Biofilm simulation at the G.C. Marine Reserve

Last Friday, February 25th, the class read about a biofilm plate simulation. Ecologists studied communities of organisms to learn about species richness, species evenness, and the species diversity. The problem was to determine the distribution, abundance, and setting rates of benthic organisms. Our materials consisted of: graham crackers, frosting, sprinkles and other cake decorations, miniature marshmallows, lifesavers, small drink cups, plastic knives, a paper towel, and a picture-taking device. On our paper towel, which represents the ocean, we "glued" the graham cracker with cake icing. The graham cracker represented the plexiglas plate. Because plexiglas is smooth, the spat, larvae, and spores of many bottom dwelling organisms will not settle on it. We used the plastic knife to spread cake icing on top of the graham cracker to make the surface rough; not the young bottom dwellers can settle on the plexiglas. In order for the plexisglas to stay put, the ecologists had to bolt it down. We used Lifesavers gummies as our bolts. After we "bolted" our plexiglas, some organisms started to settle on the biofilm plate, or plexiglas. On the biofilm plate, red coralline algae, diatoms, barnacles, coral, and oysters began settling on the plate. The red sugar crystals represented the red corraline algae, brown long johns represented the diatoms, rainbow sprinkles represented the young barnacles and marshmallows represented the adult barnacles, rainbow long johns represented the coral, and blue or green dots represented the oysters. My biofilm plate contained 101 red corraline algae, 18 diatoms, 30 young barnacles and 3 adult barnacles, 34 coral, and 2 oysters. My biofilm plate (graham cracker) is compared to a quarter in both pictures.

                                                                         Before...

After...with adult barnacles