by Helen E. Davis

This article first appeared in Tightbeam 169, in May, 1991

Building a Martian is easy. You start with a piece of paper and some pencils or crayons. Draw a weird body with two or more legs beneath it, a weird head on top, an assortment of features attached in various places, and a wide, toothy grin. Add a few red rocks in the background, and viola! You have a Martian.

But -- what if you should like something a little more challenging and much stranger than you might think up on your own? What if you would like to build a better Martian? With the help of a Random Number Generator (RNG) and a few practical laws of biology, it's easy to do. And it can get just as complicated as you want.

For a simple example, I will start with a set of RNG-created letters. (A RNG is a device which picks numbers randomly. My favorite is a ten-sided die, but you can also write a computer program to do the same thing.

Now -- how do we combine these numbers into something workable? We could draw a blob with the various features sticking out at random, but that would violate the biological laws of symmetry, cephalization, and aesthetic good taste. (So does a slime mold -- but that's definately not a higher organism!) Let's take a look at the numbers and see what jumps out at us.

The weight is exceedingly light for the height, so we are obviously not dealing with something short and squat. Perhaps it is very, very thin, something like a stalk -- but wouldn't that have a great tendency to fall over? Or maybe it just has very long antennae and limbs coming out of a dense, round body. I like that, so I'll keep it.

Three eyes and three antennae; that suggests a correlation. Perhaps the eyes are mounted on top of the antennae, and thus could be raised up high to search for enemies or food. If our Martian is bilaterally symmetrical (having two sides which mirror each other) then the antennae could be arranged across the top of body, with one toward each side and one in the middle.

Five limbs and five mouths; again a correlation. The mouths could be located at the base of the limbs, and it could feed by picking up things with its two fingers and putting them into the closest mouth. But how does one fit five limbs into a bilaterally symmetrical system? If we switch to radial symmetry (all structures radiate from a central point) our Martian will began to resemble a starfish. The antennae can be rearranged into a triangular pattern, in order to fit with the radial symmetry.

Never be afraid to readjust established features in order to fit them into a new pattern.

And then there are the nine brains. Nine? Why would the Martian need so many brains? The law of cephalization rules that there should be only one center of for the processing of information and decision making, so we shall make one the major brain and the rest into glorified ganglia. These minor brains can be responsible for reflexes and fine motor movement. And since the eight minor brains correlate with the number of limbs and antennae, we can locate one at the base of each appendage. The ninth and major brain would be centered in the body, close to the stomach and sheltered beneath a layer of bone or chitin. Scales? Sounds good. They could give it protection from any natural predators.

Have we accounted for all the senses? Ears might be placed alongside the eyes, the better to detect the environment, and there should be some chemical receptors as well. More chemical receptors would be found at the ends of the limbs, perhaps between the toes, to help it find edible food.

And sex -- uhm, mumble, mumble, mumble. It's done in private, so we don't know anything about it. (Actually, sex and genders can be a very complicated, very interesting area in itself.)

Now, let's see about making it a Martian -- that is, how shall we adapt it to life on Mars? Some facts about the planet are:

How can a life form exist without oxygen, water, or air pressure? Even if it does have nine brains?

Oxygen is not required for life, actually. Many bacteria live anerobically (without oxygen). Furthermore, oxygen is only a potential requirement if we assume that Martians have the same biochemical properties as Terrans, and there's no need for that. In fact, there is proof that Martians do not have the same biochemisrty as Terrans, since their plants reflect the red wavelength which ours depend upon, and absord the blue and green which ours throw away. That, of course, is why Mars looks so red.

Water is a more difficult problem. There is the theory that life started as a series of chemical reactions in water, and the cell evolved as a way of keeping the chemicals from floating out of reach of one another. Water is still important because it holds the chemicals close enough together to make reactions take place. Still reactions will take place in air, albeit at a slower rate. Here on Earth, water reactions out-compete air reactions, but perhaps on a planet that has no water air reactions could evolve into complex lifeforms. (Okay, okay, Mars had water in its past -- but it all disappeared before life arose. Just as we are made mostly of water, the Martians must be filled with air. Therefore, their bodies are alot larger and bulkier than we thougt.

But in the low air pressure of Mars, the molecules would be prohibitively far apart. Life might have started deep underground, in pressurized caves, and only after cell walls evolved could come out on the surface. Still, the Martians would think and move with agonizing slowness -- which gives us a reason for all those brains.

More questions could be asked: How does the digestive system work? How should we adapt them to make them intelligent? What kind of society do the intelligent Martians have? Buildings? Chairs? But each set of questions leads to more complicated, more interesting questions and puzzles to solve.

A little more fun than just drawing blobs, isn't it?

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