"We tried to mimic some classic video games," he said. For example, one game in which players guide paramecia to "gobble up" little balls, a la PacMan, was christened PAC-mecium. Then there is Biotic Pinball, POND PONG and Ciliaball. The latter game is named for the tiny hairs, called cilia, that paramecia use in a flipper-like fashion to swim around -- and in the game enables kicking a virtual soccer ball.
The basic design of the games involving paramecia -- the single-celled organisms used in countless biology experiments from grade school classes to university research labs -- consists of a small fluid chamber within which the paramecia can roam freely. A camera sends live images to a video screen, with the "game board" superimposed on the image of the paramecia. A microprocessor tracks the movements of the paramecia and keeps score.
The player attempts to control the paramecia using a controller that is much like a typical video game controller. In some games, such as PAC-mecium, the player controls the polarity of a mild electrical field applied across the fluid chamber, which influences the direction the paramecia move. In Biotic Pinball, the player injects occasional whiffs of a chemical into the fluid, causing the paramecia to swim one direction or another.