How is a spider like a cotton plant? How do we know, just from looking at the
shapes of its teeth, what an animal eats? Architects like to say "form follows
function," but that's backwards to a scientist. We say "function follows form."
Look carefully at any structure, at the right level of magnification, and how that
structure works - what it's good for - will be revealed.
When my mom went to college in the late 1950s, Biology 101 consisted mostly of
nature study, cataloguing and often drawing the adaptations of plants and animals
to the places they live, in terms of the shapes of their bodies - narrow leaves
conserve water, broad leaves capture more light, things like that. The Krebs cycle
was for premed students taking biochem. These days, even non-majors are
expected to memorize the basics of glucose metabolism and photosynthesis. Many
of them forget it after the exam, of course, but I think all this cellular fooforah has
had some good influence on a generation of Americans. They at least know that
molecules exist, and that molecules are the basis of all the drugs we take.
Unfortunately, I find that the current focus on memorizing molecular details means
that most students, and many SF writers, have missed the point. They don't seem
to understand at an intuitive level how biochemistry actually works, and this limits
their use of it to technobabble about genes and DNA (an exception is this Escape
Pod story, which also mentions functional groups from Organic I). The most basic
concept in biochemistry is shape. Every molecule is assembled out of atoms like
Lego bricks. The unique 3D shape of each assembly gives the resulting molecule
its particular function. Fibers are made of long molecules that cross-link to form
braided ropelike structures. It doesn't matter that cellulose is made from sugars by
plants, or that silk is made from proteins by insects, spiders, and transgenic goats.
The important part is the structure of long cross-linked chains (in the picture to the
right of that news release, the red and purple chains are bonded by yellow cross
links). The structure determines the properties.
Because they are too small to see directly, it helps to understand these things
through analogy and simulation. Compare the Thunderdriller, which my son built
from a Lego kit when he was about 8, to the enzyme "motor" that makes ATP
embedded in the inner membrane of the mitochondrion.
They are both pretty complex. There are gears that connect the wheels of the
Thunderdriller to the huge drill bit on the front, so that when a child (or a childlike
Ph.D.) rolls it across the floor, the forward motion of the wheels spins the drill bit.
I've never checked, since my son long ago cannibalized the parts for other
building projects, but I'll bet backwards motion would spin the drill bit in the
opposite direction. The same thing can happen with ATP synthase! This is just
one example of the much broader concept that function follows form. Most toxins,
most drugs, most disease organisms, have their effects through mimicking the
shape of some molecule produced inside the body. Imperfect mimics can have
interesting side effects, as they bind to their targets with a different strength than
the original, or bind to the wrong target, or even to more than one target.
In other words, most of a writer's social intuitions about deception and betrayal
apply to some extent even at the cellular level!
Nothing is free, of course. The increasing sophistication of college students and
writers about cells and molecules means that they spend much less time studying
ecology and natural history. Worse, they believe that these subjects have nothing
to do with one another! I was reminded how common this problem is during a trip
to Glacier National Park this summer. We went on several ranger-led hikes, one
of them with a geologist named Tegan, who I can only assume was named for the
Dr. Who companion. She was a total Time Lord, brilliant at pointing out the
connections between "different" fields of science, which is rare. Most of what the
Ranger said seemed new to the people on the hike, including me, who made it
through a biology major without ever taking a geology class.
At the very beginning of our trek up to Avalanche Lake, Ranger Tegan showed us
a billion-year-old stromatolite (looking sort of like a brain coral, but built by
bacteria). She used the 1989 Loma Prieta earthquake, which flattened her
hometown of Santa Cruz, to dramatize the slow collision of the tectonic plates that
broke the earth's crust and raised those buried relics up to where we can see them.
She asked our tour group to read the story of an avalanche, which had stripped the
side of the valley where it started almost to bare rock; at the bottom of the valley it
had snapped trees off at the level of the standing snowfall (about 20 feet!); and on
the opposite side of the valley, the pressure of the air being pushed by the falling
wall of snow had been enough to knock trees over uphill, like pictures you may
have seen of an atomic blast, or the Tunguska explosion. By looking at the
structure of the scene in front of us, we could determine what had happened.
It was quite a morning, overall, even before she saved us from the bear.
Not with a gun - not even with bear spray (molecule, molecule, molecule!). She
just applied principles of animal behavior. We made enough noise to let the bear
know where we were, that there were a lot of us, and that we weren't going to start
any trouble. See, animals, especially predators, are not stupid. They are not
mindless video game sprites, charging anything that enters their aggro radius.
Most importantly, they don't stand next to you and trade shots until someone's
health bar runs out. This is from a book of Theodore Roosevelt's bear-hunting
essays, which I found on the shelf at my in-laws' home in Montana on that same
trip:
"A bear is apt to rely mainly on his teeth or claws according to whether his
efforts are directed primarily towards killing his foe or to making good his
own escape. In the latter event he trusts chiefly to his claws . . . In such a
case he usually strikes a single blow and gallops on without halting, though
that one blow may have taken life. If the claws are long and sharp (as in
early spring, or even in the fall, if the animal has been working over soft
ground) they add immensely to the effect of the blow, for they cut like blunt
axes . . . If a bear means mischief and charges not to escape but to do
damage, its aim is to grapple with or throw down his foe and bite him to
death."
This is a whole other level of detail and realism (but still, function follows form).
I've often heard SF writers say that they write dystopias because conflict drives
the story. Ironically, I've equally often heard writers say that they hate writing
combat, because it's so boring, because all combats are the same. Those writers
could seek inspiration from other fields of literature, like natural history.
The same basic principles unite all of science, despite the politics of professional
and educational "disciplines." SF is a prime place to show that integration.
Randall Hayes also organizes the Greensboro Science Cafe series and runs his
own education company, Agnosia Media, LLC. In between columns, keep up the
discussion on PlotBot's new Facebook page.