An emoticon, sometimes called a smiley, is a face made from punctuation marks and other special characters on your computer keyboard. Emoticons are meant to show an emotion. Let's say you want to show that you are happy or smiling. You can do this by using a : (colon) and a ) (right parenthesis) to make : ) . This is an example of an emoticon. The cool thing is you're free to use any of the characters on your keyboard.

It's all up to your imagination ; )

But another way to construct an emoticon that even your imagination might not think of is with our Emoticonstructor computer. Please read on before you try it out!

Actually, the Emoticonstructor is about as ancient and dumb as a computer can be. Its memory banks hold only a bunch of punctuation marks and three simple rules.

1. Arrange randomly selected punctuation marks on a circle, putting two marks in the top half and one in the bottom half.

2. Save any particular arrangement that the computer operator selects.

3. Mix the top and bottom parts of selected arrangements to make new arrangements.

With only these elements and these rules, Emoticonstructor, with you as tester, will "evolve" a FACE that expresses a human emotion of your choosing!

The Emoticonstructor uses the same process that nature uses in making successful "designs" for living plants and animals.

If people designed animals, they might all look very much like people. Just picture all the aliens you have seen in science fiction movies! They might have green skin, scales, tails, and be covered in slime, but they often still have the basic design features of humans--two legs, two arms, one head with a standard face, walk upright, and so on. They usually even speak our language!

Instead, nature "designs" animals based on what works in the animal's particular environment. So what we get is a huge variety of animal "designs" that humans would never have thought of.

The Emoticonstructor shows how this same process could work inside a computer. In nature, how well the animal and its offspring survive in their particular environment is the "test" for a successful design. With the Emoticonstructor, how well you think an emoticon (or face) shows a particular emotion is the test for success.

Now NASA scientists are experimenting with "artificial evolution," using computers to "evolve" designs for special equipment that will meet very special needs. For example, NASA engineers wanted to design an antenna to fly in three very small satellites in the Space Technology 5 mission. The antenna on any spacecraft is very important, because it lets the spacecraft send information about its spacey surroundings and its own state of health back to Earth. The antenna also allows a spacecraft to receive instructions from Earth. NASA wanted the best and smallest possible antennas for these tiny spacecraft. So they gave the design job to a computer--or actually 35 computers all working together.

Tiny antenna designed for Space Technology 5 spacecraft using artificial evolution.

Each of three Space Technology 5 spacecraft had a tiny antenna. In this painting, a small wire is shown in the antenna's place.

To start, the engineers gave the computers a list of the jobs the antenna needed to be able to do. The computers then ran a program that created millions of imaginary antennas inside the computer by playing with the lengths and widths of wires and how the wires would be bent and branched. Then the program tested each design to see how well it worked. The best working designs were mixed up and used to create another batch of designs. Those were again tested inside the computer. The best ones of those were again used to become the "parents" of the next generation.

In this way, each generation of antennas got a little better at doing exactly the jobs needed, until finally no better antenna could be created by the computer. The computer's final design was so strange looking that no human would have thought of it. The engineers used a printout of the antenna design to build it out of wire, and then they tested it in a special chamber. It worked!

While natural evolution usually takes place over a long time and many generations, artificial evolution using many powerful computers can create and test hundreds or thousands of generations in a matter of hours or days.

Who knows where the technology of artificial evolution will lead? But, if nothing else, it gets human to think of ways to do things that they might never have dreamed of left to their own designs!