that moved with his head.
All he needed to do was aim at a label, hit a button and a menu opened
inviting him to learn more about desks in general, about this desk, about the
history of the use of desks going back to the bench or “bank” on which
financial deals were carried out.
“Neat,” he said returning the
headset.
“It’s too pricy just now, but
soon I think this will become a museum standard, like the Greek columns out
front.”
“Very
important. Oversold a bit, I imagine, but very
important.”
“How oversold.”
“Well we really don’t have
any record of a wild population having gone extinct because of inbreeding. Local populations, there was a study of
butterflies in
“What about social insects,
bees and termites and ants. The queen
lays all the eggs.”
“Usually.”
“And the new queen mates only
with her brothers.”
“Obviously that isn’t
strictly true. There is some
mixing. Suppose two hives swarm at the
same time. What’s a male going to do? Say, ‘You aren’t my sister. Get away.’?”
“But why do they restrict
breeding to just the queen?”
“Conserves
resources. Also specialization is generally good. Those bees are all basically clones. They are genetically identical. So what is good for all is good for one. Think of them like cells in your body. Your cells divide, but they aren’t having sex
with each other. They leave that to
specialized cells in your gonads.”
“Well what about herding
animals, sheep or deer or walruses.
Again mating, at least for the males, is restricted. Isn’t that a waste of genetic diversity,
assuming it is always good?”
“You can throw in bower
birds, too if you like. The males build
their bowers and the females review them.
Then all the females mate with one male.
But there isn’t a scientist alive who can predict which one the females
will choose. And the females don’t seem
sure either at first. But once one of
them decides, the others fall into line.
In a way its like fall fashions.”
“And the
loss of diversity?”
“Well you have to balance
that against selecting for good genes. I
dare say it would be possible to pick out a few losers, ones who build lousy
bowers. They probably are unfit in other
ways, and eliminating them is good for the species. Ditto for herding animals.”
“But why not have all the fit
males mate; best of all possible worlds.”
“Maybe, but it really doesn’t
take that many males. With modern
techniques they can keep five bulls in the
“All right, then what about
reef animals, corals. They release their
gametes into the ocean. Does that mean
all corals of a species mate at random with every other coral polyp in the
world?”
“Actually, that has been
studied. And it turns out that a local
population is very close genetically and quite
distinct from others not that far away.”
“So it’s true. They are controlling their mating pool size
and limiting genetic diversity locally.”
“Doing both of those things,
yes. But whether the
purpose … sorry bad word. Whether
the effect of limiting gene pool size is beneficial, well nobody thinks
so. I expect that it’s a matter of range
for the gametes. A polyp releases a
gamete to go mate with a different polyp.
It doesn’t make much sense to give it, the gamete, enough energy to
travel eight thousand miles in the search.
It makes more sense, from a cost-benefit standpoint, to release a
thousand times as many that can travel eight miles. After all, the immediate vicinity is a lot more
likely to be a good place for a reef than a random spot, which will mostly be deep ocean, useless to a coral.”
“Of course. Everybody has
heard of lemmings. They don’t jump into
the sea, but their population surges and falls.
It’s been studied. Sometimes, as
with
“But the end result is to
reduce genetic diversity among voles.”
“Maybe, but it isn’t an
important effect. Otherwise all vole
populations would have the same cycle, but they don’t.”
“And why is there a greater
variety of trees in a tropical jungle than in a northern forest?”
“Good question. If you can answer it, it’ll get you a PhD in
botany. There is debate ongoing. What everyone agrees on is that the diversity
in the tropics is greater and that the forests are older. The northern forests have only regrown since the last ice age.”
“So evolution leads to greater
diversity.”
“That’s true in the large
sense. There is obviously more diversity
now than when evolution got started. But
whether in time those northern forests would develop the same diversity as the
tropics nobody knows.”
“But it could be that the
forests have evolved a lot of different species so that the effective gene pool
locally is smaller?”
“Well I’d phrase it
differently; there really isn’t any purpose in it. But to answer your
question, probably not. Nobody
expects a huge die off of northern forests because their effective gene pool
size was too big. The debate nowadays is
whether different species of trees in the tropics have evolved that exploit
subtle differences in the environment with different advantage. Personally I doubt that. The bulk of the species are widely
distributed and well mixed. It would be
a logger’s dream to run across a square mile with nothing but mahogany, but it
doesn’t happen. I think the main stream
now would probably say that the trees are all about the same and compete on an
equal footing, so they all have an equal chance and wind up mixed.”
Hapgood said, “Well we didn’t quite have him turning pale
with our questions, did we?”
They strolled
the esplanade. A marching band was
playing “The Stars and Stripes Forever.”
They visited the
"The common
element," said Jon, "Is freedom.
Jefferson wanted to secede from a kingdom. Lincoln was preventing secession from a
republic."
"That's how the world
sees it, but it won't wash. The question
is not the form of government. The
question is whether the government is supported by the people. There was no French Revolution in
England. Even the colonies never wanted
to topple the monarchy. They just wanted
out of it."
"I think it's time for
lunch."
There have been 2,075
visitors so far.