(c) Josep M. Llort Planchadell 1994.

Simulation of the evolution of a bacterian population, recommended for High School and College. First version of this program was awarded by the Spanish Ministry of Education and Science in the international Contest of educative software, year 1992. Second version, in catalan, was edited by the PIE, an organism of the Catalonia Government, year 1994. Although it is an old program, in MSDOS, is easy to use it because it has an interface very similar to Windows, with pull-down menus, buttons, context sensitive help and interaction with keyboard and mouse.

In the window of bacterial strains, the existing varieties in the population are seen, with their number of bacteria and their chromosome, indicating the state of their genes by means of a color code (gray: inactive; brown: assets; green: positive taxis, etc).

General aspect of Evolució Bacteriana, with the three main windows of the program.

Environment window, at right, shows the value of the main environmental factors on which the survival of the bacteria depends.

General information window, underneath, indicates the number of cycles that simulation is working, the number of bacterial strains, the total amount of bacteria and whichever varieties have been recorded in the fossil registry of the program.

New strains appear by random mutations or conjugation. When some of these phenomena takes place, messages appear informing about it. User can choose what types of messages are shown.

Message informing a M0 strain bacterium has mutated, producing a new strain: M25A.

Window to modify the amount of penicillin in the environment

Bacteria live in an artificial environment that can be modified, including different nutrients, ultraviolet radiation and diverse antibiotics.

Interaction of bacteria with this environment is realised based on its genetic characteristics, so that better adapted strains multiply and the worse one adapted are reduced and disappear. This evolution is observed in the bacterial strains window:

Bacterial strains best adapted to the environment will be the most abundant.

At any time, we can see a graphical representation of bacterial population in function of time and to relate it to different environmental factors.

Diminution of bacterial population after introducing penicillin.

More significant bacterial strains of a simulation are registered in the program, that allows to see from what strain has been originated, by mutation (m) or conjugation (r).

Genealogical tree of main bacterial strains of a simulation.

Evolució Bacteriana 2.0. is written in Catalan, but it is possible to use it without knowing this language, specially if you know Italian, French, Spanish or another Latin language.

The program's help system has more information, including a teacher's guide.

It is important to know that the program was made with Turbo Pascal 7.0. for MS-DOS. It also runs under Windows 95, but with Windows 98 or later does not work (it produces a run-time error). Luckyly, it is possible to be executed using the program DosBox (among others emulators), that must be installed in the following way:

1. Download the Evolució Bacteriana install program . Decompress it with Winrar and execute it, installing the program in a folder with accessible name from MSDOS (names of 8 characters at the most, without spaces nor accents; for example: evobac2).

2. Download DosBox for Windows and install it.

Every time we want execute Evolució Bacteriana, we must:

1. Execute DosBox.

2. In the DosBox window, write the following (every line must be finished by press the "Intro" key. The symbol "/" is equivalent to "\"):

3. Evolució Bacteriana will start in the DosBox window.

4. When finished, enter the command "exit" to close the DosBox window.